- Infectious Disease
Professor - Med Center Line, Medicine - Infectious Diseases
Member, Medical School Faculty Senate (1999 - 2002)
Co-Chairman, Administrative Panel on Biosafety (1995 - 2015)
Honors & Awards
Fellow, Infectious Disease Society of America (2005)
Divisional Award for Exceptional Contributions in Education in the Division of Infectious Disease, Department of Medicine (2004)
Infectious Diseases Teaching Award, Division of Infectious Diseases (2004)
HIV Program Clinical Excellence Award, Department of Veterans Affairs (2001)
Infectious Diseases Teaching Award, Division of Infectious Diseases (1997)
Fellow, American College of Physicians (1996)
Boards, Advisory Committees, Professional Organizations
Editor-in-Chief, Diagnostic Microbiology and Infectious Disease (2013 - Present)
Residency:Good Samaritan Regional Medical Center (1988) AZ
Fellowship:Stanford University School of Medicine (1990) CA
Board Certification: Infectious Disease, American Board of Internal Medicine (1990)
Board Certification: Internal Medicine, American Board of Internal Medicine (1988)
Internship:Good Samaritan Regional Medical Center (1986) AZ
Medical Education:Northwestern Memorial Hospital (1985) IL
BS, Seattle University, Biology (1980)
---, Stanford University, Infectious Diseases Fellowship (1990)
Community and International Work
Tri-national OPTIMA Trial
HIV Clinical Trial
UK MRC, Canadian CIHR
Opportunities for Student Involvement
Merigan TC, Katzenstein DA, Holodniy M. "United States Patent 5,968,730 HIV PCR Directs Drug Use", Leland Stanford Junior University
Merigan TC, Katzenstein DA, Holodniy M. "United States Patent 6,503,705 Polymerase Chain Reactions for Monitoring Antiretroviral Therapy and Making Therapeutic Decisions in the Treatment of Acquired Immunodeficiency Syndrome", Leland Stanford Junior University
Merigan TC, Katzenstein DA, Holodniy M. "United States Patent 7,129,041 Polymerase chain reaction assays for monitoring antiviral therapy and making therapeutic decisions in the treatment of acquired immunodeficiency syndrome", Leland Stanford Junior University
Current Research and Scholarly Interests
My research program is currently focused in three areas: 1) translational research (HCV/HIV viral evolution and antiviral resistance prevalence and development), 2) HIV/HCV clinical trials (diagnostic assay/medical device, antiretrovirals, ARVs and immunomodulators), and 3) health services research focusing on cost effectiveness of HIV antibody and ARV resistance testing and ARV utilization and clincal outcome.
Acute and chronic immune biomarker changes during interferon/ribavirin treatment in HIV/HCV co-infected patients
JOURNAL OF VIRAL HEPATITIS
2015; 22 (1): 25-36
Chronic viral infections lead to persistent immune activation, which is alleviated by eradicating or suppressing the infection. To understand the effects of interferon treatment on immune system activation by chronic infections, we evaluated kinetic patterns of a broad spectrum of serum biomarkers during HCV treatment in HIV/HCV co-infected patients. HCV viral load and 50 biomarkers were analysed at baseline and 27 time points during pegylated interferon-alpha and ribavirin (IFN/RBV) treatment of 12 HIV/HCV co-infected patients. We evaluated biomarker changes from baseline for each time point and biomarker correlations with clinical parameters, treatment response and liver histopathology. IL-1α, IL-12p40, IL-1RA, IP-10, MIG, MIP-1α/1β, HGF, sCD40L, TRAIL and leptin increased in the first day. IL-12p70, IL-17A, IL-10, GROα, IL-8, MCP-3, IL-4 and M-CSF peaked later during week 1. IL-1α, HGF, IP-10, MIP-1α, TRAIL, sCD40L, IL-10, IL-12p70, MCP-3, FGFb, ENA-78, TGF-β, IL-2, IFN-γ, IL-6, IL-15, IL-7 and PDGF-BB decreased below baseline over the course of treatment. Higher BMI, baseline HCV viral load and leptin levels were associated with lack of sustained virologic response. ENA-78 was associated with sustained viral response. Positive correlations were found between liver inflammation and baseline CD4 count, sVCAM and HGF; fibrosis stage and HGF; liver steatosis, BMI and leptin. Our findings suggest IFN/RBV treatment initially increases levels of several biomarkers, but eventually leads to a decline in many immune markers. These findings shed light on the relationship between IFN treatment and immune activation by chronic viral infections, such as HCV.
View details for DOI 10.1111/jvh.12226
View details for Web of Science ID 000346826600005
View details for PubMedID 24506344
Incidence of Medically-Attended Norovirus-Associated Acute Gastroenteritis in Four Veteran's Affairs Medical Center Populations in the United States, 2011-2012.
2015; 10 (5): e0126733
An estimated 179 million acute gastroenteritis (AGE) illnesses occur annually in the United States. The role of noroviruses in hospital-related AGE has not been well-documented in the U. S. We estimated the population incidence of community- acquired outpatient and inpatient norovirus AGE encounters, as well as hospital-acquired inpatient norovirus AGE among inpatients at four Veterans Affairs (VA) Medical Centers (VAMCs). Fifty (4%) of 1,160 stool specimens collected ≤7 days from symptom onset tested positive for norovirus. During a one year period, the estimated incidence of outpatient, community- and hospital-acquired inpatient norovirus AGE was 188 cases, 11 cases, and 54 cases/ 100,000 patients, respectively. This study demonstrates the incidence of outpatient and community- and hospital-acquired inpatient norovirus AGE among the VA population seeking care at these four VAMCs.
View details for DOI 10.1371/journal.pone.0126733
View details for PubMedID 25996826
Risk of Cardiovascular Events Associated With Current Exposure to HIV Antiretroviral Therapies in a US Veteran Population.
Clinical infectious diseases : an official publication of the Infectious Diseases Society of America
To characterize the association of antiretroviral drug combinations on risk of cardiovascular events. Certain antiretroviral medications for human immunodeficiency virus (HIV) have been implicated in increasing risk of cardiovascular disease. However, antiretroviral drugs are typically prescribed in combination. We characterized the association of current exposure to antiretroviral drug combinations on risk of cardiovascular events including myocardial infarction, stroke, percutaneous coronary intervention, and coronary artery bypass surgery. We used the Veterans Health Administration Clinical Case Registry to analyze data from 24 510 patients infected with HIV from January 1996 through December 2009. We assessed the association of current exposure to 15 antiretroviral drugs and 23 prespecified combinations of agents on the risk of cardiovascular event by using marginal structural models and Cox models extended to accommodate time-dependent variables. Over 164 059 person-years of follow-up, 934 patients had a cardiovascular event. Current exposure to abacavir, efavirenz, lamivudine, and zidovudine was significantly associated with increased risk of cardiovascular event, with odds ratios ranging from 1.40 to 1.53. Five combinations were significantly associated with increased risk of cardiovascular event, all of which involved lamivudine. One of these-efavirenz, lamivudine, and zidovudine-was the second most commonly used combination and was associated with a risk of cardiovascular event that is 1.60 times that of patients not currently exposed to the combination (odds ratio = 1.60, 95% confidence interval, 1.25-2.04). In the VA cohort, exposure to both individual drugs and drug combinations was associated with modestly increased risk of a cardiovascular event.
View details for DOI 10.1093/cid/civ316
View details for PubMedID 25908684
- Sofosbuvir-Based Treatment Regimens for Chronic, Genotype 1 Hepatitis C Virus Infection in US Incarcerated Populations A Cost-Effectiveness Analysis ANNALS OF INTERNAL MEDICINE 2014; 161 (8): 546-U43
Effect of Management Strategies and Clinical Status on Costs of Care for Advanced HIV
AMERICAN JOURNAL OF MANAGED CARE
2014; 20 (5): E129-E137
View details for Web of Science ID 000339146800002
Application of a non-amplification-based technology to detect invasive fungal pathogens
DIAGNOSTIC MICROBIOLOGY AND INFECTIOUS DISEASE
2014; 78 (2): 137-140
Current diagnostic techniques for fungal diseases could be improved with respect to sensitivity, specificity, and timeliness. To address this clinical need, we adapted a non-amplification-based nucleic acid detection technology to identify fungal pathogens. We demonstrate a high-specificity, detection sensitivity, reproducibility, and multiplex capacity for detecting fungal strains.
View details for DOI 10.1016/j.diagmicrobio.2013.11.013
View details for Web of Science ID 000330149700007
Public Health Practice Is Not Research.
American journal of public health
Scientific and clinical activities undertaken by public health agencies may be misconstrued as medical research. Most discussions of regulatory and legal oversight of medical research focus on activities involving either patients in clinical practice or volunteers in clinical trials. These discussions often exclude similar activities that constitute or support core functions of public health practice. As a result, public health agencies and practitioners may be held to inappropriate regulatory standards regarding research. Through the lens of the Departments of Defense and Veterans Affairs, and using several case studies from these departments, we offer a framework for the adjudication of activities common to research and public health practice that could assist public health practitioners, research oversight authorities, and scientific journals in determining whether such activities require regulatory review and approval as research. (Am J Public Health. Published online ahead of print February 13, 2014: e1-e7. doi:10.2105/AJPH.2013.301663).
View details for DOI 10.2105/AJPH.2013.301663
View details for PubMedID 24524499
MicroRNA and hepatitis C virus- challenges in investigation and translation: a review of the literature.
Diagnostic microbiology and infectious disease
Investigations into the role of microRNA (miRNA) in hepatitis C virus (HCV) infection, disease pathogenesis and host immune and treatment response have potential to produce innovations in diagnosis, prognosis and therapy. However, investigational challenges remain in generating clinically useful and reproducible results. We review the literature with a primary emphasis on methods and technologies used to construct our current understanding of miRNA and HCV disease. A second emphasis is to understand potential clinical research applications and provide clarification of previous study results. Many miRNA have key roles in viral and immunopathogenesis of HCV infection across multiple tissue compartments. Controversy exists among published studies regarding relative measurements, temporal changes and biological significance of specific miRNA and HCV infection. To reconcile diverging data, additional research into optimal sample processing, in vitro models, techniques for microarray differential expression of miRNAs, practices for sample result normalization, and effect of HCV genotype variation on expression are all necessary. Microarray and miRNA isolation techniques should be selected based on ability to generate reproducible results in the sample type of interest. More direct comparisons of efficacy and reliability of various multiplex microarrays and an improved consensus around miRNA normalization and quantitation are necessary so that data can be compared across studies.
View details for DOI 10.1016/j.diagmicrobio.2014.05.024
View details for PubMedID 24996839
The VACS Index Accurately Predicts Mortality and Treatment Response among Multi-Drug Resistant HIV Infected Patients Participating in the Options in Management with Antiretrovirals (OPTIMA) Study.
2014; 9 (3): e92606
The VACS Index is highly predictive of all-cause mortality among HIV infected individuals within the first few years of combination antiretroviral therapy (cART). However, its accuracy among highly treatment experienced individuals and its responsiveness to treatment interventions have yet to be evaluated. We compared the accuracy and responsiveness of the VACS Index with a Restricted Index of age and traditional HIV biomarkers among patients enrolled in the OPTIMA study.Using data from 324/339 (96%) patients in OPTIMA, we evaluated associations between indices and mortality using Kaplan-Meier estimates, proportional hazards models, Harrel's C-statistic and net reclassification improvement (NRI). We also determined the association between study interventions and risk scores over time, and change in score and mortality.Both the Restricted Index (c = 0.70) and VACS Index (c = 0.74) predicted mortality from baseline, but discrimination was improved with the VACS Index (NRI = 23%). Change in score from baseline to 48 weeks was more strongly associated with survival for the VACS Index than the Restricted Index with respective hazard ratios of 0.26 (95% CI 0.14-0.49) and 0.39(95% CI 0.22-0.70) among the 25% most improved scores, and 2.08 (95% CI 1.27-3.38) and 1.51 (95%CI 0.90-2.53) for the 25% least improved scores.The VACS Index predicts all-cause mortality more accurately among multi-drug resistant, treatment experienced individuals and is more responsive to changes in risk associated with treatment intervention than an index restricted to age and HIV biomarkers. The VACS Index holds promise as an intermediate outcome for intervention research.
View details for DOI 10.1371/journal.pone.0092606
View details for PubMedID 24667813
Human Pegivirus (HPgV or GB virus C) RNA is found in multiple blood mononuclear cells in vivo and serum-derived viral RNA containing particles are infectious in vitro.
The Journal of general virology
Human Pegivirus (HPgV; previously called GB virus C/hepatitis G virus) has limited pathogenicity despite causing persistent infection, and is associated with prolonged survival in HIV-infected individuals. Although HPgV RNA is found in and produced by T and B lymphocytes, the primary permissive cell type(s) are unknown. We quantified HPgV RNA in highly purified CD4+ and CD8+ T cells, including naïve, central memory, and effector memory populations, and in B cells (CD19+), NK cells (CD56+) cells and monocytes (CD14+) using real time RT-PCR. Single genome sequencing was performed on virus within individual cell types to estimate genetic diversity among cell populations. HPgV RNA was present in CD4+ and CD8+ T lymphocytes (9 of 9 subjects), B lymphocytes (7 of 10), NK cells and monocytes (both 4 of 5). HPgV RNA levels were higher in naïve (CD45RA+) CD4+ cells than in central memory and effector memory cells (p<0.01). HPgV sequences were highly conserved between patients (0.117 ± 0.02 substitutions per site; range 0.58-0.14) and within subjects (0.006 ± 0.003 substitutions per site; range 0.006-0.010). The non-synonymous/synonymous substitution ratio was 0.07 suggesting low selective pressure. CFSE-labeled HPgV RNA-containing particles precipitated by a commercial exosome isolation reagent delivered CSFE to uninfected monocytes, NK cells, T and B lymphocytes, and HPgV RNA was transferred to peripheral blood mononuclear cells with evidence of subsequent viral replication. Thus, HPgV RNA-containing serum particles including microvesicles may contribute to delivery of HPgV to PBMCs in vivo, explaining the apparent broad tropism of this persistent human RNA virus.
View details for DOI 10.1099/vir.0.063016-0
View details for PubMedID 24668525
Cost-Effectiveness of Newer Antiretroviral Drugs in Treatment-Experienced Patients With Multidrug-Resistant HIV Disease.
Journal of acquired immune deficiency syndromes
2013; 64 (4): 382-391
Newer antiretroviral drugs provide substantial benefits but are expensive. The cost-effectiveness of using antiretroviral drugs in combination for patients with multidrug-resistant HIV disease was determined.A cohort state-transition model was built representing treatment-experienced patients with low CD4 counts, high viral load levels, and multidrug-resistant virus. The effectiveness of newer drugs (those approved in 2005 or later) was estimated from published randomized trials. Other parameters were estimated from a randomized trial and from the literature. The model had a lifetime time horizon and used the perspective of an ideal insurer in the United States. The interventions were combination antiretroviral therapy, consisting of 2 newer drugs and 1 conventional drug, compared with 3 conventional drugs. Outcome measures were life-years, quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness.Substituting newer antiretroviral drugs increased expected survival by 3.9 years in advanced HIV disease. The incremental cost-effectiveness ratio of newer, compared with conventional, antiretroviral drugs was $75,556/QALY gained. Sensitivity analyses showed that substituting only one newer antiretroviral drug cost $54,559 to $68,732/QALY, depending on assumptions about efficacy. Substituting 3 newer drugs cost $105,956 to $117,477/QALY. Cost-effectiveness ratios were higher if conventional drugs were not discontinued.In treatment-experienced patients with advanced HIV disease, use of newer antiretroviral agents can be cost-effective, given a cost-effectiveness threshold in the range of $50,000 to $75,000 per QALY gained. Newer antiretroviral agents should be used in carefully selected patients for whom less expensive options are clearly inferior.
View details for DOI 10.1097/QAI.0000000000000002
View details for PubMedID 24129369
Safety of Zoster Vaccine in Elderly Adults Following Documented Herpes Zoster
JOURNAL OF INFECTIOUS DISEASES
2013; 208 (4): 559-563
Background. After completion of the Shingles Prevention Study (SPS; Department of Veterans Affairs Cooperative Studies Program Number 403), SPS participants who had initially received placebo were offered investigational zoster vaccine without charge. This provided an opportunity to determine the relative safety of zoster vaccine in older adults following documented herpes zoster (HZ).Methods. A total of 13 681 SPS placebo recipients who elected to receive zoster vaccine were followed for serious adverse events (SAE) for 28 days after vaccination. In contrast to the SPS, a prior episode of HZ was not a contraindication to receiving zoster vaccine. The SPS placebo recipients who received zoster vaccine included 420 who had developed documented HZ during the SPS.Results. The mean interval between the onset of HZ and the receipt of zoster vaccine in the 420 recipients with prior HZ was 3.61 years (median interval, 3.77 years [range, 3-85 months]); the interval was <5 years for approximately 80% of recipients. The proportion of vaccinated SPS placebo recipients with prior HZ who developed ≥1 SAE (0.95%) was not significantly different from that of vaccinated SPS placebo recipients with no prior history of HZ (0.66%), and the distribution of SAEs in the 2 groups was comparable.Conclusions. These results demonstrate that the general safety of zoster vaccine in older persons is not altered by a recent history of documented HZ, supporting the safety aspect of the Centers for Disease Control and Prevention Advisory Committee on Immunization Practices recommendation to administer zoster vaccine to all persons ≥60 years of age with no contraindications, regardless of a prior history of HZ.
View details for DOI 10.1093/infdis/jit182
View details for Web of Science ID 000322412100005
View details for PubMedID 23633406
Concurrent outbreaks with co-infection of norovirus and Clostridium difficile in a long-term-care facility
EPIDEMIOLOGY AND INFECTION
2013; 141 (8): 1598-1603
SUMMARY We describe an outbreak of simultaneous Clostridium difficile and norovirus infections in a long-term-care facility. Thirty patients experienced acute gastroenteritis, and four had co-infection with identical C. difficile 027 and genotype II.4 New Orleans norovirus strains. Co-occurring infection requires improved understanding of risk factors, clinical impact, and testing strategies.
View details for DOI 10.1017/S0950268813000241
View details for Web of Science ID 000321763100004
View details for PubMedID 23433360
Health-related Quality of Life Assessment after Antiretroviral Therapy: A Review of the Literature.
2013; 73 (7): 651-672
Antiretroviral (ARV) treatment for HIV infection has resulted in significant improvement in immunologic and virologic parameters, as well as a reduction in AIDS-defining illnesses and death. Over 25 medications are approved for use, usually in combination regimens of three or four ARVs. Several ARVs are now available as combinatorial products, which have been associated with better adherence. However, while ARV therapy has prolonged life, ARVs also pose a challenge for quality of life as they can cause significant side effects in addition to the potential for drug toxicity and interaction. Given the many complications, side effects and symptoms of HIV/AIDS in addition to associated medical and psychiatric co-morbidities, the need to understand and assess how these interactions may affect health-related quality of life (HRQOL) has grown. Numerous instruments (some validated, others not) are available and have been applied to understanding how ARV treatment affects HRQOL in those with HIV infection, both in clinical trials and clinical practice. In general, ARV treatment improves HRQOL, but this is dependent on the population being studied, the HRQOL instrument being used and the timeframe during which HRQOL has been studied. This article provides a review of the literature on quality of-life assessment as it relates to ARV treatment in developed countries and briefly reviews the HRQOL instruments used, how they have been applied to ARV utilization, and where future research should be applied in HRQOL assessment and HIV infection.
View details for DOI 10.1007/s40265-013-0040-4
View details for PubMedID 23591907
- Immune Biomarker Differences and Changes Comparing HCV Mono-Infected, HIV/HCV Co-Infected, and HCV Spontaneously Cleared Patients PLOS ONE 2013; 8 (4)
- Risk of Cardiovascular Disease from Antiretroviral Therapy for HIV: A Systematic Review PLOS ONE 2013; 8 (3)
Cost-Effectiveness Analysis of Risk-Factor Guided and Birth-Cohort Screening for Chronic Hepatitis C Infection in the United States
2013; 8 (3)
No consensus exists on screening to detect the estimated 2 million Americans unaware of their chronic hepatitis C infections. Advisory groups differ, recommending birth-cohort screening for baby boomers, screening only high-risk individuals, or no screening. We assessed one-time risk assessment and screening to identify previously undiagnosed 40-74 year-olds given newly available hepatitis C treatments.A Markov model evaluated alternative risk-factor guided and birth-cohort screening and treatment strategies. Risk factors included drug use history, blood transfusion before 1992, and multiple sexual partners. Analyses of the National Health and Nutrition Examination Survey provided sex-, race-, age-, and risk-factor-specific hepatitis C prevalence and mortality rates. Nine strategies combined screening (no screening, risk-factor guided screening, or birth-cohort screening) and treatment (standard therapy-peginterferon alfa and ribavirin, Interleukin-28B-guided (IL28B) triple-therapy-standard therapy plus a protease inhibitor, or universal triple therapy). Response-guided treatment depended on HCV genotype. Outcomes include discounted lifetime costs (2010 dollars) and quality adjusted life-years (QALYs). Compared to no screening, risk-factor guided and birth-cohort screening for 50 year-olds gained 0.7 to 3.5 quality adjusted life-days and cost $168 to $568 per person. Birth-cohort screening provided more benefit per dollar than risk-factor guided screening and cost $65,749 per QALY if followed by universal triple therapy compared to screening followed by IL28B-guided triple therapy. If only 10% of screen-detected, eligible patients initiate treatment at each opportunity, birth-cohort screening with universal triple therapy costs $241,100 per QALY. Assuming treatment with triple therapy, screening all individuals aged 40-64 years costs less than $100,000 per QALY.The cost-effectiveness of one-time birth-cohort hepatitis C screening for 40-64 year olds is comparable to other screening programs, provided that the healthcare system has sufficient capacity to deliver prompt treatment and appropriate follow-on care to many newly screen-detected individuals.
View details for DOI 10.1371/journal.pone.0058975
View details for Web of Science ID 000316549400032
View details for PubMedID 23533595
Dengue Surveillance in Veterans Affairs Healthcare Facilities, 2007-2010
PLOS NEGLECTED TROPICAL DISEASES
2013; 7 (3)
Although dengue is endemic in Puerto Rico (PR), 2007 and 2010 were recognized as epidemic years. In the continental United States (US), outside of the Texas-Mexico border, there had not been a dengue outbreak since 1946 until dengue re-emerged in Key West, Florida (FL), in 2009-2010. The objective of this study was to use electronic and manual surveillance systems to identify dengue cases in Veterans Affairs (VA) healthcare facilities and then to clinically compare dengue cases in Veterans presenting for care in PR and in FL.Outpatient encounters from 1/2007-12/2010 and inpatient admissions (only available from 10/2009-12/2010) with dengue diagnostic codes at all VA facilities were identified using VA's Electronic Surveillance System for Early Notification of Community-based Epidemics (ESSENCE). Additional case sources included VA data from Centers for Disease Control and Prevention BioSense and VA infection preventionists. Case reviews were performed. Categorical data was compared using Mantel-Haenszel or Fisher Exact tests and continuous variables using t-tests. Dengue case residence was mapped.Two hundred eighty-eight and 21 PR and FL dengue cases respectively were identified. Of 21 FL cases, 12 were exposed in Key West and 9 were imported. During epidemic years, FL cases had significantly increased dengue testing and intensive care admissions, but lower hospitalization rates and headache or eye pain symptoms compared to PR cases. There were no significant differences in clinical symptoms, laboratory abnormalities or outcomes between epidemic and non-epidemic year cases in FL and PR. Confirmed/probable cases were significantly more likely to be hospitalized and have thrombocytopenia or leukopenia compared to suspected cases.Dengue re-introduction in the continental US warrants increased dengue surveillance and education in VA. Throughout VA, under-testing of suspected cases highlights the need to emphasize use of diagnostic testing to better understand the magnitude of dengue among Veterans.
View details for DOI 10.1371/journal.pntd.0002040
View details for Web of Science ID 000316943800005
View details for PubMedID 23516642
Immune biomarker differences and changes comparing HCV mono-infected, HIV/HCV co-infected, and HCV spontaneously cleared patients.
2013; 8 (4)
Immune biomarkers are implicated in HCV treatment response, fibrosis, and accelerated pathogenesis of comorbidities, though only D-dimer and C-reactive protein have been consistently studied. Few studies have evaluated HIV/HCV co-infection, and little longitudinal data exists describing a broader antiviral cytokine response.Fifty immune biomarkers were analyzed at baseline (BL) and HCV end of treatment follow-up(FU) time point using the Luminex 50-plex assay in plasma samples from 15 HCV-cleared, 24 HCV mono- and 49 HIV/HCV co-infected patients receiving antiretroviral treatment, who either did or did not receive pegylated-interferon/ribavirin HCV treatment. Biomarker levels were compared among spontaneous clearance patients, mono- and co-infected, untreated and HCV-treated, and sustained virologic responders (SVR) and non-responders (NR) at BL and FU using nonparametric analyses. A Bonferroni correction, adjusting for tests of 50 biomarkers, was used to reduce Type I error.Compared to HCV patients at BL, HIV/HCV patients had 22 significantly higher and 4 significantly lower biomarker levels, following correction for multiple testing. There were no significantly different BL levels when comparing SVR and NR in mono- or co-infected patients; however, FU levels changed considerably in co-infected patients, with seven becoming significantly higher and eight becoming significantly lower in SVR patients. Longitudinally between BL and FU, 13 markers significantly changed in co-infected SVR patients, while none significantly changed in co-infected NR patients. There were also no significant changes in longitudinal analyses of mono-infected patients achieving SVR or mono-infected and co-infected groups deferring treatment.Clear differences exist in pattern and quantity of plasma immune biomarkers among HCV mono-infected, HIV/HCV co-infected, and HCV-cleared patients; and with SVR in co-infected patients treated for HCV. Though >90% of patients were male and co-infected had a larger percentage of African American patients, our findings may have implications for better understanding HCV pathogenesis, treatment outcomes, and future therapeutic targets.
View details for DOI 10.1371/journal.pone.0060387
View details for PubMedID 23593207
Influenza treatment and prophylaxis with neuraminidase inhibitors: a review.
Infection and drug resistance
2013; 6: 187-198
Influenza virus is a pathogen that causes morbidity and mortality worldwide. Whereas vaccination is important for prevention of disease, given its limitations, antiviral therapy is at the forefront of treatment and also plays a role in prevention. Currently, two classes of antiviral medications, the adamantanes and the neuraminidase inhibitors, are approved for treatment. Given the resistance patterns of circulating influenza, adamantanes are not recommended. Within the US, two neuraminidase inhibitors are currently approved for both treatment and prevention, while worldwide there are four available. In this review, we will briefly discuss the epidemiology and pathology of influenza and then discuss neuraminidase inhibitors: their mechanism of action, resistance, development, and future applications.
View details for DOI 10.2147/IDR.S36601
View details for PubMedID 24277988
CD4 Counts and Mortality in Virologically Suppressed US Veterans.
Journal of the International Association of Providers of AIDS Care
We used the Veterans Health Administration (VA) HIV Clinical Case Registry (CCR) to evaluate the association between annual CD4 averages and all-cause mortality in HIV-infected veterans during their initial episode of suppressive highly active antiretroviral therapy (HAART). We observed 1083 deaths in 14 769 patients. Unadjusted mortality rates in the top and bottom CD4 quintiles differed significantly from the mid CD4 strata. Mortality in the top CD4 quintile (≥720 cells/mm(3)) was 14.1/1000 patient-years, 95% confidence interval (CI): 10.1-18.2, compared with 20.4 (CI: 15.5-25.3) in the next lower CD4 stratum (530-719 cells/mm(3)). This difference was significant in Cox proportional hazards model, controlling for demographics, hepatitis co-infections, low-level viremia, HAART adherence, and refill rates of individual antiretrovirals (HR: 1.4, CI: 1.13-1.73). Our results support early HAART initiation as advocated by the current US treatment guidelines for HIV infection.
View details for DOI 10.1177/2325957413512153
View details for PubMedID 24378517
GBV-C viremia and clinical events in advanced HIV infection.
Journal of medical virology
GB Virus C (GBV-C) is a non-pathogenic flavivirus, commonly found in HIV infected patients. Studies suggest a survival benefit of GBV-C viremia in HIV infection. Impact of GBV-C viremia was evaluated on clinical outcome in multidrug-resistant HIV. The OPTIMA study enrolled advanced multidrug-resistant HIV patients with a CD4 count ≤300 cells/mm(3) . This study included a subset of OPTIMA patients. Primary endpoints included AIDS events or death. GBV-C status was assessed at baseline and last time point on study by real-time PCR. Cox proportional hazards models were used to determine if CD4 count (>100/mm(3) ), treatment assignment, presence or disappearance of GBV-C viremia, GBV-C viral load level and Hepatitis C virus antibody status were associated with outcome. Of 288 patients (98% male, baseline mean age 48 years, HIV viral load 4.67 log10 /ml, and CD4 127 cells/mm(3) ), 62 (21.5%) had detectable GBV-C viremia. The mortality rate for GBV-C infected subjects was lower, 19/62 (30.7%) versus 87/226 (38.5%), and time to death shorter (HR 0.67, 95% CI 0.41-1.11), but the results were not significantly different. The time to development of AIDS events was not different (HR 0.90, 95% CI 0.52-1.53). Among covariates, only CD4 count (HR 0.28, CI 0.19-0.42) had a significant survival effect. A trend in decreased mortality was seen in GBV-C+ patients with CD4 <100/mm(3) in multivariate analyses. GBV-C co-infection in multidrug-resistant HIV infected patients was associated with a trend in improved survival but not decreased AIDS events. Analysis was limited by cohort size. J. Med. Virol. © 2013 Wiley Periodicals, Inc.
View details for DOI 10.1002/jmv.23845
View details for PubMedID 24249700
Combining Surveillance Systems: Effective Merging of U.S. Veteran and Military Health Data.
2013; 8 (12): e84077
The U.S. Department of Veterans Affairs (VA) and Department of Defense (DoD) had more than 18 million healthcare beneficiaries in 2011. Both Departments conduct individual surveillance for disease events and health threats.We performed joint and separate analyses of VA and DoD outpatient visit data from October 2006 through September 2010 to demonstrate geographic and demographic coverage, timeliness of influenza epidemic awareness, and impact on spatial cluster detection achieved from a joint VA and DoD biosurveillance platform.Although VA coverage is greater, DoD visit volume is comparable or greater. Detection of outbreaks was better in DoD data for 58% and 75% of geographic areas surveyed for seasonal and pandemic influenza, respectively, and better in VA data for 34% and 15%. The VA system tended to alert earlier with a typical H3N2 seasonal influenza affecting older patients, and the DoD performed better during the H1N1 pandemic which affected younger patients more than normal influenza seasons. Retrospective analysis of known outbreaks demonstrated clustering evidence found in separate DoD and VA runs, which persisted with combined data sets.The analyses demonstrate two complementary surveillance systems with evident benefits for the national health picture. Relative timeliness of reporting could be improved in 92% of geographic areas with access to both systems, and more information provided in areas where only one type of facility exists. Combining DoD and VA data enhances geographic cluster detection capability without loss of sensitivity to events isolated in either population and has a manageable effect on customary alert rates.
View details for DOI 10.1371/journal.pone.0084077
View details for PubMedID 24386335
Risk of cardiovascular disease from antiretroviral therapy for HIV: a systematic review.
2013; 8 (3)
Recent studies suggest certain antiretroviral therapy (ART) drugs are associated with increases in cardiovascular disease.We performed a systematic review and meta-analysis to summarize the available evidence, with the goal of elucidating whether specific ART drugs are associated with an increased risk of myocardial infarction (MI).We searched Medline, Web of Science, the Cochrane Library, and abstract archives from the Conference on Retroviruses and Opportunistic Infections and International AIDS Society up to June 2011 to identify published articles and abstracts.Eligible studies were comparative and included MI, strokes, or other cardiovascular events as outcomes.Eligibility screening, data extraction, and quality assessment were performed independently by two investigators.Random effects methods and Fisher's combined probability test were used to summarize evidence.Twenty-seven studies met inclusion criteria, with 8 contributing to a formal meta-analysis. Findings based on two observational studies indicated an increase in risk of MI for patients recently exposed (usually defined as within last 6 months) to abacavir (RR 1.92, 95% CI 1.51-2.42) and protease inhibitors (PI) (RR 2.13, 95% CI 1.06-4.28). Our analysis also suggested an increased risk associated with each additional year of exposure to indinavir (RR 1.11, 95% CI 1.05-1.17) and lopinavir (RR 1.22, 95% CI 1.01-1.47). Our findings of increased cardiovascular risk from abacavir and PIs were in contrast to four published meta-analyses based on secondary analyses of randomized controlled trials, which found no increased risk from cardiovascular disease.Although observational studies implicated specific drugs, the evidence is mixed. Further, meta-analyses of randomized trials did not find increased risk from abacavir and PIs. Our findings that implicate specific ARTs in the observational setting provide sufficient evidence to warrant further investigation of this relationship in studies designed for that purpose.
View details for DOI 10.1371/journal.pone.0059551
View details for PubMedID 23555704
IL28B polymorphism is not associated with HCV protease diversity in patients co-infected with HIV and HCV treated with pegylated interferon and ribavirin
JOURNAL OF MEDICAL VIROLOGY
2012; 84 (10): 1522-1527
Recent studies have demonstrated that IL28B polymorphisms predict therapeutic responses in chronic hepatitis C virus (HCV)-treated patients; however, the effect on HCV viral diversity, particularly on the HCV protease gene, is not clear. This study sought to evaluate the effect of IL28B polymorphisms on HCV diversity at NS3/4 protease region, which may influence therapeutic response to an HCV protease inhibitor based regimen. Twenty-two patients co-infected with HIV and HCV genotype 1, treatment-naïve on stable HIV antiretroviral therapy initiating interferon-based treatment were evaluated. Plasma HCV NS3 gene diversity was analyzed by clonal analysis at baseline and end of treatment. IL28B (rs12979860) genotypes were tested for associations with virologic outcomes and diversity parameters. There was similar baseline NS3 diversity in patients with CC (favorable) genotype compared to those with CT/TT (unfavorable) genotypes. There was no significant association between IL28B genotype and baseline NS3 nucleotide p-distance, dS-dN, amino acid p-distance, or nucleotide changes. Among patients without a sustained virologic response, between baseline and follow-up there was a significant trend towards decreased diversity after treatment among patients with favorable genotype, which was not observed in unfavorable genotypes. In patients treated with peginterferon/ribavirin therapy, IL28B polymorphism was not associated with enhanced NS3 diversity at baseline. Among non-SVR patients with the less favorable genotype, there was no change in diversity after treatment. This suggests that IL28B genotype is unlikely to have a negative impact on subsequent HCV PI efficacy in patients co-infected with HIV and HCV patients who have previously failed HCV therapy.
View details for DOI 10.1002/jmv.23376
View details for Web of Science ID 000308106500003
View details for PubMedID 22930497
Cost Effectiveness of Screening Strategies for Early Identification of HIV and HCV Infection in Injection Drug Users
2012; 7 (9)
To estimate the cost, effectiveness, and cost effectiveness of HIV and HCV screening of injection drug users (IDUs) in opioid replacement therapy (ORT).Dynamic compartmental model of HIV and HCV in a population of IDUs and non-IDUs for a representative U.S. urban center with 2.5 million adults (age 15-59).We considered strategies of screening individuals in ORT for HIV, HCV, or both infections by antibody or antibody and viral RNA testing. We evaluated one-time and repeat screening at intervals from annually to once every 3 months. We calculated the number of HIV and HCV infections, quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratios (ICERs).Adding HIV and HCV viral RNA testing to antibody testing averts 14.8-30.3 HIV and 3.7-7.7 HCV infections in a screened population of 26,100 IDUs entering ORT over 20 years, depending on screening frequency. Screening for HIV antibodies every 6 months costs $30,700/QALY gained. Screening for HIV antibodies and viral RNA every 6 months has an ICER of $65,900/QALY gained. Strategies including HCV testing have ICERs exceeding $100,000/QALY gained unless awareness of HCV-infection status results in a substantial reduction in needle-sharing behavior.Although annual screening for antibodies to HIV and HCV is modestly cost effective compared to no screening, more frequent screening for HIV provides additional benefit at less cost. Screening individuals in ORT every 3-6 months for HIV infection using both antibody and viral RNA technologies and initiating ART for acute HIV infection appears cost effective.
View details for DOI 10.1371/journal.pone.0045176
View details for Web of Science ID 000311313900091
View details for PubMedID 23028828
Development of Elvitegravir Resistance and Linkage of Integrase Inhibitor Mutations with Protease and Reverse Transcriptase Resistance Mutations
2012; 7 (7)
Failure of antiretroviral regimens containing elvitegravir (EVG) and raltegravir (RAL) can result in the appearance of integrase inhibitor (INI) drug-resistance mutations (DRMs). While several INI DRMs have been identified, the evolution of EVG DRMs and the linkage of these DRMs with protease inhibitor (PI) and reverse transcriptase inhibitor (RTI) DRMs have not been studied at the clonal level. We examined the development of INI DRMs in 10 patients failing EVG-containing regimens over time, and the linkage of INI DRMs with PI and RTI DRMs in these patients plus 6 RAL-treated patients. A one-step RT-nested PCR protocol was used to generate a 2.7 kB amplicon that included the PR, RT, and IN coding region, and standard cloning and sequencing techniques were used to determine DRMs in 1,277 clones (mean 21 clones per time point). Results showed all patients had multiple PI, NRTI, and/or NNRTI DRMs at baseline, but no primary INI DRM. EVG-treated patients developed from 2 to 6 strains with different primary INI DRMs as early as 2 weeks after initiation of treatment, predominantly as single mutations. The prevalence of these strains fluctuated and new strains, and/or strains with new combinations of INI DRMs, developed over time. Final failure samples (weeks 14 to 48) typically showed a dominant strain with multiple mutations or N155H alone. Single N155H or multiple mutations were also observed in RAL-treated patients at virologic failure. All patient strains showed evidence of INI DRM co-located with single or multiple PI and/or RTI DRMs on the same viral strand. Our study shows that EVG treatment can select for a number of distinct INI-resistant strains whose prevalence fluctuates over time. Continued appearance of new INI DRMs after initial INI failure suggests a potent, highly dynamic selection of INI resistant strains that is unaffected by co-location with PI and RTI DRMs.
View details for DOI 10.1371/journal.pone.0040514
View details for Web of Science ID 000306548900028
View details for PubMedID 22815755
Predictive value of HIV-1 replication capacity and phenotypic susceptibility scores in antiretroviral treatment-experienced patients
2012; 13 (6): 345-351
The aim of the study was to determine the prognostic value of HIV replication capacity (RC) for subsequent antiretroviral (ARV) treatment response in ARV-experienced patients.RC and phenotypic resistance testing were performed at baseline and week 12 on plasma samples from patients randomized to undergo a 12-week ARV drug-free period (ARDFP) or initiate immediate salvage therapy (no-ARDFP group) in the Options in Management with Antiretrovirals (OPTIMA) trial. Dichotomous and incremental phenotypic susceptibility scores (dPSSs and iPSSs, respectively) were calculated. The predictive value of RC and PSS for ARV therapy response and/or ARDFP was evaluated using multivariate regression analysis and Pearson correlations.In 146 no-ARDFP subjects, baseline RC (50.8%) did not change at week 12 and was not correlated with CD4 cell count or viral load changes at week 12 (P=0.33 and P=0.79, respectively) or at week 24 (P=0.96 and P=0.14, respectively). dPSS predicted virological but not CD4 cell count response to ARV therapy at weeks 12, 24 and 48 (P=0.002, P<0.001 and P=0.005, respectively). RC was significantly correlated with dPSS and iPSS at baseline, but did not increase their predictive value. In the 137 ARDFP patients, RC increased significantly (from 52.4 to 85.8%), but did not predict CD4 cell count and viral load changes during ARDFP (P=0.92 and P=0.26, respectively). RC after ARDFP did not predict subsequent CD4 cell count and viral load changes 12 weeks following ARV treatment reinitiation (P=0.90 and P=0.29, respectively).We found no additional predictive value of replication capacity for virological or immunological responses (above what PSS provides) in patients undergoing salvage ARV treatment.
View details for DOI 10.1111/j.1468-1293.2011.00981.x
View details for Web of Science ID 000304762200004
View details for PubMedID 22276745
Results from a Large-Scale Epidemiologic Look-Back Investigation of Improperly Reprocessed Endoscopy Equipment
INFECTION CONTROL AND HOSPITAL EPIDEMIOLOGY
2012; 33 (7): 649-656
To determine whether improper high-level disinfection practices during endoscopy procedures resulted in bloodborne viral infection transmission.?Retrospective cohort study.?Four Veterans Affairs medical centers (VAMCs).?Veterans who underwent colonoscopy and laryngoscopy (ear, nose, and throat [ENT]) procedures from 2003 to 2009.?Patients were identified through electronic health record searches and serotested for human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV). Newly discovered case patients were linked to a potential source with known identical infection, whose procedure occurred no more than 1 day prior to the case patient's procedure. Viral genetic testing was performed for case/proximate pairs to determine relatedness.?Of 10,737 veterans who underwent endoscopy at 4 VAMCs, 9,879 patients agreed to viral testing. Of these, 90 patients were newly diagnosed with 1 or more viral bloodborne pathogens (BBPs). There were no case/proximate pairings found for patients with either HIV or HBV; 24 HCV case/proximate pairings were found, of which 7 case patients and 8 proximate patients had sufficient viral load for further genetic testing. Only 2 of these cases, both of whom underwent laryngoscopy, and their 4 proximates agreed to further testing. None of the 4 remaining proximate patients who underwent colonoscopy agreed to further testing. Mean genetic distance between the 2 case patients and 4 proximate patients ranged from 13.5% to 19.1%.?Our investigation revealed that exposure to improperly reprocessed ENT endoscopes did not result in viral transmission in those patients who had viral genetic analysis performed. Any potential transmission of BBPs from colonoscopy remains unknown.
View details for DOI 10.1086/666345
View details for Web of Science ID 000304998300001
View details for PubMedID 22669224
Comparative Assessment of Antimicrobial Usage Measures in the Department of Veterans Affairs
INFECTION CONTROL AND HOSPITAL EPIDEMIOLOGY
2012; 33 (4): 409-411
We compared 2 data sources--antimicrobial orders and bar-coded medication administration (BCMA)--for calculating the number of grams used, grams used based on defined daily dose, and days of therapy at one Veterans Affairs Medical Center for 2009-2010. The number of grams used calculated from BCMA data provided the most informative antimicrobial utilization measure.
View details for DOI 10.1086/664759
View details for Web of Science ID 000301716700016
View details for PubMedID 22418639
Outcomes Associated with a Cognitive-Behavioral Chronic Pain Management Program Implemented in Three Public HIV Primary Care Clinics
JOURNAL OF BEHAVIORAL HEALTH SERVICES & RESEARCH
2012; 39 (2): 158-173
In patients with HIV/AIDS, chronic pain is common and analgesics pose serious risks. Cognitive-behavioral therapies (CBT) provide an alternative. This study evaluated feasibility and impact of a CBT-based pain management program in three public primary care clinics for HIV patients. The program included a workbook and 12-weeks of group CBT sessions. HIV-positive patients with chronic moderate to severe pain were invited to participate in the program and were assessed at enrollment, 6, 12, and 24 weeks. Despite only moderate group attendance, program enrollment was associated with significant improvements in pain intensity, pain-related functioning, anxiety and acceptance, and mental health. At 24 weeks, effect sizes for pain outcomes were -0.83 for pain intensity and -0.43 for functioning. The pattern of change in outcomes was consistent with predictions based on cognitive-behavioral theory. Effects were observed at all clinics. Adding CBT-based pain management into primary care may provide important benefits for patients with HIV/AIDS.
View details for Web of Science ID 000303000000006
View details for PubMedID 21947662
Quantitation of hepatitis C virus RNA in peripheral blood mononuclear cells in HCV-monoinfection and HIV/HCV-coinfection
JOURNAL OF MEDICAL VIROLOGY
2012; 84 (3): 431-437
Peripheral blood mononuclear cells (PBMCs) represent an extrahepatic hepatitis C virus (HCV) reservoir, the significance of which is unclear due to limited studies and varying test methodologies. In this study, a commercial viral load assay for measuring cell-associated PBMC HCV RNA was evaluated. HCV RNA was extracted from PBMCs, sorted CD14+, and CD19+ cells and corresponding plasma samples using the Abbott m2000 and Real-Time HCV assay. Test performance and influence of HIV seropositivity on plasma and PBMC HCV RNA were studied. Among 51 patients, 67 and 62 unique patient samples had detectable plasma and PBMC HCV viral load, respectively. The median PBMC viral load was 535?IU/1?M cells (range 29-5,190). CD19+ cells had significantly higher viral load than CD14+ cells (median log(10) HCV viral load 2.63 vs. 1.50?IU/ml; P< 0.001). Stability of PBMC viral load over time was demonstrated in untreated patients; all patients with an undetectable plasma HCV viral load after HCV treatment also demonstrated undetectable PBMC viral load. Repeated testing in nine samples yielded consistent PBMC viral load, differing by only 1.3-fold (range 1.0-1.7-fold). Among samples with detectable plasma HCV RNA, the correlation between PBMC and plasma viral load was moderate (r?=?0.66) and was greater among HCV mono-infected compared to HIV/HCV co-infected subjects (r?=?0.80 vs. 0.52). Measurement of cell-associated PBMC HCV RNA using a commercial assay demonstrated promising test characteristics. Differences in PBMC HCV viral load based on HIV-coinfection status and the significance of greater copy number in B-cells requires further study.
View details for DOI 10.1002/jmv.23210
View details for Web of Science ID 000299071300008
View details for PubMedID 22246828
New Protease Inhibitors for the Treatment of Chronic Hepatitis C A Cost-Effectiveness Analysis
ANNALS OF INTERNAL MEDICINE
2012; 156 (4): 279-U68
Chronic hepatitis C virus is difficult to treat and affects approximately 3 million Americans. Protease inhibitors increase the effectiveness of standard therapy, but they are costly. A genetic assay may identify patients most likely to benefit from this treatment advance.To assess the cost-effectiveness of new protease inhibitors and an interleukin (IL)-28B genotyping assay for treating chronic hepatitis C virus.Decision-analytic Markov model.Published literature and expert opinion.Treatment-naive patients with chronic, genotype 1 hepatitis C virus monoinfection.Lifetime.Societal.Strategies are defined by the use of IL-28B genotyping and type of treatment (standard therapy [pegylated interferon with ribavirin]; triple therapy [standard therapy and a protease inhibitor]). Interleukin-28B-guided triple therapy stratifies patients with CC genotypes to standard therapy and those with non-CC types to triple therapy.Discounted costs (in 2010 U.S. dollars) and quality-adjusted life-years (QALYs); incremental cost-effectiveness ratios.For patients with mild and advanced fibrosis, universal triple therapy reduced the lifetime risk for hepatocellular carcinoma by 38% and 28%, respectively, and increased quality-adjusted life expectancy by 3% and 8%, respectively, compared with standard therapy. Gains from IL-28B-guided triple therapy were smaller. If the protease inhibitor costs $1100 per week, universal triple therapy costs $102,600 per QALY (mild fibrosis) or $51,500 per QALY (advanced fibrosis) compared with IL-28B-guided triple therapy and $70,100 per QALY (mild fibrosis) and $36,300 per QALY (advanced fibrosis) compared with standard therapy.Results were sensitive to the cost of protease inhibitors and treatment adherence rates.Data on the long-term comparative effectiveness of the new protease inhibitors are lacking.Both universal triple therapy and IL-28B-guided triple therapy are cost-effective when the least-expensive protease inhibitor are used for patients with advanced fibrosis.Stanford University.
View details for Web of Science ID 000300607600005
View details for PubMedID 22351713
Ultrasensitive detection of rare mutations using next-generation targeted resequencing
NUCLEIC ACIDS RESEARCH
2012; 40 (1)
With next-generation DNA sequencing technologies, one can interrogate a specific genomic region of interest at very high depth of coverage and identify less prevalent, rare mutations in heterogeneous clinical samples. However, the mutation detection levels are limited by the error rate of the sequencing technology as well as by the availability of variant-calling algorithms with high statistical power and low false positive rates. We demonstrate that we can robustly detect mutations at 0.1% fractional representation. This represents accurate detection of one mutant per every 1000 wild-type alleles. To achieve this sensitive level of mutation detection, we integrate a high accuracy indexing strategy and reference replication for estimating sequencing error variance. We employ a statistical model to estimate the error rate at each position of the reference and to quantify the fraction of variant base in the sample. Our method is highly specific (99%) and sensitive (100%) when applied to a known 0.1% sample fraction admixture of two synthetic DNA samples to validate our method. As a clinical application of this method, we analyzed nine clinical samples of H1N1 influenza A and detected an oseltamivir (antiviral therapy) resistance mutation in the H1N1 neuraminidase gene at a sample fraction of 0.18%.
View details for DOI 10.1093/nar/gkr861
View details for Web of Science ID 000298733500002
View details for PubMedID 22013163
Effect of Treatment Interruption and Intensification of Antiretroviral Therapy on Health-Related Quality of Life in Patients with Advanced HIV: A Randomized, Controlled Trial
MEDICAL DECISION MAKING
2012; 32 (1): 70-82
The effect of antiretroviral therapy (ART) interruption or intensification on health-related quality of life (HRQoL) in advanced HIV patients is unknown.To assess the impact of temporary treatment interruption and intensification of ART on HRQoL.A 2 x 2 factorial open label randomized controlled trial.Hospitals in the United States, Canada, and the United Kingdom.Multidrug resistant (MDR) HIV patients.Patients were randomized to receive a 12-wk interruption or not, and ART intensification or standard ART.The Health Utilities Index (HUI3), EQ-5D, standard gamble (SG), time tradeoff (TTO), visual analog scale (VAS), and the Medical Outcomes Study HIV Health Survey (MOS-HIV).There were no significant differences in HRQoL among the four groups during follow-up; however, there was a temporary significant decline in HRQoL on some measures within the interruption group during interruption (HUI3 -0.05, P = 0.03; VAS -5.9, P = 0.002; physical health summary -2.9, P = 0.001; mental health summary -1.9, P = 0.02). Scores declined slightly overall during follow-up. Multivariate analysis showed significantly lower HRQoL associated with some clinical events. Limitations. The results may not apply to HIV patients who have not experienced multiple treatment failures or who have not developed MDR HIV.Temporary ART interruption and ART intensification provided neither superior nor inferior HRQoL compared with no interruption and standard ART. Among surviving patients, HRQoL scores declined only slightly over years of follow-up in this advanced HIV cohort; however, approximately one-third of patients died during the trial follow up. Lower HRQoL was associated with adverse clinical events.
View details for DOI 10.1177/0272989X10397615
View details for Web of Science ID 000299701100011
View details for PubMedID 21383086
HIV-HBV vaccine escape mutant infection with loss of HBV surface antibody and persistent HBV viremia on tenofovir/emtricitabine without antiviral resistance
JOURNAL OF CLINICAL VIROLOGY
2011; 52 (3): 261-264
We report a case of acute hepatitis B virus genotype A vaccine escape mutant infection with loss of HBV vaccine-induced seropositivity in a HIV-1 infected patient. His HBV is unresponsive to tenofovir/emtricitabine treatment demonstrated by persistent viremia despite lacking known resistance mutations and while having an undetectable HIV-1 viral load.
View details for DOI 10.1016/j.jcv.2011.07.014
View details for Web of Science ID 000296556800021
View details for PubMedID 21840252
Use of dried clinical samples for storing and detecting influenza RNA
INFLUENZA AND OTHER RESPIRATORY VIRUSES
2011; 5 (6): 413-417
Most clinical samples collected for diagnostic influenza testing and monitoring require refrigerated or frozen storage or shipment, which imparts logistic and cost burdens. The ability to store and ship dried clinical specimens under ambient conditions for influenza testing would significantly reduce costs and protect samples from improper storage or equipment failure, especially in remote or resource-limited areas.To evaluate the collection and storage of dried clinical samples on a transport matrix (ViveST™, ST) for influenza RNA testing by real-time reverse-transcription PCR (RT-PCR).Viral transport medium from swab or sputum samples was applied to ST, dried, and stored under ambient conditions from 2 days to 6 months. Additional aliquots of samples were frozen. Testing of frozen and ST-stored samples was performed using the WHO/CDC real-time influenza A (H1N1) RT-PCR protocol and compared to the Luminex xTAG RVP assay.ST-stored samples yielded slightly higher threshold cycle values (median 2·54 cycles) compared to frozen samples tested in parallel. This difference was consistent regardless of viral input. There was no significant difference in signal recovery between samples stored for 1 week versus samples stored for 3 weeks, or from three samples stored for 6 months. Qualitatively, clinical specimens stored on ST were 100% concordant (36/36) with frozen samples for detecting the presence of influenza A RNA.ST-processed dried specimens produced similar rates of seasonal or novel 2009 HIN1 influenza RNA detection compared to conventional sample processing and thus presents a viable alternative to refrigerated or frozen samples.
View details for DOI 10.1111/j.1750-2659.2011.00253.x
View details for Web of Science ID 000296080300009
View details for PubMedID 21668673
Diagnosing invasive fungal disease in critically ill patients
CRITICAL REVIEWS IN MICROBIOLOGY
2011; 37 (4): 277-312
Fungal infections are increasing, with a changing landscape of pathogens and emergence of new groups at risk for invasive disease. We review current diagnostic techniques, focusing on studies in critically ill patients. Microbiological cultures, the current "gold standard", demonstrate poor sensitivity, thus diagnosis of invasive disease in the critically ill is difficult. This diagnostic dilemma results in under- or over-treatment of patients, potentially contributing to poor outcomes and antifungal resistance. While other current diagnostic tests perform moderately well, many lack timeliness, efficacy, and are negatively affected by treatments common to critically ill patients. New nucleic acid-based research is promising.
View details for DOI 10.3109/1040841X.2011.581223
View details for Web of Science ID 000295616800001
View details for PubMedID 21749278
Enhanced health event detection and influenza surveillance using a joint Veterans Affairs and Department of Defense biosurveillance application
BMC MEDICAL INFORMATICS AND DECISION MAKING
The establishment of robust biosurveillance capabilities is an important component of the U.S. strategy for identifying disease outbreaks, environmental exposures and bioterrorism events. Currently, U.S. Departments of Defense (DoD) and Veterans Affairs (VA) perform biosurveillance independently. This article describes a joint VA/DoD biosurveillance project at North Chicago-VA Medical Center (NC-VAMC). The Naval Health Clinics-Great Lakes facility physically merged with NC-VAMC beginning in 2006 with the full merger completed in October 2010 at which time all DoD care and medical personnel had relocated to the expanded and remodeled NC-VAMC campus and the combined facility was renamed the Lovell Federal Health Care Center (FHCC). The goal of this study was to evaluate disease surveillance using a biosurveillance application which combined data from both populations.A retrospective analysis of NC-VAMC/Lovell FHCC and other Chicago-area VAMC data was performed using the ESSENCE biosurveillance system, including one infectious disease outbreak (Salmonella/Taste of Chicago-July 2007) and one weather event (Heat Wave-July 2006). Influenza-like-illness (ILI) data from these same facilities was compared with CDC/Illinois Sentinel Provider and Cook County ESSENCE data for 2007-2008.Following consolidation of VA and DoD facilities in North Chicago, median number of visits more than doubled, median patient age dropped and proportion of females rose significantly in comparison with the pre-merger NC-VAMC facility. A high-level gastrointestinal alert was detected in July 2007, but only low-level alerts at other Chicago-area VAMCs. Heat-injury alerts were triggered for the merged facility in June 2006, but not at the other facilities. There was also limited evidence in these events that surveillance of the combined population provided utility above and beyond the VA-only and DoD-only components. Recorded ILI activity for NC-VAMC/Lovell FHCC was more pronounced in the DoD component, likely due to pediatric data in this population. NC-VAMC/Lovell FHCC had two weeks of ILI activity exceeding both the Illinois State and East North Central Regional baselines, whereas Hines VAMC had one and Jesse Brown VAMC had zero.Biosurveillance in a joint VA/DoD facility showed potential utility as a tool to improve surveillance and situational awareness in an area with Veteran, active duty and beneficiary populations. Based in part on the results of this pilot demonstration, both agencies have agreed to support the creation of a combined VA/DoD ESSENCE biosurveillance system which is now under development.
View details for DOI 10.1186/1472-6947-11-56
View details for Web of Science ID 000295781100001
View details for PubMedID 21929813
Determinants of the Cost of Health Services Used by Veterans With HIV
2011; 49 (9): 848-856
The effect of adherence, treatment failure, and comorbidities on the cost of HIV care is not well understood.To characterize the cost of HIV care including combination antiretroviral treatment (ART).Observational study of administrative data.Total 1896 randomly selected HIV-infected patients and 288 trial participants with multidrug-resistant HIV seen at the US Veterans Health Administration (VHA).Comorbidities, cost, pharmacy, and laboratory data.Many HIV-infected patients (24.5%) of the random sample did not receive ART. Outpatient pharmacy accounted for 62.8% of the costs of patients highly adherent with ART, 32.2% of the cost of those with lower adherence, and 6.2% of the cost of those not receiving ART. Compared with patients not receiving ART, high adherence was associated with lower hospital cost, but no greater total cost. Individuals with a low CD4 count (<50 cells/mm) incurred 1.9 times the cost of patients with counts >500. Most patients had medical, psychiatric, or substance abuse comorbidities. These conditions were associated with greater cost. Trial participants were less likely to have psychiatric and substance abuse comorbidities than the random sample of VHA patients with HIV.Patients receiving combination ART had higher medication costs but lower acute hospital cost. Poor control of HIV was associated with higher cost. The cost of psychiatric, substance abuse, rehabilitation, and long-term care and medications other than ART, often overlooked in HIV studies, was substantial.
View details for DOI 10.1097/MLR.0b013e31821b34c0
View details for Web of Science ID 000294206700015
View details for PubMedID 21610542
Interferon combination therapy for HIV/hepatitis C virus coinfection
2011; 3 (9): 1087-1102
IFN-? has been the cornerstone of chronic hepatitis C virus (HCV) treatment for over a decade. Yet, rates of sustained virologic response of HCV infection to interferon-based therapy, particularly in difficult-to-treat populations, have been disappointingly low. This is particularly true in HIV/HCV coinfection, in which less than a third of patients typically respond to therapy. New HCV protease inhibitors, most of which will need to be administered with pegylated interferon, are in development, but comprehensive, long-term data for their use in coinfected patients is not yet available. Understanding the basis of this population's poor response to interferon-based therapy is crucial to future exploration of new therapeutic options, immunotherapy and prognosis in HIV/HCV-coinfected population.
View details for DOI 10.2217/IMT.11.105
View details for Web of Science ID 000296293800011
View details for PubMedID 21913831
One-year outcomes of community-acquired and healthcare-associated pneumonia in the Veterans Affairs Healthcare System
INTERNATIONAL JOURNAL OF INFECTIOUS DISEASES
2011; 15 (6): E382-E387
While studies have demonstrated higher medium-term mortality for community-acquired pneumonia (CAP), mortality and costs have not been characterized for healthcare-associated pneumonia (HCAP) over a 1-year period.We conducted a retrospective cohort study to evaluate mortality rates and health system costs for patients with CAP or HCAP during initial hospitalization and for 1 year after hospital discharge. We selected 50 758 patients admitted to the Veterans Affairs (VA) healthcare system between October 2003 and May 2007. Main outcome measures included hospital, post-discharge, and cumulative mortality rates and cost during initial hospitalization and at 12 months following discharge.Hospital and 1-year HCAP mortality were nearly twice that of CAP. HCAP was an independent predictor for hospital mortality (odds ratio (OR) 1.62, 95% confidence interval (CI) 1.49-1.76) and 1-year mortality (OR 1.99, 95% CI 1.87-2.11) when controlling for demographics, comorbidities, pneumonia severity, and factors associated with multidrug-resistant infection, including immune suppression, previous antibiotic treatment, and aspiration pneumonia. HCAP patients consistently had higher mortality in each stratum of the Charlson-Deyo-Quan comorbidity index. HCAP patients incurred significantly greater cost during the initial hospital stay and in the following 12 months. Demographics and comorbid conditions, particularly aspiration pneumonia, accounted for 19-33% of this difference.HCAP represents a distinct category of pneumonia with particularly poor survival up to 1 year after hospital discharge. While comorbidities, pneumonia severity, and risk factors for multidrug-resistant infection may interact to produce even higher mortality compared to CAP, they alone do not explain the observed differences.
View details for DOI 10.1016/j.ijid.2011.02.002
View details for Web of Science ID 000290588800003
View details for PubMedID 21393043
Clinically Significant Drug Interactions in Younger and Older Human Immunodeficiency Virus-Positive Patients Receiving Antiretroviral Therapy
2011; 31 (5): 480-489
To characterize clinically significant drug interactions (CSDIs) in younger and older human immunodeficiency virus (HIV)-positive patients who were receiving antiretroviral therapy.Retrospective medical record review.HIV specialty clinic at a Veterans Affairs medical center.A total of 110 younger (age < 50 yrs) and older (age ? 50 yrs) HIV-positive patients receiving antiretroviral therapy during 2007.Demographic, clinical, and prescription drug data were collected. Pharmacokinetic and pharmacodynamic drug interactions were identified, assigned a severity grade, and evaluated for management according to two sources. Interactions with a grade of 2 (monitoring or timing of doses recommended), 3 (therapy modification recommended), or 4 (contraindicated) were considered CSDIs. Among 36 younger and 74 older patients, 763 CSDIs were identified. At least one CSDI was present in 83.3% and 89.2% of younger and older patients, respectively (p=0.56), with most having both antiretroviral and nonantiretroviral CSDIs. Younger and older patients, respectively, had a median of 3 and 5.5 total CSDIs/patient (p=0.09), 2 and 3 antiretroviral CSDIs/patient (p=0.65), and 0.5 and 2.5 nonantiretroviral CSDIs/patient (p=0.04). The proportions of grade 2, 3, and 4 CSDIs were 74.1%, 25.0%, and 0.9%, respectively, in younger patients and 73.1%, 26.1%, and 0.7%, respectively, in older patients (p=0.92). Younger patients had more CSDIs involving antihistamine, erectile dysfunction, and hormone or corticosteroid agents (p<0.01), whereas older patients had more CSDIs involving antihypertensive and antidiabetic agents (p<0.001). Management and outcomes of grades 3 and 4 antiretroviral CSDIs did not differ significantly by age. A list of frequently mismanaged interactions is provided.Clinically significant drug interactions were prevalent in younger and older HIV-positive patients receiving antiretroviral therapy, among which nonantiretroviral interactions should not be overlooked. Knowledge of the drug classes frequently involved in CSDIs by age group and types of CSDIs that are commonly mismanaged may help clinicians optimize care for HIV-infected patients.
View details for Web of Science ID 000290184000005
View details for PubMedID 21923429
Results of Antiretroviral Treatment Interruption and Intensification in Advanced Multi-Drug Resistant HIV Infection from the OPTIMA Trial
2011; 6 (3)
Guidance is needed on best medical management for advanced HIV disease with multidrug resistance (MDR) and limited retreatment options. We assessed two novel antiretroviral (ARV) treatment approaches in this setting.We conducted a 2×2 factorial randomized open label controlled trial in patients with a CD4 count?300 cells/µl who had ARV treatment (ART) failure requiring retreatment, to two options (a) re-treatment with either standard (?4 ARVs) or intensive (?5 ARVs) ART and b) either treatment starting immediately or after a 12-week monitored ART interruption. Primary outcome was time to developing a first AIDS-defining event (ADE) or death from any cause. Analysis was by intention to treat. From 2001 to 2006, 368 patients were randomized. At baseline, mean age was 48 years, 2% were women, median CD4 count was 106/µl, mean viral load was 4.74 log(10) copies/ml, and 59% had a prior AIDS diagnosis. Median follow-up was 4.0 years in 1249 person-years of observation. There were no statistically significant differences in the primary composite outcome of ADE or death between re-treatment options of standard versus intensive ART (hazard ratio 1.17; CI 0.86-1.59), or between immediate retreatment initiation versus interruption before re-treatment (hazard ratio 0.93; CI 0.68-1.30), or in the rate of non-HIV associated serious adverse events between re-treatment options.We did not observe clinical benefit or harm assessed by the primary outcome in this largest and longest trial exploring both ART interruption and intensification in advanced MDR HIV infection with poor retreatment options.Clinicaltrials.gov NCT00050089.
View details for DOI 10.1371/journal.pone.0014764
View details for Web of Science ID 000289057200001
View details for PubMedID 21483491
Integrating Tobacco Cessation Into Mental Health Care for Posttraumatic Stress Disorder A Randomized Controlled Trial
JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION
2010; 304 (22): 2485-2493
Most smokers with mental illness do not receive tobacco cessation treatment.To determine whether integrating smoking cessation treatment into mental health care for veterans with posttraumatic stress disorder (PTSD) improves long-term smoking abstinence rates.A randomized controlled trial of 943 smokers with military-related PTSD who were recruited from outpatient PTSD clinics at 10 Veterans Affairs medical centers and followed up for 18 to 48 months between November 2004 and July 2009.Smoking cessation treatment integrated within mental health care for PTSD delivered by mental health clinicians (integrated care [IC]) vs referral to Veterans Affairs smoking cessation clinics (SCC). Patients received smoking cessation treatment within 3 months of study enrollment.Smoking outcomes included 12-month bioverified prolonged abstinence (primary outcome) and 7- and 30-day point prevalence abstinence assessed at 3-month intervals. Amount of smoking cessation medications and counseling sessions delivered were tested as mediators of outcome. Posttraumatic stress disorder and depression were repeatedly assessed using the PTSD Checklist and Patient Health Questionnaire 9, respectively, to determine if IC participation or quitting smoking worsened psychiatric status.Integrated care was better than SCC on prolonged abstinence (8.9% vs 4.5%; adjusted odds ratio, 2.26; 95% confidence interval [CI], 1.30-3.91; P = .004). Differences between IC vs SCC were largest at 6 months for 7-day point prevalence abstinence (78/472 [16.5%] vs 34/471 [7.2%], P < .001) and remained significant at 18 months (86/472 [18.2%] vs 51/471 [10.8%], P < .001). Number of counseling sessions received and days of cessation medication used explained 39.1% of the treatment effect. Between baseline and 18 months, psychiatric status did not differ between treatment conditions. Posttraumatic stress disorder symptoms for quitters and nonquitters improved. Nonquitters worsened slightly on the Patient Health Questionnaire 9 relative to quitters (differences ranged between 0.4 and 2.1, P = .03), whose scores did not change over time.Among smokers with military-related PTSD, integrating smoking cessation treatment into mental health care compared with referral to specialized cessation treatment resulted in greater prolonged abstinence.clinicaltrials.gov Identifier: NCT00118534.
View details for Web of Science ID 000285053300022
View details for PubMedID 21139110
Comparative effectiveness of dried plasma HIV-1 viral load testing in Brazil using ViveST for sample collection
JOURNAL OF CLINICAL VIROLOGY
2010; 49 (4): 245-248
Utilization of dried plasma for HIV-1 viral load testing would significantly decrease sample shipping costs.To describe the precision and reproducibility of ViveST(®) (ST) as a transportation method for shipping specimens for HIV-1 viral load (VL) testing.Thirty clinical plasma samples were used to generate replicate samples with HIV VL values of 4 log(10), 3 log(10) and 2 log(10) copies/mL for reproducibility testing and an additional 299 samples with HIV VL <50 copies/mL (99); 1.7 log(10) to 3.99 log(10) (100); and 4 log(10) to 5.99 log(10)/mL (100) were used to compare ViveST to frozen plasma samples using the VERSANT(®) HIV-1 RNA 3.0 Assay. Results were compared using Student t-test, Pearson correlation and Bland-Altman analyses.Mean intra-assay variance among frozen and dried plasma triplicates was 0.15 log(10) and 0.09 log(10) copies/mL respectively (n=10, P=NS). Compared to frozen plasma, there was a mean reduction of 0.3 log(10), 0.27 log(10), and 0.35 log(10) copies/mL at the 4 log(10), 3 log(10), and 2 log(10) copy/mL samples respectively (n=30, all comparisons, P<0.01). Overall correlation between 299 frozen and ViveST samples was r=0.97, where 12 of 99 undetectable frozen VL were positive with ST, and 12 of 200 frozen detectable VL were undetectable with ViveST (mean VL 2.1, 1.9 log(10) copies/mL respectively).HIV-1 viral load results using ViveST were reproducible, correlated well with frozen plasma, though yielding minimally lower values. Our data suggest that dried plasma for HIV-1 VL testing using ViveST has promise for use in HIV clinical practice.
View details for DOI 10.1016/j.jcv.2010.08.017
View details for Web of Science ID 000284105300004
View details for PubMedID 20880740
Effect of Home Testing of International Normalized Ratio on Clinical Events.
NEW ENGLAND JOURNAL OF MEDICINE
2010; 363 (17): 1608-1620
Warfarin anticoagulation reduces thromboembolic complications in patients with atrial fibrillation or mechanical heart valves, but effective management is complex, and the international normalized ratio (INR) is often outside the target range. As compared with venous plasma testing, point-of-care INR measuring devices allow greater testing frequency and patient involvement and may improve clinical outcomes.We randomly assigned 2922 patients who were taking warfarin because of mechanical heart valves or atrial fibrillation and who were competent in the use of point-of-care INR devices to either weekly self-testing at home or monthly high-quality testing in a clinic. The primary end point was the time to a first major event (stroke, major bleeding episode, or death).The patients were followed for 2.0 to 4.75 years, for a total of 8730 patient-years of follow-up. The time to the first primary event was not significantly longer in the self-testing group than in the clinic-testing group (hazard ratio, 0.88; 95% confidence interval, 0.75 to 1.04; P=0.14). The two groups had similar rates of clinical outcomes except that the self-testing group reported more minor bleeding episodes. Over the entire follow-up period, the self-testing group had a small but significant improvement in the percentage of time during which the INR was within the target range (absolute difference between groups, 3.8 percentage points; P<0.001). At 2 years of follow-up, the self-testing group also had a small but significant improvement in patient satisfaction with anticoagulation therapy (P=0.002) and quality of life (P<0.001).As compared with monthly high-quality clinic testing, weekly self-testing did not delay the time to a first stroke, major bleeding episode, or death to the extent suggested by prior studies. These results do not support the superiority of self-testing over clinic testing in reducing the risk of stroke, major bleeding episode, and death among patients taking warfarin therapy. (Funded by the Department of Veterans Affairs Cooperative Studies Program; ClinicalTrials.gov number, NCT00032591.).
View details for Web of Science ID 000283242700005
View details for PubMedID 20961244
An evaluation of patient self-testing competency of prothrombin time for managing anticoagulation: pre-randomization results of VA Cooperative Study #481-The Home INR Study (THINRS)
JOURNAL OF THROMBOSIS AND THROMBOLYSIS
2010; 30 (3): 263-275
Prior studies suggest patient self-testing (PST) of prothrombin time (PT) can improve the quality of anticoagulation (AC) and reduce complications (e.g., bleeding and thromboembolic events). "The Home INR Study" (THINRS) compared AC management with frequent PST using a home monitoring device to high-quality AC management (HQACM) with clinic-based monitoring on major health outcomes. A key clinical and policy question is whether and which patients can successfully use such devices. We report the results of Part 1 of THINRS in which patients and caregivers were evaluated for their ability to perform PST. Study-eligible patients (n = 3643) were trained to use the home monitoring device and evaluated after 2-4 weeks for PST competency. Information about demographics, medical history, warfarin use, medications, plus measures of numeracy, literacy, cognition, dexterity, and satisfaction with AC were collected. Approximately 80% (2931 of 3643) of patients trained on PST demonstrated competency; of these, 8% (238) required caregiver assistance. Testers who were not competent to perform PST had higher numbers of practice attempts, higher cuvette wastage, and were less able to perform a fingerstick or obtain blood for the cuvette in a timely fashion. Factors associated with failure to pass PST training included increased age, previous stroke history, poor cognition, and poor manual dexterity. A majority of patients were able to perform PST. Successful home monitoring of PT with a PST device required adequate levels of cognition and manual dexterity. Training a caregiver modestly increased the proportion of patients who can perform PST.
View details for DOI 10.1007/s11239-010-0499-8
View details for Web of Science ID 000282215300002
View details for PubMedID 20628787
Maternal-Fetal Pharmacokinetics and Dynamics of a Single Intrapartum Dose of Maraviroc in Rhesus Macaques
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
2010; 54 (10): 4059-4063
Single-dose nevirapine (NVP) is effective in reducing mother-to-child transmission (MTCT) of HIV; however, the subsequent development of drug resistance is problematic. The pharmacokinetic profile of the HIV entry inhibitor maraviroc after a single intrapartum dose in rhesus macaques was studied to determine whether maraviroc could serve as an alternative to NVP in a single-dose strategy. Four pregnant macaques received an oral dose of maraviroc 2 h before delivery, and both infant and maternal plasma maraviroc concentrations and CCR5 receptor occupancy on CD4(+) lymphocytes were measured over time. Maximum plasma maraviroc concentrations were found at delivery (2-h-postintrapartum dose) in both the mothers and infants, with median concentrations of 974 ng/ml (range, 86 to 2,830 ng/ml) and 22 ng/ml (range, 4 to 99 ng/ml), respectively. Maraviroc was detected in the plasma of mothers up to 48 h after dosing but only as long as 3.5 h in the infants. The median fetal-maternal area under the concentration-time curve (AUC) ratio was 0.009 (range, 0.000 to 0.015). Maraviroc receptor occupancy data showed evidence of unprotected CCR5 receptors on CD4(+) cells in the mothers 24 to 48 h after dosing. Extremely low CCR5 expression on CD4(+) cells of newborn macaques prevented determination of receptor occupancy in the infants. In rhesus macaques, maraviroc was poorly transferred across the placenta and was quickly cleared from the infants' blood. The low concentrations of fetal maraviroc and short pharmacokinetic profile in infants suggest that a single maternal intrapartum dose of maraviroc would not be effective in reducing the risk of MTCT of HIV.
View details for DOI 10.1128/AAC.00747-10
View details for Web of Science ID 000281907200002
View details for PubMedID 20696881
Impact of Interferon-Ribavirin Treatment on Hepatitis C Virus (HCV) Protease Quasispecies Diversity in HIV- and HCV-Coinfected Patients
JOURNAL OF INFECTIOUS DISEASES
2010; 202 (6): 889-893
Patients with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) coinfection for whom prior treatment of HCV with interferon-ribavirin has failed may require subsequent treatment with new HCV protease inhibitors (PIs). We evaluated the diversity of HCV nonstructural protein 3 (NS3) in 26 HCV- and HIV-coinfected patients receiving stable antiretroviral therapy (ART) who were treated with interferon-ribavirin. Plasma HCV RNA clonal analysis was performed. There was greater baseline NS3 diversity in patients with nonresponse or relapse than in those with sustained virologic response. Interferon-ribavirin treatment did not result in significant changes in HCV protease gene diversity or significant HCV PI resistance mutations. The effect of prior interferon-ribavirin treatment on HCV NS3 will likely not impact HCV PI efficacy in HIV-coinfected patients receiving ART.
View details for DOI 10.1086/655784
View details for Web of Science ID 000281091200010
View details for PubMedID 20677940
Effect of a Zoster Vaccine on Herpes Zoster-Related Interference with Functional Status and Health-Related Quality-of-Life Measures in Older Adults
JOURNAL OF THE AMERICAN GERIATRICS SOCIETY
2010; 58 (9): 1634-1641
To determine the efficacy of a zoster vaccine on herpes zoster (HR)-related interference with activities of daily living (ADLs) and health-related quality of life (HRQL).Randomized double-blind placebo controlled trial.Twenty-two U.S. sites.Thirty eight thousand five hundred forty-six women and men aged 60 and olcer.HZ burden of interference with ADLs and HRQL using ratings from the Zoster Brief Pain Inventory (ZBPI) and Medical Outcomes Study 12-item Short Form Survey (SF-12) mental component summary (MCS) and physical component summary (PCS) scores. Vaccine efficacy was calculated for the modified-intention-to-treat trial population and solely in participants who developed HZ.For the modified-intention-to-treat population, the overall zoster vaccine efficacy was 66% (95% confidence interval (CI)=55-74%) for ZBPI ADL burden of interference score and 55% (95% CI=48-61%) for both the SF-12 MCS and PCS scores. Of participants who developed HZ, zoster vaccine reduced the ZBPI ADL burden of interference score by 31% (95% CI=12-51%) and did not significantly reduce the effect on HRQL.Zoster vaccine reduced the burden of HZ-related interference with ADLs in the population of vaccinees and in vaccinees who developed HZ. Zoster vaccine reduced the effect of HZ on HRQL in the population of vaccinees but not in vaccinees who developed HZ.
View details for DOI 10.1111/j.1532-5415.2010.03021.x
View details for Web of Science ID 000281549000002
View details for PubMedID 20863322
Recent advances in hepatitis C virus treatment: review of HCV protease inhibitor clinical trials.
Reviews on recent clinical trials
2010; 5 (3): 158-173
Hepatitis C virus (HCV) infection affects millions of people world-wide, and chronic infection can result in end-stage liver disease and hepatocellular carcinoma. Conventional therapy to date has involved combination antiviral therapy including alpha-interferon and ribavirin; response rates with these drugs are variable based on both viral and host factors, such as HCV viral load, HCV genotype, HIV co-infection, host genetic polymorphisms (such as those in the IL28B region), and other factors. Recent advances in HCV treatment have included pegylated forms of alpha-interferon and, more recently, the development of specifically targeted antiviral therapy for HCV (STAT-C) with novel HCV protease inhibitors (PIs) for genotype 1 HCV. Although unlikely to be administered as monotherapy due to the potential for development of HCV PI drug resistance mutations, results of phase II trials of two PIs in development have recently been reported, demonstrating promising therapeutic efficacy of HCV PIs in combination with established conventional treatment. This review outlines the advances and the challenges in the development of these HCV PIs as effective HCV antiviral agents and their role in clinical practice.
View details for PubMedID 20482493
Is spinal tuberculosis contagious?
INTERNATIONAL JOURNAL OF INFECTIOUS DISEASES
2010; 14 (8): E659-E666
While pulmonary Mycobacterium tuberculosis infections are recognized for their public health implications, less is known about the infectiousness of extrapulmonary tuberculosis, specifically, spinal tuberculosis or Pott's disease. We present a case of spinal tuberculosis with concomitant active pulmonary tuberculosis in the absence of chest radiographic abnormalities or symptoms, and review the literature regarding infectiousness of concomitant spinal and pulmonary tuberculosis.
View details for DOI 10.1016/j.ijid.2009.11.009
View details for Web of Science ID 000282662100003
View details for PubMedID 20181507
Connection Domain Mutations in Treatment-Experienced Patients in the OPTIMA Trial
JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES
2010; 54 (2): 160-166
To determine the frequency of mutations in the connection domain (CD) of HIV reverse transcriptase in treatment-experienced patients in the Options in Management with Antiretrovirals trial, their impact on susceptibility to antiretroviral (ARV) drugs, and their impact on virologic outcomes.Baseline plasma ARV genotypes and inferred resistance phenotypes were obtained. Frequencies of E312Q, Y318F, G333D, G333E, G335C, G335D, N348I, A360I, A360V, V365I, A371V, A376S, and E399G were compared with a treatment-naive population. The association of CD mutations with inferred IC50 fold changes to nucleos(t)ide reverse transcriptase inhibitors was evaluated. Univariate and multivariate analyses examined the association of CD mutations with a >1 log10 per milliliter decrease in HIV viral load after 24 weeks on a new ARV regimen.Higher CD mutation rates were seen in Options in Management with Antiretrovirals patients (n = 345) compared with a treatment-naive population. CD mutations were associated with increased inferred IC50 fold changes to abacavir, stavudine, tenofovir, and zidovudine. On univariate analysis, A371V was associated with lack of virologic response, as was having any CD mutation on multivariate analysis.CD mutations are frequent in treatment-experienced populations. They are associated with reduced susceptibility to some nucleos(t)ide reverse transcriptase inhibitors and with a diminished response to ARV therapy.
View details for DOI 10.1097/QAI.0b013e3181cbd235
View details for Web of Science ID 000278100600008
View details for PubMedID 20130473
Impact of Highly Active Antiretroviral Therapy on Hepatitis C Virus Protease Quasispecies Diversity in HIV Co-Infected Patients
JOURNAL OF MEDICAL VIROLOGY
2010; 82 (5): 791-798
Many hepatitis C virus (HCV)-infected patients are also infected with HIV, and undergo antiretroviral (ARV) treatment for their human immunodeficiency virus (HIV) infection. Due to changes in HIV burden and immunologic status, HIV ARV treatment may have indirect effects on the HCV population, which could impact the effectiveness of subsequent HCV protease inhibitor (PI) treatment. The genetic variability of the protease-encoding HCV NS3 gene was evaluated in 10 co-infected patients initiating ARVs (both before and after ARV initiation), and compared to the genetic variability in 10 patients on stable ARV therapy. After RT-PCR of plasma-derived HCV RNA, a mean of 20 clones per patient time-point were sequenced and analyzed for changes in the HCV quasispecies population. No significant differences in sequence diversity or complexity at the nucleic acid or amino acid levels were seen at baseline between groups or between the two time points in either group. HCV protease diversity in the pre- and post-ARV treatment samples was not significantly different than samples from patients on stable ARV therapy. There was no significant development of amino acid substitutions known to confer HCV PI resistance in either group. Initiation of ARV for HIV infection does not significantly alter the genetic diversity or complexity of the HCV NS3 gene or result in increased number of HCV PI-associated amino acid changes. These results suggest ARV treatment for HIV would not affect the efficacy of HCV PI treatment.
View details for DOI 10.1002/jmv.21679
View details for Web of Science ID 000276324100009
View details for PubMedID 20336744
Effective Detection of the 2009 H1N1 Influenza Pandemic in US Veterans Affairs Medical Centers Using a National Electronic Biosurveillance System
2010; 5 (3)
The 2008-09 influenza season was the time in which the Department of Veterans Affairs (VA) utilized an electronic biosurveillance system for tracking and monitoring of influenza trends. The system, known as ESSENCE or Electronic Surveillance System for the Early Notification of Community-based Epidemics, was monitored for the influenza season as well as for a rise in influenza cases at the start of the H1N1 2009 influenza pandemic. We also describe trends noted in influenza-like illness (ILI) outpatient encounter data in VA medical centers during the 2008-09 influenza season, before and after the recognition of pandemic H1N1 2009 influenza virus.We determined prevalence of ILI coded visits using VA's ESSENCE for 2008-09 seasonal influenza (Sept. 28, 2008-April 25, 2009 corresponding to CDC 2008-2009 flu season weeks 40-16) and the early period of pandemic H1N1 2009 (April 26, 2009-July 31, 2009 corresponding to CDC 2008-2009 flu season weeks 17-30). Differences in diagnostic ICD-9-CM code frequencies were analyzed using Chi-square and odds ratios. There were 649,574 ILI encounters captured representing 633,893 patients. The prevalence of VA ILI visits mirrored the CDC's Outpatient ILI Surveillance Network (ILINet) data with peaks in late December, early February, and late April/early May, mirroring the ILINet data; however, the peaks seen in the VA were smaller. Of 31 ILI codes, 6 decreased and 11 increased significantly during the early period of pandemic H1N1 2009. The ILI codes that significantly increased were more likely to be symptom codes. Although influenza with respiratory manifestation (487.1) was the most common code used among 150 confirmed pandemic H1N1 2009 cases, overall it significantly decreased since the start of the pandemic.VA ESSENCE effectively detected and tracked changing ILI trends during pandemic H1N1 2009 and represents an important temporal alerting system for monitoring health events in VA facilities.
View details for DOI 10.1371/journal.pone.0009533
View details for Web of Science ID 000275197100015
View details for PubMedID 20209055
Structured interruptions of highly active antiretroviral therapy in cycles of 4 weeks off/12 weeks on therapy in children having a chronically undetectable viral load cause progressively smaller viral rebounds
INTERNATIONAL JOURNAL OF INFECTIOUS DISEASES
2010; 14 (1): E34-E40
To evaluate the viral, immune and clinical impact of a structured treatment interruption (STI) program of highly active antiretroviral therapy (HAART) in three cycles of 4 weeks off/12 weeks on therapy in a cohort of children with HIV infection under chronic viral control.Using a single-group time series experimentation design and following informed consent, the HAART of children with HIV and a chronically undetectable viral load (VL) was discontinued for 4 weeks and then restarted and continued for 12 weeks for a total of three cycles. The VL, CD4+/CD8+ lymphocytes, and clinical status were evaluated at the end of each STI and at 6 and 12 weeks after HAART was resumed.Four children with a median age of 10.3 years (range 6.5-11.2 years) were included in the study. Their clinical immune categories were: A1 (n=2), A2 (n=1), and B3 (n=1). Treatment of all four patients was with zidovudine (AZT)+lamivudine (3TC)+ritonavir (RTV). At the end of the first STI, VL was a median 214000 copies/ml (range 27400-616000), corresponding to 5.3 log(10) (range 4.4-5.8). At the end of the second STI, VL was a median 72400 copies/ml (range 17800-126000) or 4.7 log(10) (range 4.2-5.1), which corresponds to a rebound 0.6 log(10) lower than the first. At the end of the third STI, VL was a median 28200 copies/ml (range 5370-140000) or 4.45 log(10) (range 3.7-5.1), a rebound 0.85 log(10) lower than the first. All rebounds were followed by a decrease in the VL to undetectable levels during the treatment periods. CD8+ T lymphocyte counts increased during viral rebounds and an initial decrease in CD4+ T lymphocyte counts was followed by a tendency to increase even exceeding CD8+ T cell counts. Only one event of transitory severe immunosuppression occurred. There were no symptoms related to the HIV infection.The STI of HAART in cycles of 4 weeks off/12 weeks on therapy in children with chronically undetectable VL can cause progressively lower viral rebounds followed by a decrease to undetectable levels, with a low risk of severe immunosuppression and without the occurrence of symptoms related to HIV.
View details for DOI 10.1016/j.ijid.2009.03.003
View details for Web of Science ID 000273987200006
View details for PubMedID 19467895
Sudden sensorineural hearing loss associated with vardenafil.
2010; 30 (1): 112-?
The phosphodiesterase type 5 (PDE-5) inhibitors-sildenafil, vardenafil, and tadalafil-are used primarily in erectile dysfunction, but sildenafil is also indicated for pulmonary hypertension. Common adverse effects of vardenafil include headache, flushing, nasal congestion, dyspepsia, and nausea. Recently, PDE-5 inhibitors have been associated with adverse vision effects, and emerging evidence now indicates that they may also be responsible for hearing changes and hearing loss. We describe a patient who developed unilateral sudden sensorineural hearing loss possibly related to the use of vardenafil for erectile dysfunction. To our knowledge, only one other case of hearing loss related to this drug class has been published. Our patient was a 57-year-old man who came to the emergency department with right-sided mild-to-moderate hearing loss in the 500-3000-Hz range, confirmed by audiogram, that occurred after ingestion of vardenafil. The patient was hospitalized 2 days later for administration of intravenous dexamethasone, followed by oral prednisone. He reported that his hearing had improved on the fourth hospital day and was discharged 3 days later, continuing to taper the prednisone on an outpatient basis. A repeat audiogram after 10 days of corticosteroid therapy confirmed that his hearing in the 500-3000-Hz range was within normal limits. Use of the Naranjo adverse drug reaction probability scale indicated a possible (score of 3) adverse reaction of sudden sensorineural hearing loss associated with vardenafil consumption. We also performed an analysis of hearing loss cases related to PDE-5 inhibitors in the United States Food and Drug Administration's Adverse Event Reporting System database to compare the characteristics of our patient with those of other reported adverse event cases. Based on the temporal relation of the sudden sensorineural hearing loss to this patient's drug consumption, we propose that the vardenafil is a likely cause of the hearing loss. This case provides further evidence that PDE-5 inhibitor consumption should be considered as a possible cause in patients presenting with sudden sensorineural hearing loss.
View details for DOI 10.1592/phco.30.1.112
View details for PubMedID 20030481
Varicella-Zoster Virus-Specific Immune Responses to Herpes Zoster in Elderly Participants in a Trial of a Clinically Effective Zoster Vaccine
JOURNAL OF INFECTIOUS DISEASES
2009; 200 (7): 1068-1077
The objectives of this study were to evaluate the association between varicella-zoster virus (VZV)-specific humoral and cell-mediated immunity (CMI) to herpes zoster (HZ) and protection against HZ morbidity and to compare immune responses to HZ and zoster vaccine.In 981 elderly persons who developed HZ during a zoster vaccine efficacy trial (321 vaccinees and 660 placebo recipients) and 1362 without HZ (682 vaccinees and 680 placebo recipients), CMI was measured by VZV responder cell frequency and interferon-gamma enzyme-linked immunospot, and antibodies were measured by VZV enzyme-linked immunosorbent assay against affinity-purified VZV glycoproteins (gpELISA).Robust VZV CMI at HZ onset correlated with reduced HZ morbidity, whereas VZV gpELISA titers did not. Three weeks after HZ onset, gpELISA titers were highest in those with more severe HZ and were slightly increased in placebo recipients (compared with zoster vaccine recipients) and in older individuals. VZV CMI responses to HZ were similar in zoster vaccine and placebo recipients and were not affected by demographic characteristics or antiviral therapy, except for responder cell frequency at HZ onset, which decreased with age. When responses to zoster vaccine and HZ could be compared, VZV CMI values were similar, but antibody titers were lower.Higher VZV CMI at HZ onset was associated with reduced HZ severity and less postherpetic neuralgia. Higher antibody titers were associated with increased HZ severity and occurrence of postherpetic neuralgia. HZ and zoster vaccine generated comparable VZV CMI.
View details for DOI 10.1086/605611
View details for Web of Science ID 000269475000009
View details for PubMedID 19712037
The concurrent validity and responsiveness of the health utilities index (HUI 3) among patients with advanced HIV/AIDS
QUALITY OF LIFE RESEARCH
2009; 18 (7): 815-824
To assess the concurrent validity and responsiveness of the Health Utility Index 3 (HUI3) in patients with advanced HIV/AIDS, and to determine the responsiveness of this measure, the MOS-HIV and EQ-5D to HIV-related clinical events.Data from the OPTIMA (OPTions In Management with Antiretrovirals) trial was analyzed. Two aspects of the validity of the HUI3 were considered: concurrent validity was evaluated using Spearman correlations with MOS-HIV component and summary scores. Responsiveness to AIDS-defining events (ADE) and all adverse events (our external change criterion) was assessed using area under the receiver operating characteristic (AUROC) curves.The study enrolled 368 patients (mean follow-up: 3.66 years); 82% had at least one severe adverse event and 27% had at least one ADE. The HUI3 scale and items showed good concurrent validity, with 85% of the expected relationships with the MOS-HIV subscales verified. The HUI3 was responsive to both adverse events (AUROC [95%CI]: 0.68 [0.57, 0.80]) and ADEs (0.62 [0.51, 0.74]). The EQ-5D was responsive to ADEs (0.66 [0.56, 0.76]), but not responsive to adverse events (0.56 [0.46, 0.68]).The HUI3 is a valid and responsive measure of the change in HRQoL associated with clinical events in an advanced HIV/AIDS population.
View details for DOI 10.1007/s11136-009-9504-0
View details for Web of Science ID 000268881000003
View details for PubMedID 19562514
Quality of Life of Patients With Advanced HIV/AIDS: Measuring the Impact of Both AIDS-Defining Events and Non-AIDS Serious Adverse Events
JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES
2009; 51 (5): 631-639
To investigate the relative magnitude and duration of impact of AIDS-defining events (ADEs) and non-AIDS serious adverse events (SAEs) on health-related quality of life (HRQoL) among patients with advanced HIV/AIDS.We use data from OPTIMA (OPTions In Management with Antiretrovirals), a multinational, randomized, open, control, clinical management trial of treatment strategies for patients with multidrug-resistant HIV and advanced immune disease. Longitudinal models were used to determine the effects of ADEs and SAEs on HRQoL across periods before, during, and after event onset. The Medical Outcomes Study HIV Health Survey (MOS-HIV) physical and mental health summary scores (MOS-PHS and MOS-MHS), EQ-5D, and the Health Utilities Index Mark 3 HRQoL measures were all assessed at regular follow-up intervals during the trial.ADEs occurred much less frequently than SAEs (n = 147 vs. n = 821) in the study sample population of 368 patients, during median follow-up of 3.96 years. Although both ADEs and SAEs had significant negative impacts on HRQoL, SAEs had at least as large an impact upon HRQoL as ADEs when both were included in a multivariate linear regression model, controlling for other covariates. However, the effect of ADEs on HRQoL was more persistent, with larger magnitude of effect across all instruments in time intervals further from the onset of the event.Non-AIDS SAEs occurring in patients with late-stage HIV/AIDS seem to have at least as important an immediate impact on patient HRQoL as ADEs; however, the impact of ADEs seems to be more persistent. Our findings call for a greater emphasis on the detection and active prevention of non-AIDS SAEs in patients with late-stage HIV/AIDS.
View details for Web of Science ID 000268346600018
View details for PubMedID 19430303
Thrombocytopenia from Combination Treatment with Oseltamivir and Probenecid: Case Report, MedWatch Data Summary, and Review of the Literature
2009; 29 (8): 988-992
The possibility of an avian flu pandemic has spurred interest in preventive treatments with antivirals such as oseltamivir. Combining treatment with probenecid to delay excretion may extend limited supplies of oseltamivir. We previously conducted a pharmacokinetic study of oseltamivir plus probenecid among healthy volunteers. In this article, we describe a 68-year-old woman who, during the pharmacokinetic study, developed severe thrombocytopenia 2 weeks after starting oseltamivir plus probenecid. She was receiving no other drug therapy at the time. Her platelet count decreased from 200 to 15 x 10(3)/mm(3), although no clinically evident bleeding abnormalities were noted. The two drugs were discontinued. One week later, without any therapeutic intervention, her platelet count returned to normal. By using the Naranjo adverse drug reaction probability scale to assess the strength of the association between the drugs and the adverse event, a score of 7 was derived for both drugs, indicating that the association was probable. We found no previous literature reports of thrombocytopenia associated with either drug. However, a review of the United States Food and Drug Administration's Adverse Event Reporting System database found 93 cases of thrombocytopenia and/or decreased platelet counts associated with oseltamivir and 24 cases associated with probenecid administration. Signal detection analyses were significant for oseltamivir (p=0.001), but not probenecid. The underlying mechanism of thrombocytopenia with these drugs is unknown. Clinicians should be aware that the use of oseltamivir and probenecid has been reported to be associated with thrombocytopenia.
View details for Web of Science ID 000268563800012
View details for PubMedID 19637952
A Real-Time PCR Assay to Identify and Discriminate Among Wild-Type and Vaccine Strains of Varicella-Zoster Virus and Herpes Simplex Virus in Clinical Specimens, and Comparison With the Clinical Diagnoses
JOURNAL OF MEDICAL VIROLOGY
2009; 81 (7): 1310-1322
A real-time PCR assay was developed to identify varicella-zoster virus (VZV) and herpes simplex virus (HSV) DNA in clinical specimens from subjects with suspected herpes zoster (HZ; shingles). Three sets of primers and probes were used in separate PCR reactions to detect and discriminate among wild-type VZV (VZV-WT), Oka vaccine strain VZV (VZV-Oka), and HSV DNA, and the reaction for each virus DNA was multiplexed with primers and probe specific for the human beta-globin gene to assess specimen adequacy. Discrimination of all VZV-WT strains, including Japanese isolates and the Oka parent strain, from VZV-Oka was based upon a single nucleotide polymorphism at position 106262 in ORF 62, resulting in preferential amplification by the homologous primer pair. The assay was highly sensitive and specific for the target virus DNA, and no cross-reactions were detected with any other infectious agent. With the PCR assay as the gold standard, the sensitivity of virus culture was 53% for VZV and 77% for HSV. There was 92% agreement between the clinical diagnosis of HZ by the Clinical Evaluation Committee and the PCR assay results.
View details for DOI 10.1002/jmv.21506
View details for Web of Science ID 000266613900024
View details for PubMedID 19475609
Effect of the MTHFR C677T and A1298C Polymorphisms on Survival in Patients With Advanced CKD and ESRD: A Prospective Study
AMERICAN JOURNAL OF KIDNEY DISEASES
2009; 53 (5): 779-789
Abnormalities in the gene regulating methylenetetrahydrofolate reductase (MTHFR) are associated with increased homocysteine levels and increased mortality in normal and chronic kidney disease (CKD) populations.Gene association study.This was a substudy of 677 patients from 21 Veterans Affairs medical centers participating in a randomized clinical trial (Homocysteinemia in Kidney and End-Stage Renal Disease [HOST]) of the effect on all-cause mortality of vitamin-induced lowering of plasma homocysteine levels. Of 677 patients, 213 (31%) were treated by using dialysis (end-stage renal disease [ESRD]) and 464 (69%) had a Cockcroft-Gault estimated creatinine clearance less than 30 mL/min (advanced CKD).Polymorphisms C677T (rs1801133) and A1298C (rs1801131) of the MTHFR gene.Unadjusted and adjusted all-cause mortality.DNA was extracted from blood samples and amplified by means of polymerase chain reaction.The adjusted hazard ratio in a recessive model of the relationship between the C677T polymorphism and all-cause mortality in all patients was 1.47 (95% confidence interval, 1.00 to 2.16; P = 0.05). In patients with ESRD with the mutant TT genotype, the adjusted hazard ratio for mortality in all patients was 2.27 (95% confidence interval, 1.07 to 4.84; P = 0.03); patients with advanced CKD showed a similar, although not significant, trend. The risk of myocardial infarction (P = 0.05) and composite risk of myocardial infarction, stroke, lower-extremity amputation, and mortality (P = 0.02) were greater in patients with ESRD with the mutant T allele at nucleotide 677. The overall relationship between the A1298C polymorphism and mortality was not significant (P = 0.6).Participants were 98% men; DNA samples were not obtained at enrollment in HOST; linkage disequilibrium with another causal polymorphism is a potential confounding factor; and power was reduced by the limited number of participants.These findings provide additional support for the hypothesis that the mutant TT genotype at nucleotide 677 of the gene regulating MTHFR activity may increase the mortality risk in patients with ESRD.
View details for DOI 10.1053/j.ajkd.2008.12.023
View details for Web of Science ID 000265923500010
View details for PubMedID 19272686
Oseltamivir for treatment and prophylaxis of influenza infection
EXPERT OPINION ON DRUG SAFETY
2009; 8 (3): 357-371
Influenza infection is a global problem affecting millions of people worldwide, despite efficacious vaccines. Treatment and prophylaxis against influenza have been successful using antiviral medications such as adamantanes and neuraminidase inhibitors.To review the antiviral agents and specifically the neuraminidase inhibitor, oseltamivir, for use in treatment and prophylaxis of influenza infection.This review focuses on published literature regarding the clinical use of oseltamivir, as well as discussing emerging threats such as avian influenza, antiviral resistance, and strategies such as combination antiviral treatment to mitigate these threats.Oseltamivir is effective in reducing symptom burden in those with influenza A or B infection, and is preventative against developing infection after exposure. Emergence of naturally occurring or post-treatment oseltamivir-resistant influenza as well as an avian influenza pandemic may limit its future use as a monotherapeutic antiviral treatment agent.
View details for DOI 10.1517/14740330902840519
View details for Web of Science ID 000266768700011
View details for PubMedID 19355841
Dried-Plasma Transport Using a Novel Matrix and Collection System for Human Immunodeficiency Virus and Hepatitis C Virus Virologic Testing
JOURNAL OF CLINICAL MICROBIOLOGY
2009; 47 (5): 1491-1496
A novel method for the collection and transportation of dried-blood-plasma samples, SampleTanker (ST), was developed and compared to standard shipping protocols for frozen-plasma specimens containing human immunodeficiency virus type 1 (HIV-1) and/or hepatitis C virus (HCV). Matched frozen and dried 1-ml EDTA-containing plasma samples were collected and analyzed by several molecular-based virologic assays. After addition of 1.175 ml of reconstitution buffer, 1.035 ml of dried plasma was recovered. Mean intra-assay variances were 0.05, 0.05, and 0.06 log(10) copies/ml for the Versant, Amplicor, and NucliSens QT HIV-1 load assays, respectively (P, not significant). However, mean HIV-1 viral load was consistently reduced in dried samples by 0.32 to 0.51 log(10) copies/ml, depending on assay type (P < 0.05). Infectious HIV-1 was not recovered from dried ST plasma. There was no significant difference in HIV-1 viral load results obtained using ST after 8 weeks of storage at ambient temperature. Compared to frozen plasma, HIV-1 genotypic results were >99% concordant at the nucleotide and amino acid levels, as well as for resistance-associated mutations. We further demonstrated successful detection of multiple analytes, including HIV-1 viral load, HIV-1 antiretroviral resistance genotype, and HCV genotype, from a single ST unit. Dried plasma collected with ST yielded comparable results to frozen samples for multiple-analyte clinical testing. As such, ST could be a useful alternative for virologic tests and clinical trials worldwide by significantly diminishing transportation cost and the sample volume restrictions associated with dried-blood-spot technology.
View details for DOI 10.1128/JCM.02354-08
View details for Web of Science ID 000265641000031
View details for PubMedID 19321732
- Health-Related Quality of Life in a Randomized Trial of Antiretroviral Therapy for Advanced HIV Disease Journal of Acquired Immune Deficiency Syndromes 2009; 50 (1): 27-36
Health-Related Quality of Life in a Randomized Trial of Antiretroviral Therapy for Advanced HIV Disease
JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES
2009; 50 (1): 27-36
To assess and compare alternative approaches of measuring preference-based health-related quality of life (HRQoL) in treatment-experienced HIV patients and evaluate their association with health status and clinical variables.Cross-sectional study.Twenty-eight Veterans Affairs hospitals in the United States, 13 hospitals in Canada, and 8 hospitals in the United Kingdom.Three hundred sixty-eight treatment-experienced HIV-infected patients enrolled in the Options in Management with Antiretrovirals randomized trial.Baseline sociodemographic and clinical indicators and baseline HRQoL using the Medical Outcome Study HIV Health Survey (MOS-HIV), the EQ-5D, the EQ-5D visual analog scale (EQ-5D VAS), the Health Utilities Index Mark 3 (HUI3), and standard gamble (SG) and time trade-off (TTO) techniques.The mean (SD) baseline HRQoL scores were as follows: MOS-HIV physical health summary score 41.70 (11.16), MOS-HIV mental health summary score 44.76 (11.38), EQ-5D 0.77 (0.19), HUI3 0.59 (0.32), EQ-5D VAS 65.94 (21.71), SG 0.75 (0.29), and TTO 0.80 (0.31). Correlations between MOS-HIV summary scores and EQ-5D, EQ-5D VAS, and HUI3 ranged from 0.60 to 0.70; the correlation between EQ-5D and HUI3 was 0.73; and the correlation between SG and TTO was 0.43. Preference-based HRQoL scores were related to physical, mental, social, and overall health as measured by MOS-HIV. Concomitant medication use, CD4 cell count, and HIV viral load were related to some instruments' scores.On average, preference-based HRQoL for treatment-experienced HIV patients was decreased relative to national norms but also highly variable. Health status and clinical variables were related to HRQoL.
View details for Web of Science ID 000262019100004
View details for PubMedID 19295332
Infectious complications in OIF/OEF veterans with traumatic brain injury
JOURNAL OF REHABILITATION RESEARCH AND DEVELOPMENT
2009; 46 (6): 673-684
Of veterans from the U.S. Global War on Terrorism who have sought care in the Department of Veterans Affairs, approximately 12% have an infectious disease diagnosis. Infections in those veterans with traumatic brain injury (TBI) include infections associated with blast injuries and burns, such as skin and soft tissue infections; infections as a result of retained bullet or shrapnel fragments; pulmonary infections resulting from lung injury, intubation, or resultant tracheostomy; hospital-acquired infections, such as those associated with methicillin-resistant Staphylococcus aureus and other antimicrobial resistant organisms such as Acinetobacter baumannii; and infections from implanted prosthetic devices, such as metal hardware or skull flaps. Longer-term cognitive impairment may result in behaviors that place veterans with TBI at risk for human immunodeficiency virus or hepatitis C virus infections. Finally, chronic infections acquired abroad, such as cutaneous leishmaniasis or Q-fever, may be diagnosed after veterans return to the United States. These infections present challenges in terms of added morbidity and costs associated with complex antimicrobial management; isolation requirements; and surgical procedures, such as those to remove infected retained fragments or prosthetic devices. In this review, providers will become more familiar with the scope and complexity of infectious disease management in veterans with TBI.
View details for DOI 10.1682/JRRD.2008.09.0113
View details for Web of Science ID 000272638100005
View details for PubMedID 20104397
Novel Targets for Antiretroviral Therapy Clinical Progress to Date
2009; 69 (1): 31-50
The advent of HIV-1 resistance to antiretroviral medications, the need for lifelong antiretroviral therapy (ART) for HIV-infected individuals, and the goal of minimizing ART-related adverse effects and toxicity all drive the need for new antiretroviral drugs. Two new classes of antiretroviral medications for HIV treatment, the CCR5 and integrase inhibitors, have recently been approved for use in patients in whom previous HIV treatment regimens have failed. These new agent classes are a welcome addition to other antiretroviral classes, which include nucleoside reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitors and fusion inhibitors. Maraviroc is a CCR5 co-receptor antagonist that blocks HIV binding to the CCR5 receptor, which is a CD4 co-receptor necessary for cell entry. It is approved for use in ART-experienced patients with CCR5-tropic HIV, and was found to significantly reduce HIV viral load and increase CD4+ cell count when combined with an optimized background ART regimen (OBR). Treatment failure with maraviroc has been described and is primarily associated with the presence of CXCR4-tropic virus. Vicriviroc is another CCR5 co-receptor antagonist that is in late clinical trials. Raltegravir is the first US FDA-approved HIV-1 integrase inhibitor. It is approved for use in ART-experienced patients and was found to significantly reduce HIV viral load and increase CD4+ cell counts compared with placebo in combination with an OBR. Raltegravir has also been studied in treatment-naive patients and was found to be non-inferior to an efavirenz-based regimen. Elvitegravir is another HIV-1 integrase inhibitor in clinical development. Other new antiretroviral agents in clinical development include PRO140, a monoclonal antibody against CCR5, and bevirimat, a maturation inhibitor that prevents late-stage gag polyprotein processing. A number of other drug targets, such as CCR5 co-receptor agonists, CXCR4 co-receptor antagonists, novel fusion inhibitors, and alternative antiretroviral strategies, such as immune stimulation and gene therapy, are under investigation.
View details for Web of Science ID 000264204600003
View details for PubMedID 19192935
Pharmacokinetics and tolerability of oseltamivir combined with probenecid
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
2008; 52 (9): 3013-3021
Oseltamivir is an inhibitor of influenza virus neuraminidase, which is approved for use for the treatment and prophylaxis of influenza A and B virus infections. In the event of an influenza pandemic, oseltamivir supplies may be limited; thus, alternative dosing strategies for oseltamivir prophylaxis should be explored. Healthy volunteers were randomized to a three-arm, open-label study and given 75 mg oral oseltamivir every 24 h (group 1), 75 mg oseltamivir every 48 h (q48h) combined with 500 mg probenecid four times a day (group 2), or 75 mg oseltamivir q48h combined with 500 mg probenecid twice a day (group 3) for 15 days. Pharmacokinetic data, obtained by noncompartmental methods, and safety data are reported. Forty-eight subjects completed the pharmacokinetic analysis. The study drugs were generally well tolerated, except for one case of reversible grade 4 thrombocytopenia in a subject in group 2. The calculated 90% confidence intervals (CIs) for the geometric mean ratios between groups 2 and 3 and group 1 were outside the bioequivalence criteria boundary (0.80 to 1.25) at 0.63 to 0.89 for group 2 versus group 1 and 0.57 to 0.90 for group 3 versus group 1. The steady-state apparent oral clearance of oseltamivir carboxylate was significantly less in groups 2 (7.4 liters/h; 90% CI, 6.08 to 8.71) and 3 (7.19 liters/h; 90% CI, 6.41 to 7.98) than in group 1 (9.75 liters/h; 90% CI, 6.91 to 12.60) (P < 0.05 for both comparisons by analysis of variance). The (arithmetic) mean concentration at 48 h for group 2 was not significantly different from the mean concentration at 24 h for group 1 (42 +/- 76 and 81 +/- 54 ng/ml, respectively; P = 0.194), but the mean concentration at 48 h for group 3 was significantly less than the mean concentration at 24 h for group 1 (23 +/- 26 and 81 +/- 54 ng/ml, respectively; P = 0.012). Alternate-day dosing of oseltamivir plus dosing with probenecid four times daily achieved trough oseltamivir carboxylate concentrations adequate for neuraminidase inhibition in vitro, and this combination should be studied further.
View details for DOI 10.1128/AAC.00047-08
View details for Web of Science ID 000258667300003
View details for PubMedID 18559644
The Relationship Between HIV Infection and Cardiovascular Disease.
Current cardiology reviews
2008; 4 (3): 203-218
Over 30 million people are currently living with human immunodeficiency virus (HIV) infection, and over 2 million new infections occur per year. HIV has been found to directly affect vascular biology resulting in an increased risk of cardiovascular disease compared to uninfected persons. Although HIV infection can now be treated effectively with combination antiretroviral medications, significant toxicities such as hyperlipidemia, diabetes, and excess cardiovascular co-morbidity; as well as the potential for significant drug-drug interactions between HIV and cardiovascular medications, present new challenges for the management of persons infected with HIV. We first review basic principles of HIV pathogenesis and treatment and then discuss relevant clinical management strategies that will be useful for cardiologists who might be involved in the care of HIV infected patients.
View details for DOI 10.2174/157340308785160589
View details for PubMedID 19936197
Cost-effectiveness of HIV screening in patients older than 55 years of age
ANNALS OF INTERNAL MEDICINE
2008; 148 (12): 889-?
Although HIV infection is more prevalent in people younger than age 45 years, a substantial number of infections occur in older persons. Recent guidelines recommend HIV screening in patients age 13 to 64 years. The cost-effectiveness of HIV screening in patients age 55 to 75 years is uncertain.To examine the costs and benefits of HIV screening in patients age 55 to 75 years.Markov model.Derived from the literature.Patients age 55 to 75 years with unknown HIV status.Lifetime.Societal.HIV screening program for patients age 55 to 75 years compared with current practice.Life-years, quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness.For a 65-year-old patient, HIV screening using traditional counseling costs $55,440 per QALY compared with current practice when the prevalence of HIV was 0.5% and the patient did not have a sexual partner at risk. In sexually active patients, the incremental cost-effectiveness ratio was $30,020 per QALY. At a prevalence of 0.1%, HIV screening cost less than $60,000 per QALY for patients younger than age 75 years with a partner at risk if less costly streamlined counseling is used.Cost-effectiveness of HIV screening depended on HIV prevalence, age of the patient, counseling costs, and whether the patient was sexually active. Sensitivity analyses with other variables did not change the results substantially.The effects of age on the toxicity and efficacy of highly active antiretroviral therapy and death from AIDS were uncertain. Sensitivity analyses exploring these variables did not qualitatively affect the results.If the tested population has an HIV prevalence of 0.1% or greater, HIV screening in persons from age 55 to 75 years reaches conventional levels of cost-effectiveness when counseling is streamlined and if the screened patient has a partner at risk. Screening patients with advanced age for HIV is economically attractive in many circumstances.
View details for Web of Science ID 000257425000001
View details for PubMedID 18559840
Frequency of HIV screening in the Veterans Health Administration: Implications for early diagnosis of HIV infection
AIDS EDUCATION AND PREVENTION
2008; 20 (3): 258-264
We evaluated the frequency of HIV testing across the Department of Veterans Affairs (VA), the largest provider of HIV care in the United States. An electronic survey was used to determine the volume and location of HIV screening, confirmatory testing, rapid testing and laboratory consent policies in VA medical centers between October 1, 2005, and September 30, 2006. One hundred thirty-five VA laboratories reported that 112,033 HIV screening tests were performed (81% outpatients vs. 19% inpatients, p<.0001). Overall HIV prevalence was 1.49% (1.62% in inpatients vs. 1.46% in outpatients, p=N.S., range=0.2-3.8%). Rapid testing was available in 67% of facilities, 60% of which took place in the clinical laboratory. Sixty-four percent of labs required a copy of the informed consent in order to perform testing. We estimate that fewer than 10% of VA inpatients and fewer than 5% of VA outpatients were tested for HIV during the survey period. Substantial opportunities for increasing routine HIV testing exist in this population.
View details for Web of Science ID 000256717600005
View details for PubMedID 18558822
Varicella-zoster virus-specific immune responses in elderly recipients of a herpes zoster vaccine
JOURNAL OF INFECTIOUS DISEASES
2008; 197 (6): 825-835
A double-blind, placebo-controlled trial that involved 38,546 subjects > or =60 years old demonstrated efficacy of a high-potency live-attenuated Oka/Merck varicella-zoster virus (VZV) vaccine. The trial included an immunology substudy to determine the relationship of VZV-specific immune responses to vaccination and clinical outcome.The immunology substudy enrolled 1395 subjects at 2 sites where blood samples obtained prior to vaccination, at 6 weeks after vaccination, and at 1, 2, and 3 years thereafter were tested for VZV-specific cell-mediated immunity (VZV-CMI) by gamma-interferon ELISPOT and responder cell frequency assays and for VZV antibody by glycoprotein ELISA.VZV-CMI and VZV antibodies were significantly increased in vaccine recipients at 6 weeks after vaccination. The vaccine-induced increases in VZV-CMI persisted during the 3 years of follow-up, although their magnitude decreased over time. The magnitude of these VZV-specific immune responses was greater in subjects 60-69 years old than in subjects > or =70 years old.The zoster vaccine induced a significant increase in VZV-CMI and VZV antibody. The magnitude and duration of the boost in VZV-CMI in vaccine recipients and the relationship of this boost to age paralleled the clinical effects of the vaccine observed during the efficacy trial. These findings support the hypothesis that boosting VZV-CMI protects older adults against herpes zoster and postherpetic neuralgia.
View details for DOI 10.1086/528696
View details for Web of Science ID 000253773900008
View details for PubMedID 18419349
Safety, tolerability, pharmacokinetics, and efficacy of an interleukin-2 agonist among HIV-infected patients receiving highly active antiretroviral therapy
JOURNAL OF INTERFERON AND CYTOKINE RESEARCH
2008; 28 (2): 89-100
We sought to determine the safety, maximum tolerated dose, optimal dose, and preliminary dose efficacy of intermittent subcutaneously (s.c.) administered BAY 50-4798 among patients with HIV infection receiving highly active antiretroviral therapy (HAART) compared with patients receiving HAART alone. A phase I/II randomized, double-blind, dose-escalation study was conducted of the safety, tolerability, pharmacokinetics, and efficacy of s.c. BAY 50-4798 administered to HIV-infected patients already receiving stable HAART. There were no unexpected safety findings in a population of HIV-infected patients receiving HAART plus SC BAY 50-4798 as adjunctive therapy. BAY 50-4798 exhibited nearly dose-proportional pharmacokinetics, and accumulation was minimal during multiple-dose treatment. Limited efficacy data indicated that treatment with BAY 50-4798 caused at least a transient increase in CD4(+) T cell counts in some recipients, particularly at the early time points. In general, this effect appeared to increase with increasing dose. Bay 50-4798 was generally well tolerated across the dose range tested, but a lack of potent, sustained immunologic activity suggests that further optimization of dose and schedule will be necessary.
View details for DOI 10.1089/jir.2007.0064
View details for Web of Science ID 000253629900004
View details for PubMedID 18279104
Severe pneumonia due to adenovirus serotype 14: A new respiratory threat?
CLINICAL INFECTIOUS DISEASES
2008; 46 (3): 421-425
Adenoviruses are associated with sporadic infection and community and institutional outbreaks; they can cause especially severe disease in infants, young children, immunocompromised persons, and transplant recipients. Fifty-two adenovirus serotypes have been recognized and classified within 7 subgroups or species (A-G), with limited data available on associated clinical syndromes and disease severity in more than one-half of the known serotypes.We describe the clinical presentation and virologic characterization of 1 adult and 2 pediatric patients admitted to 2 separate hospitals during April-May 2006 with severe acute respiratory tract infection. All patients had underlying chronic pulmonary disease; none were severely immunocompromised. All 3 experienced serious chronic sequelae or died.Adenovirus was isolated from all 3 case patients. Adenovirus serotype 14, a subspecies B2 serotype not previously associated with severe clinical illness, was confirmed by neutralization assay and sequencing of the hexon gene. Restriction enzyme analysis with BamHI, BglII, HindIII, and SmaI showed all 3 viruses to be identical and to belong to a new genome type that we have designated "Ad14a."Our identification of severe respiratory illness due to a previously rarely reported adenovirus serotype may signify the emergence in the United States of a new genomic variant that has the potential to spread globally and cause epidemics. These case reports highlight the need for rapid diagnosis and improved surveillance, with serotyping and molecular characterization, to identify emerging variants of adenovirus, which may assist with targeted development of antiviral agents or type-specific vaccines.
View details for DOI 10.1086/525261
View details for Web of Science ID 000252221200010
View details for PubMedID 18173356
- HIV infection in the elderly Clinical Interventions in Aging 2008; 3 (4): 1-20
Prevalence of HIV infection among inpatients and outpatients in department of veterans affairs health care systems: Implications for screening programs for HIV
AMERICAN JOURNAL OF PUBLIC HEALTH
2007; 97 (12): 2173-2178
We sought to determine the prevalence of HIV in both inpatient and outpatient settings in 6 Department of Veterans Affairs (VA) health care sites.We collected demographic data and data on comorbid conditions and then conducted blinded, anonymous HIV testing. We conducted a multivariate analysis to determine predictors of HIV infection.We tested 4500 outpatient blood specimens and 4205 inpatient blood specimens; 326 (3.7%) patients tested positive for HIV. Inpatient HIV prevalence ranged from 1.2% to 6.9%; outpatient HIV prevalence ranged from 0.9% to 8.9%. Having a history of hepatitis B or C infection, a sexually transmitted disease, or pneumonia also predicted HIV infection. The prevalence of previously undocumented HIV infection varied from 0.1% to 2.8% among outpatients and from 0.0% to 1.7% among inpatients.The prevalence of undocumented HIV infection was sufficiently high for routine voluntary screening to be cost effective in each of the 6 sites we evaluated. Many VA health care systems should consider expanded routine voluntary HIV screening.
View details for DOI 10.2105/AJPH.2007.110700
View details for Web of Science ID 000251395900022
View details for PubMedID 17971545
A systematic review of cost-utility analyses in HIV/AIDS: Implications for public policy
MEDICAL DECISION MAKING
2007; 27 (6): 789-821
To determine whether gaps exist in published cost-utility analyses as measured by their coverage of topics addressed in current HIV guidelines from the Department of Health and Human Services (DHHS).A systematic review of US-based cost-effectiveness analyses of HIV/AIDS prevention and management strategies, based on original, published research.Predefined criteria were used to identify all analyses pertaining to prevention and management of HIV/AIDS; information was collected on type of strategy, patient demographics, study perspective, quality of the study, effectiveness measures, costs, and cost-effectiveness ratios.One hundred and six studies were identified; 62 described strategies for averting new HIV infections, and 44 dealt with managing persons who are HIV positive. The quality of studies was generally high, but gaps were found in all studies. Especially common were omissions in reporting data abstraction methodology and discussions of direction and magnitude of potential biases. Among the 22 most highly rated papers (score of 90 or higher), only 1 was cited in the guidelines, and 3 papers reported on interventions that were superseded by newer approaches. Using a USD 100,000 threshold, the guidelines usually endorsed interventions found to be cost-effective. Exceptions included recommending postexposure prophylaxis (PEP) for populations in which PEP is unlikely to be cost-effective and not recommending primary resistance testing in treatment-naive persons, although the intervention was reported to have a cost-effectiveness ratio of less than USD 50,000.Despite an abundant literature on the cost-utility of HIV/AIDS-targeted strategies, guidelines cite relatively few of these papers, and gaps exist regarding assessments of some strategies and special populations.
View details for DOI 10.1177/0272989X07306112
View details for Web of Science ID 000251318600008
View details for PubMedID 18057191
Evolution of genotypic resistance algorithms and their impact on the interpretation of clinical trials: An OPTIMA trial substudy
HIV CLINICAL TRIALS
2007; 8 (5): 293-302
The outdated rules of older HIV genotypic resistance algorithms can affect virologic responses. This study was designed to determine how often these incorrect resistance interpretations affect analyses of long-term clinical trials, antiretroviral (ARV) choices, and HIV disease progression rates.Baseline VIRCO virtual phenotypes (VVP) from patients screened in 2001-2002 for OPTIMA were compared to 2005 Stanford HIV resistance database algorithm (HIVDB-10/05, version 4.1.4) interpretations of the HIV-1 pol sequences. Drugs were called discordant if resistant by one algorithm and sensitive by the other.Of 2,341 drug comparisons, 501 (21.4%) were discordant, affecting 140 (86.4%) of 162 screened patients. NRTI/NtRTIs were more discordant than NNRTIs and PIs (38.6% vs. 4.3% vs. 12.8%; p < .0001). Sixty-nine (53%) patients were placed on 2 drugs reported as sensitive by VVP but resistant by HIVDB-10/05; they had higher than expected rates of disease progression and a similar time to first event or death as patients on ARVs classified as resistant by both algorithms (p = .61).Underestimation of drug resistance by older genotypic algorithms resulted in using ARVs incorrectly thought to be sensitive and in higher than expected rates of HIV disease progression. The use of older genotypes to interpret long-term clinical trials should account for this underestimation, because results may be different if viral sequences are interpreted with newer algorithms.
View details for DOI 10.1310/hct0805-293
View details for Web of Science ID 000250560300004
View details for PubMedID 17956830
HIV testing of at risk patients in a large integrated health care system
JOURNAL OF GENERAL INTERNAL MEDICINE
2007; 22 (3): 315-320
Early identification of HIV infection is critical for patients to receive life-prolonging treatment and risk-reduction counseling. Understanding HIV screening practices and barriers to HIV testing is an important prelude to designing successful HIV screening programs. Our objective was to evaluate current practice patterns for identification of HIV.We used a retrospective cohort analysis of 13,991 at-risk patients seen at 4 large Department of Veterans Affairs (VA) health-care systems. We also reviewed 1,100 medical records of tested patients. We assessed HIV testing rates among at-risk patients, the rationale for HIV testing, and predictors of HIV testing and of HIV infection.Of the 13,991 patients at risk for HIV, only 36% had been HIV-tested. The prevalence of HIV ranged from 1% to 20% among tested patients at the 4 sites. Approximately 90% of patients who were tested had a documented reason for testing.One-half to two-thirds of patients at risk for HIV had not been tested within our selected VA sites. Among tested patients, the rationale for HIV testing was well documented. Further testing of at-risk patients could clearly benefit patients who have unidentified HIV infection by providing earlier access to life-prolonging therapy.
View details for DOI 10.1007/s11606-006-0028-9
View details for Web of Science ID 000244718600005
View details for PubMedID 17356961
- Role of Environmental Surveillance in Dtermining the Risk of Hospital-Acquired Legionellosis: A National Surveillance Study With Clinical Correlations Infection Control and Hospital Epidemiology 2007; 28 (7): 818-824
- Representational Fluency in HIV Clinical Practice: A Model of Instructor Discourse Journal of Continuing Education in the Health Professions 2007; 27 (3): 149-156
- Darunavir in the treatment of HIV-1 infection - Viewpoint DRUGS 2007; 67 (18): 2803-2803
- siRNA delivery into human T cells and primary cells with carbon-nanotube transporters ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 2007; 46 (12): 2023-2027
Relationship between antiretroviral prescribing patterns and treatment guidelines in treatment-naive HIV-1-infected US veterans (1992-2004)
JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES
2007; 44 (1): 20-29
To analyze temporal patterns of antiretroviral (ARV) prescribing practices relative to nationally defined guidelines in treatment-naive patients with HIV-1 infection.Retrospective cohort study.We evaluated ARV prescribing patterns among ARV treatment-naive veterans who were receiving care within the US Department of Veterans Affairs (VA) from 1992 through 2004 in comparison to evolving adult HIV-1 treatment guidelines.A total of 15,934 patients initiated ARV treatment. Since 1999, >94% of patients initiated at least a 3-ARV medication combination, although the percentage of patients who initiated a guideline "preferred" or "alternative" regimen never rose to greater than 72% and was significantly associated with being black and with region of care. After 1999, 20% of patients started 4 or more active ARV agents in combination, which was significantly associated with lower baseline CD4 cell count, higher viral load, and receiving care in the western United States. The proportion of patients receiving guideline "not recommended" regimens (virologically undesirable or overlapping toxicities) was <1% after 1997. VA prescribing trends generally predated guideline recommendations by 6 to 12 months.VA prescribing patterns for ARV initiation adhere to treatment guidelines that maximize safety. Guidelines designed to maximize efficacy were not followed as stringently. Evaluating clinical practice patterns against contemporary treatment guidelines can inform guideline development.
View details for Web of Science ID 000243189400004
View details for PubMedID 17091020
HIV-1 load quantitation: A 17-year perspective
JOURNAL OF INFECTIOUS DISEASES
2006; 194: S38-S44
During the past decade and a half, quantitation of plasma-associated human immunodeficiency virus type 1 (HIV-1) RNA level, or HIV-1 load, has been validated in clinical practice and clinical trials as an important surrogate marker of HIV-1 disease progression and of the potency and durability of antiretroviral regimens. This review highlights some of the history, accomplishments, and impact of Tom Merigan's laboratory on the use of HIV-1 load as a marker, as well as on updating technologies for determining HIV-1 load, their performance, interpretation of the results, and their use in clinical practice.
View details for Web of Science ID 000240317800007
View details for PubMedID 16921471
Prevention of shingles by varicella zoster virus vaccination
EXPERT REVIEW OF VACCINES
2006; 5 (4): 431-443
Herpes zoster is caused by reactivation from previous varicella zoster virus (VZV) infection, and affects millions of people worldwide. It primarily affects older adults and those with immune system dysfunction, most likely as a result of reduced or lost VZV-specific cell-mediated immunity. Complications include post-herpetic neuralgia, a potentially debilitating and chronic pain syndrome. Current treatment of herpes zoster and post-herpetic neuralgia involves antiviral agents and analgesics, and is associated with significant economic cost. Results from several clinical trials have determined that a live, attenuated VZV vaccine using the Oka/Merck strain (Zostavax) is safe, elevates VZV-specific cell-mediated immunity, and significantly reduces the incidence of herpes zoster and post-herpetic neuralgia in people over 60 years of age. Regulatory approval has recently been obtained and once launched, it is expected that this vaccine will significantly reduce the morbidity and financial costs associated with herpes zoster. Durability of vaccine response and possible booster vaccination will still need to be determined.
View details for DOI 10.1586/14760518.104.22.1681
View details for Web of Science ID 000243482800012
View details for PubMedID 16989624
Hepatitis C virus protease gene diversity in patients coinfected with human immunodeficiency virus
JOURNAL OF VIROLOGY
2006; 80 (8): 4196-4199
The clonal variability of the hepatitis C virus (HCV) protease gene in 24 individuals with HCV genotypes 1a, 1b, 2b, and 3a who were coinfected with the human immunodeficiency virus was evaluated. Within-genotype variability at the nucleotide and amino acid levels ranged from 6.5 to 8.6% and 2.2 to 3.8%, respectively. After adjustments were made for correlation of intrapatient clonal variation, mixed-model analysis indicated that nucleotide and amino acid variability among patients with different genotypes did not differ significantly. However, within individual patients, clonal variability differed by up to 5.3% and 5.8% at the nucleotide and amino acid levels, respectively, and genotype 1a had significantly greater nucleotide variability than other genotypes (P = 0.01). Significant variability exists within HCV protease gene variants at the patient level and could affect the effectiveness of HCV protease inhibitors.
View details for DOI 10.1128/JVI.80.8.4196-4199.2006
View details for Web of Science ID 000236685600053
View details for PubMedID 16571838
The effect of diagnosis with HIV infection on health-related quality of life
QUALITY OF LIFE RESEARCH
2006; 15 (1): 69-82
We sought to understand how diagnosis with HIV affects health-related quality of life. We assessed health-related quality of life using utility-based measures in a Department of Veterans Affairs (VA) clinic and a University-based clinic. Respondents assessed health-related quality of life regarding their current health, and retrospectively assessed their health 1 month prior to and 2 months after diagnosis with HIV infection. Sixty-six patients completed the study. The overall mean utilities for health 1 month before and 2 months after diagnosis were 0.87 (standard error 0.037), and 0.80 (0.043) (p<0.005 by rank sign test), but the effect of diagnosis differed between the two clinics, with a substantial decrease in the university clinic and a small non-significant decrease in the VA clinic. The overall mean utility for current health was 0.85 (0.034), assessed on average 7.5 years after diagnosis. When asked directly whether diagnosis of HIV decreased health-related quality of life, 47% agreed, but 35% stated that HIV diagnosis positively affected health-related quality of life. Diagnosis with HIV decreased health-related quality of life at 2 months on average, but this effect diminished over time, and differed among patient populations. Years after diagnosis, although half of the patients believed that diagnosis reduced health-related quality of life, one-third reported improved health-related quality of life.
View details for DOI 10.1007/s11136-005-8485-x
View details for Web of Science ID 000234601400007
View details for PubMedID 16411032
Case files from Stanford University Medical Center: the initial presentation of HIV-1 infection--where public and personal health meet.
MedGenMed : Medscape general medicine
2006; 8 (1): 24-?
View details for PubMedID 16915154
- The safety and tolerability of Z-100 in patients infected with HIV-1 Antiviral Therapy 2006; 11: 297-303
Utilization and access to Antiretroviral genotypic resistance testing and results within the US department of veterans affairs
JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES
2006; 41 (1): 59-62
We sought to characterize variation in the use of HIV genotypic resistance tests and how results were reported.Clinicians and laboratory managers at all Veterans Affairs (VA) medical centers were asked to complete a survey in March 2003 regarding HIV resistance testing practices.Surveys from 131 of 150 sites were returned. Forty-eight percent of HIV clinicians indicated that US Department of Health and Human Services guidelines were the usual basis for ordering tests. Although between 12% and 31% of respondents indicated that they always, sometimes, seldom, or never ordered resistance tests in patients with acute or chronic HIV infection, >70% ordered tests in adherent patients with treatment failure. Among the 32 centers with >200 patients in care, 13 +/- 8 (mean +/- standard deviation) tests were performed per 100 patients in care during 2002. Forty-nine percent of clinicians said that tests were helpful, but only 33% expressed confidence in using test results. Only 40% of sites entered results in the VA electronic medical record.Ordering patterns for HIV resistance tests differed significantly among VA sites. A minority of clinicians indicated confidence in the use of test results. A consistent system to capture and present complete results was absent.
View details for Web of Science ID 000234438500009
View details for PubMedID 16340474
Accuracy, precision, and consistency of expert HIV type 1 genotype interpretation: An international comparison (The GUESS Study)
CLINICAL INFECTIOUS DISEASES
2005; 41 (1): 92-99
Resistance testing is considered standard of care in HIV medicine, but there is no standard interpretation system for genotype tests. We sought to determine how much agreement exists within a group of experts in the interpretation of complex genotypes.Genotypes from clinical specimens were sent to an international panel of 12 resistance experts. Phenotypic susceptibility testing of these clinical isolates was performed with antivirogram. Experts predicted phenotype fold change category (<2.5-fold change, 2.5-4.0-fold change, >4.0- to 7.0-fold change, >7.0- to 10-fold change, >10- to 20-fold change, or >20-fold change) and predicted expected drug activity for each of 16 antiretroviral drugs. Experts were also asked to make treatment recommendations on the basis of the genotype.The experts predicted the exact phenotype fold change category correctly 44% of the time, but they varied widely by antiretroviral drug (range, 25%-74%). The highest accuracy was observed for lamivudine (74%) and the nonnucleoside reverse transcriptase inhibitors (66%-69%). Experts generally predicted higher levels of resistance to the remaining nucleoside reverse transcriptase inhibitors than what was found by phenotypic testing. Agreement among experts in predicting phenotype fold change category ranged widely depending on the drug (median agreement, 42% [range, 28%-74%]); the same pattern was observed in predicting expected drug activity (median agreement, 45% [range, 32%-87%]). Experts agreed on treatment recommendations in a median of 79% of instances, and recommendations were consistent over time, with blinded retesting.Although their ability to predict phenotype from a genotype varied for individual antiretroviral drugs, this expert panel had a high degree of agreement in deriving treatment recommendations from the genotype.
View details for Web of Science ID 000229530400015
View details for PubMedID 15937768
A vaccine to prevent herpes zoster and postherpetic neuralgia in older adults
NEW ENGLAND JOURNAL OF MEDICINE
2005; 352 (22): 2271-2284
The incidence and severity of herpes zoster and postherpetic neuralgia increase with age in association with a progressive decline in cell-mediated immunity to varicella-zoster virus (VZV). We tested the hypothesis that vaccination against VZV would decrease the incidence, severity, or both of herpes zoster and postherpetic neuralgia among older adults.We enrolled 38,546 adults 60 years of age or older in a randomized, double-blind, placebo-controlled trial of an investigational live attenuated Oka/Merck VZV vaccine ("zoster vaccine"). Herpes zoster was diagnosed according to clinical and laboratory criteria. The pain and discomfort associated with herpes zoster were measured repeatedly for six months. The primary end point was the burden of illness due to herpes zoster, a measure affected by the incidence, severity, and duration of the associated pain and discomfort. The secondary end point was the incidence of postherpetic neuralgia.More than 95 percent of the subjects continued in the study to its completion, with a median of 3.12 years of surveillance for herpes zoster. A total of 957 confirmed cases of herpes zoster (315 among vaccine recipients and 642 among placebo recipients) and 107 cases of postherpetic neuralgia (27 among vaccine recipients and 80 among placebo recipients) were included in the efficacy analysis. The use of the zoster vaccine reduced the burden of illness due to herpes zoster by 61.1 percent (P<0.001), reduced the incidence of postherpetic neuralgia by 66.5 percent (P<0.001), and reduced the incidence of herpes zoster by 51.3 percent (P<0.001). Reactions at the injection site were more frequent among vaccine recipients but were generally mild.The zoster vaccine markedly reduced morbidity from herpes zoster and postherpetic neuralgia among older adults.
View details for Web of Science ID 000229446400004
View details for PubMedID 15930418
Proteomic analysis of serum cytokine levels in response to highly active antiretroviral therapy (HAART)
JOURNAL OF PROTEOME RESEARCH
2005; 4 (2): 227-231
A 30-cytokine protein microarray was used to screen for cytokine profile changes in HIV-infected patients in response to highly active antiretroviral therapy (HAART). Serum cytokines showing significant changes were confirmed by enzyme immunoassay. Monokine induced by gamma-interferon (MIG) and interferon-inducible protein-10 (IP-10) levels significantly decreased after 24 weeks of HAART. Protein microarrays are useful for initial screening of novel cytokine expression. Further studies are needed to elucidate the role of MIG and IP-10 in response to HAART.
View details for DOI 10.1021/pr049930y
View details for Web of Science ID 000228421900004
View details for PubMedID 15822897
Cost-effectiveness of screening for HIV in the era of highly active antiretroviral therapy
NEW ENGLAND JOURNAL OF MEDICINE
2005; 352 (6): 570-585
The costs, benefits, and cost-effectiveness of screening for human immunodeficiency virus (HIV) in health care settings during the era of highly active antiretroviral therapy (HAART) have not been determined.We developed a Markov model of costs, quality of life, and survival associated with an HIV-screening program as compared with current practice. In both strategies, symptomatic patients were identified through symptom-based case finding. Identified patients started treatment when their CD4 count dropped to 350 cells per cubic millimeter. Disease progression was defined on the basis of CD4 levels and viral load. The likelihood of sexual transmission was based on viral load, knowledge of HIV status, and efficacy of counseling.Given a 1 percent prevalence of unidentified HIV infection, screening increased life expectancy by 5.48 days, or 4.70 quality-adjusted days, at an estimated cost of 194 dollars per screened patient, for a cost-effectiveness ratio of 15,078 dollars per quality-adjusted life-year. Screening cost less than 50,000 dollars per quality-adjusted life-year if the prevalence of unidentified HIV infection exceeded 0.05 percent. Excluding HIV transmission, the cost-effectiveness of screening was 41,736 dollars per quality-adjusted life-year. Screening every five years, as compared with a one-time screening program, cost 57,138 dollars per quality-adjusted life-year, but was more attractive in settings with a high incidence of infection. Our results were sensitive to the efficacy of behavior modification, the benefit of early identification and therapy, and the prevalence and incidence of HIV infection.The cost-effectiveness of routine HIV screening in health care settings, even in relatively low-prevalence populations, is similar to that of commonly accepted interventions, and such programs should be expanded.
View details for Web of Science ID 000226862100007
View details for PubMedID 15703422
- Clinical utility of viral load measurements in individuals with chronic hepatitis C infection on antiviral therapy. Journal of Viral Hepatitis 2005; 12 (5): 465-472
- Cost-effectiveness of screening for HIV in the era of highly active antiretroviral therapy New England Journal of Medicine 2005; 352 (6): 570-585
Prevalence of antiretroviral drug resistance in the HIV-1-infected urban indigent population in San Francisco: a representative study
INTERNATIONAL JOURNAL OF STD & AIDS
2004; 15 (8): 543-551
We determined the prevalence of antiretroviral (ARV) resistance in HIV-1 infected indigent persons in San Francisco, California. Three hundred and twenty-seven subjects (159 (49%) ARV naïve, and 168 (51%) ARV-experienced), were recruited during 1996-97 and 1999-2000. Plasma HIV-1 viral load quantification and genotypic resistance testing were performed. Twice as many subjects received nucleoside reverse transcriptase inhibitors (NRTIs) as non-nucleoside reverse transcriptase inhibitors (NNRTIs) or protease inhibitors (PIs); resistance mutation prevalences were 30%, 14% and 16% respectively. Risk of any resistance mutations was strongly and independently associated with prior ARV exposure (OR = 1.3 per year of exposure, P < 0.0001) and with ARV exposure prior to HAART (OR = 2.5, P = 0.015). Prevalences of primary ARV resistance mutations among both treatment-naive and treatment-experienced subjects in this indigent urban population are low compared to other observational cohorts, are directly related to length and type of prior ARV exposure, and did not increase significantly between recruitment periods.
View details for Web of Science ID 000223453900010
View details for PubMedID 15307966
Multicenter evaluation of the performance characteristics of the Bayer VERSANT HCV RNA 3.0 assay (bDNA)
JOURNAL OF CLINICAL MICROBIOLOGY
2004; 42 (2): 563-569
In this multicenter evaluation, the VERSANT HCV RNA 3.0 Assay (bDNA) (Bayer Diagnostics, Tarrytown, N.Y.) was shown to have excellent reproducibility, linearity, and analytical sensitivity across specimen collection matrices (serum, EDTA, ACD-A), and hepatitis C virus (HCV) genotypes 1 to 6. The VERSANT HCV bDNA Assay has a reportable range of 615 to 7690000 (7.69 x 10(6)) IU/ml. The total coefficient of variation (CV) ranged from 32.4% at 615 IU/ml to 17% at 6.8 x 10(6) IU/ml. The assay was linear across the reportable range. Analytical specificity of 98.8% was determined by testing 999 specimens from volunteer blood donors. Evaluation of HCV genotypes using RNA transcripts of representative clones of 1a, 1b, 2a, 2b, 2c, 3a, 4a, 5a, and 6a and patient specimens showed that the largest difference between genotype 1, upon which the assay is standardized, and non-1 genotypes was within 1.5-fold. Testing of potentially interfering endogenous substances and exogenous substances and conditions found no interference in HCV-positive or HCV-negative specimens except for unconjugated bilirubin at concentrations of >or=20 mg/dl and protein at concentrations of >or=9 g/dl. Biological variability was estimated from 29 clinically stable individuals not on HCV therapy who were tested weekly over an 8-week period. The combined estimate of total (biologic plus assay) variability was 0.15 log(10) standard deviation (CV, 36.1%), a fold change of 2.6. Thus, the observed fold change between any two consecutive HCV RNA measures is expected to be less than 2.6-fold (equivalent to 0.41 log(10) IU/ml) 95% of the time in clinically stable individuals.
View details for DOI 10.1128/JCM.42.2.563-569.2004
View details for Web of Science ID 000189379000012
View details for PubMedID 14766817
Inhibition of HIV infectivity by a natural human isolate of Lactobacillus jensenii engineered to express functional two-domain CD4
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2003; 100 (20): 11672-11677
The predominant mode of HIV transmission worldwide is via heterosexual contact, with the cervico-vaginal mucosa being the main portal of entry in women. The cervico-vaginal mucosa is naturally colonized with commensal bacteria, primarily lactobacilli. To address the urgent need for female-controlled approaches to block the heterosexual transmission of HIV, we have engineered natural human vaginal isolates of Lactobacillus jensenii to secrete two-domain CD4 (2D CD4) proteins. The secreted 2D CD4 recognized a conformation-dependent anti-CD4 antibody and bound HIV type 1 (HIV-1) gp120, suggesting that the expressed proteins adopted a native conformation. Single-cycle infection assays using HIV-1HxB2 carrying a luciferase reporter gene demonstrated that Lactobacillus-derived 2D CD4 inhibited HIV-1 entry into target cells in a dose-dependent manner. Importantly, coincubation of the engineered bacteria with recombinant HIV-1HxB2 reporter virus led to a significant decrease in virus infectivity of HeLa cells expressing CD4-CXCR4-CCR5. Engineered lactobacilli also caused a modest, but statistically significant, decrease in infectivity of a primary isolate, HIV-1JR-FL. This represents an important first step toward the development of engineered commensal bacteria within the vaginal microflora to inhibit heterosexual transmission of HIV.
View details for DOI 10.1073/pnas.1934747100
View details for Web of Science ID 000185685700089
View details for PubMedID 12972635
High levels of adherence do not prevent accumulation of HIV drug resistance mutations
2003; 17 (13): 1925-1932
To assess the relationship between development of antiretroviral drug resistance and adherence by measured treatment duration, virologic suppression, and the rate of accumulating new drug resistance mutations at different levels of adherence.Adherence was measured with unannounced pill counts performed at the participant's usual place of residence in a prospective cohort of HIV-positive urban poor individuals. Two genotypic resistance tests separated by 6 months (G1 and G2) were obtained in individuals on a stable regimen and with detectable viremia (> 50 copies/ml). The primary resistance outcome was the number of new HIV antiretroviral drug resistance mutations occurring over the 6 months between G1 and G2.High levels of adherence were closely associated with greater time on treatment (P < 0.0001) and viral suppression (P < 0.0001) in 148 individuals. In a subset of 57 patients with a plasma viral load > 50 copies/ml on stable therapy, the accumulation of new drug resistance mutations was positively associated with the duration of prior treatment (P = 0.03) and pill count adherence (P = 0.002). Assuming fully suppressed individuals (< 50 copies/ml) do not develop resistance, it was estimated that 23% of all drug resistance occurs in the top quintile of adherence (92-100%), and over 50% of all drug resistance mutations occur in the top two quintiles of adherence (79-100%).Increasing rates of viral suppression at high levels of adherence is balanced by increasing rates of drug resistance among viremic patients. Exceptionally high levels of adherence will not prevent population levels of drug resistance.
View details for DOI 10.1097/01.aids.0000076320.42412.fd
View details for Web of Science ID 000185067700008
View details for PubMedID 12960825
An open-label randomized clinical trial of novel therapeutic strategies for HIV-infected patients in whom antiretroviral therapy has failed: rationale and design of the OPTIMA Trial
CONTROLLED CLINICAL TRIALS
2003; 24 (4): 481-500
OPTIMA (OPTions In Management with Antiretrovirals) is a clinical trial with a factorial randomization to evaluate the hypotheses that mega-antiretroviral therapy (ART) consisting of five or more anti-HIV drugs compared to standard-ART consisting of four or fewer anti-HIV drugs and a 3-month antiretroviral drug-free period (ARDFP) compared to no ARDFP will delay the occurrence of new or recurrent acquired immunodeficiency syndrome events or death, and prove to be more cost-effective in treating human immunodeficiency virus-infected individuals previously exposed to ART drugs from the current three main classes. The aim is to randomize 1,700 participants to four treatment strategy arms: (1) ARDFP+standard-ART; (2) ARDFP+mega-ART; (3) no ARDFP+standard-ART; (4) no ARDFP+mega-ART. The planned study duration is 3.5 years with 2.5 years of intake and a minimum 1 year of follow-up. The OPTIMA Trial was initiated in June 2001 at 30 U.S. Department of Veterans' Affairs hospitals, 22 hospitals in Canada, and 25 hospitals in the United Kingdom. This is the first large-scale, multicenter, randomized controlled trial to compare the relative efficacy of these different therapeutic strategies. We discuss the rationale behind the OPTIMA Trial design as well as the issues arising from the conduct of a trial that involves three national clinical trial agencies.
View details for DOI 10.1016/S0197-2456(03)00029-1
View details for Web of Science ID 000184355000010
View details for PubMedID 12865041
Successful management of disseminated Nocardia transvalensis infection in a heart transplant recipient after development of sulfonamide resistance: Case report and review
JOURNAL OF HEART AND LUNG TRANSPLANTATION
2003; 22 (4): 492-497
Nocardia transvalensis is a rarely reported cause of clinically significant disease, and, to our knowledge, has not been reported previously as a cause of infection in the cardiac transplant population. We report a case of N transvalensis new taxon-2 pulmonary infection that disseminated to the brain and skin in a cardiac transplant recipient despite adequate sulfonamide serum levels. Subsequent isolates were resistant to sulfonamides, and molecular ribotyping of the primary and subsequent isolates confirmed that these were the same N transvalensis new taxon-2 strain. The taxonomic and diagnostic considerations, as well as the clinical significance of anti-microbial-resistant nocardia, are reviewed and discussed herein.
View details for DOI 10.1016/S1053-2498(02)00663-0
View details for Web of Science ID 000182020300017
View details for PubMedID 12681430
Accuracy of the TRUGENE HIV-1 genotyping kit
JOURNAL OF CLINICAL MICROBIOLOGY
2003; 41 (4): 1586-1593
Drug resistance and poor virological responses are associated with well-characterized mutations in the viral reading frames that encode the proteins that are targeted by currently available antiretroviral drugs. An integrated system was developed that includes target gene amplification, DNA sequencing chemistry (TRUGENE HIV-1 Genotyping Kit), and hardware and interpretative software (the OpenGene DNA Sequencing System) for detection of mutations in the human immunodeficiency virus type 1 (HIV-1) protease and reverse transcriptase sequences. The integrated system incorporates reverse transcription-PCR from extracted HIV-1 RNA, a coupled amplification and sequencing step (CLIP), polyacrylamide gel electrophoresis, semiautomated analysis of data, and generation of an interpretative report. To assess the accuracy and robustness of the assay system, 270 coded plasma specimens derived from nine patients were sent to six laboratories for blinded analysis. All specimens contained HIV-1 subtype B viruses. Results of 270 independent assays were compared to "gold standard" consensus sequences of the virus populations determined by sequence analysis of 16 to 20 clones of viral DNA amplicons derived from two independent PCRs using primers not used in the kit. The accuracy of the integrated system for nucleotide base identification was 98.7%, and the accuracy for codon identification at 54 sites associated with drug resistance was 97.6%. In a separate analysis of plasma spiked with infectious molecular clones, the assay reproducibly detected all 72 different drug resistance mutations that were evaluated. There were no significant differences in accuracy between laboratories, between technologists, between kit lots, or between days. This integrated assay system for the detection of HIV-1 drug resistance mutations has a high degree of accuracy and reproducibility in several laboratories.
View details for DOI 10.1128/JCM.41.4.1586-1593.2003
View details for Web of Science ID 000182179900037
View details for PubMedID 12682149
Impact of highly active antiretroviral therapy and immunologic status on hepatitis C virus quasispecies diversity in human immunodeficiency virus/hepatitis C virus-coinfected patients
JOURNAL OF VIROLOGY
2003; 77 (3): 1940-1950
This study analyzes the effect of highly active antiretroviral therapy (HAART), and thus immunologic status, on hepatitis C virus (HCV) load and quasispecies diversity in patients coinfected with the human immunodeficiency virus (HIV) and HCV. Three cohorts of coinfected patients were analyzed retrospectively over a period of 7 to 10 months: group A was antiretroviral drug naïve at baseline and then on HAART for the remainder of the study, group B did not receive antiretroviral therapy at any point, and group C was on HAART for the entire study. HCV quasispecies diversity was analyzed by sequencing hypervariable region 1. In a longitudinal analysis, there was no significant change from baseline in any immunologic, virologic, or quasispecies parameter in any of the three groups. However, in comparison to groups A and B, group C had significantly higher CD4+- and CD8+-cell counts, a trend toward a higher HCV load, and significantly increased number of HCV clones, entropy, genetic distance, and ratio of nonsynonymous substitutions per nonsynonymous site to synonymous substitutions per synonymous site (Ka/Ks). In addition, CD4+-cell count was positively correlated with HCV load, genetic distance, and Ka. Interestingly, patients infected with HCV genotype 2 or 3 had a significantly higher CD4+-cell count, HCV load, genetic distance, and Ka/Ks than those infected with genotype 1. These results suggest that there is no immediate effect of HAART on HCV but that, with prolonged HAART, immune restoration results in an increase in HCV load and quasispecies diversity.
View details for DOI 10.1128/JVI.77.3.1940-1950.2003
View details for Web of Science ID 000180488700030
View details for PubMedID 12525628
- Role of Deoxyribonucleoside Kinases and Deoxyribonucleotide Pool Alterations in Nucleoside Reverse Transcriptase Inhibitor Induced Mitochondrial Toxicity Curr. Med. Chem. - Anti-Infective Agents 2003; 2: 241-262
HIV-1 RNA and viral load
CLINICS IN LABORATORY MEDICINE
2002; 22 (3): 593-?
Viral load monitoring has become the standard of care in clinical practice to assess risk for disease progression and to monitor treatment response. Furthermore, viral load monitoring has contributed greatly to the understanding of HIV disease pathogenesis and response to various antiretroviral regimens, and has broadened its applications to include blood bank screening. The assays that are currently available are more sensitive, precise, and robust. There is now a better understanding of their limitations and the clinical scenarios and assay performance issues that result in variations of viral load results.
View details for Web of Science ID 000178324900003
View details for PubMedID 12244588
A pilot trial of indinavir, ritonavir, didanosine, and lamivudine in a once-daily four-drug regimen for HIV infection
JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES
2001; 27 (3): 260-265
To evaluate the tolerance, pharmacokinetics, and virologic and immunologic outcomes of once-daily indinavir, ritonavir, didanosine, and lamivudine in HIV-seropositive individuals.Open-label 24-week pilot study.Ten HIV-seropositive subjects who were either antiretroviral-naive or minimally experienced with short-term single-or dual-nucleoside therapy provided informed consent and were enrolled. All subjects received didanosine (400 mg) 30 to 60 minutes before a meal followed by indinavir (1200 mg), ritonavir (400 mg), and lamivudine (300 mg) concurrent with the aforementioned meal.Safety laboratory tests, including a complete blood cell count and amylase, lipase, liver transaminase, and nonfasting lipid monitoring as well as plasma HIV viral load and CD4+ lymphocyte count, were carried out at monthly intervals. Genotyping was performed at baseline. Pharmacokinetic studies for indinavir and ritonavir were performed at week 8.Nine of 10 subjects completed 24 weeks of therapy. No subject demonstrated primary protease inhibitor mutations at baseline. Toxicities experienced by subjects were typically mild and consistent with those commonly reported for each of the medications, including two cases of hematuria. By week 24, median nonfasting cholesterol and triglyceride levels increased by 49% and 108%, respectively. Median baseline plasma HIV viral load and CD4+ lymphocyte count were 29,292 (4.47 log10) copies/ml and 224 cells/mm3, respectively. Eight of 10 subjects had a plasma HIV viral load of <50 copies/ml by week 12. The 2 subjects with a detectable HIV viral load reached <50 copies/ml by week 28. Median CD4+ lymphocyte counts increased by 193 cells/mm3 at week 24. Indinavir and ritonavir plasma concentrations remained above respective inhibitory and effective concentrations (IC95 and EC50) (uncorrected for protein binding) throughout the 24-hour dosing interval for 6 of 10 and 8 of 10 subjects, respectively.Our pilot study demonstrates excellent virologic suppression despite low minimum protease inhibitor concentrations during a dosing interval in some patients and is supportive of further study.
View details for Web of Science ID 000169840800007
View details for PubMedID 11464145
Multinodular polymyositis in a patient with human immunodeficiency and hepatitis C virus coinfection
MUSCLE & NERVE
2001; 24 (3): 433-437
We report a patient who developed multiple inflammatory muscle masses and generalized polymyositis in the setting of combined human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection. Magnetic resonance imaging (MRI) of muscles showed patchy edema which was particularly intense within the nodular masses. Polymerase chain reaction (PCR) showed no evidence of either virus within muscle. This report reviews earlier literature on muscle nodules associated with myositis and discusses the differential diagnosis of muscle masses in HIV infection.
View details for Web of Science ID 000167117100020
View details for PubMedID 11353433
HIV resistance testing--has it come of age?
2000; 10 (8): 474-475
View details for PubMedID 10967807
Assessment of developmental toxicity of antiretroviral drugs using a rat whole embryo culture system
2000; 62 (2): 108-114
Previous guidelines for HIV-infected pregnant women have recommended zidovudine (ZDV) monotherapy during the second and third trimesters of pregnancy to prevent fetal HIV infection. New guidelines suggest that women should continue or be offered combination antiretroviral therapy (including protease inhibitors) during pregnancy. Nevertheless, little animal or human toxicity data underlie these recommendations.We used an in vitro rat whole embryo culture system to assess the embryo toxicity of various nucleoside analogues, namely, ZDV, dideoxyinosine (ddI), and 2', 3'-dideoxycytidine (ddC), and the HIV-1 protease inhibitor, indinavir, both alone and in combination.Although human fetal concentrations of these compounds are unknown, no gross abnormalities were detected after incubation with these agents, either alone or in combination at concentrations that would be expected to be achievable in human maternal serum (1-50 microM). ZDV in combination with ddC at >100 microM, resulted in severe growth retardation and morphologic abnormalities not seen with either agent singly.We conclude that the combination of ZDV/ddC results in severe concentration-dependent embryo toxicity. No growth retardation or gross morphologic abnormalities were found for any of the agents, either singly or in combination, at clinically relevant concentrations.
View details for Web of Science ID 000088528900007
View details for PubMedID 10931508
Adherence to protease inhibitors, HIV-1 viral load, and development of drug resistance in an indigent population
2000; 14 (4): 357-366
To examine the relationship between adherence, viral suppression and antiretroviral resistance in HIV-infected homeless and marginally housed people on protease inhibitor (PI) therapy.A cross-sectional analysis of subjects in an observational prospective cohort systematically sampled from free meal lines, homeless shelters and low-income, single-room occupancy (SRO) hotels.Thirty-four HIV-infected people with a median of 12 months of PI therapy.Adherence measured by periodic unannounced pill counts, electronic medication monitoring, and self-report; HIV RNA viral load; and HIV-1 genotypic changes associated with drug resistance.Median adherence was 89, 73, and 67% by self-report, pill count, and electronic medication monitor, respectively. Thirty-eight per cent of the population had over 90% adherence by pill count. Depending on the measure, adherence explained 36-65% of the variation in concurrent HIV RNA levels. The three adherence measures were closely related. Of 20 genotyped patients who received a new reverse transcriptase inhibitor (RTI) when starting a PI, three had primary protease gene substitutions. Of 12 genotyped patients who received a PI without a new RTI, six had primary protease gene substitutions (P < 0.03).A substantial proportion of homeless and marginally housed individuals had good adherence to PI therapy. A strong relationship was found between independent methods of measuring adherence and concurrent viral suppression. PI resistance was more closely related to the failure to change RTI when starting a PI than to the level of adherence.
View details for Web of Science ID 000086155800008
View details for PubMedID 10770537
Stability of plasma human immunodeficiency virus load in VACUTAINER PPT plasma preparation tubes during overnight shipment
JOURNAL OF CLINICAL MICROBIOLOGY
2000; 38 (1): 323-326
VACUTAINER PPT plasma preparation tubes were evaluated to determine the effects of various handling and shipping conditions on plasma human immunodeficiency virus (HIV) load determinations. Plasmas obtained from PPT tubes stored and shipped under nine different conditions were compared to conventional EDTA tube plasmas stored at -70 degrees C within 2 h after phlebotomy. Compared to viral loads in frozen EDTA plasma, those in PPT tube plasma that was frozen immediately and either separated or shipped in situ were not significantly different. Viral loads in PPT tube plasma after storage for 6 h at either room temperature or 4 degrees C, followed by shipment at ambient temperature or on wet or dry ice, were not significantly different from baseline viral loads in EDTA or PPT plasma. The results of this study indicate that the HIV load in PPT tube plasma is equivalent to that in standard EDTA plasma. Plasma viral load is not affected by storage or shipment temperature when plasma is collected in PPT tubes. Furthermore, plasmas can be shipped in spun PPT tubes, and the tubes provide a safer and more convenient method for sample collection and transport than regular EDTA tubes.
View details for Web of Science ID 000084689800057
View details for PubMedID 10618109
A double blind, randomized, placebo-controlled phase II study to assess the safety and efficacy of orally administered SP-303 for the symptomatic treatment of diarrhea in patients with AIDS
AMERICAN JOURNAL OF GASTROENTEROLOGY
1999; 94 (11): 3267-3273
The aim of this study was to investigate the safety and effectiveness of orally administered SP-303 in patients with AIDS and diarrhea.This is a multicenter, phase II, randomized, double blind, placebo-controlled study. HIV-positive subjects with a history of a CD4 count <200 or an AIDS-defining illness were admitted to an inpatient study unit and screened for diarrhea defined as at least three abnormal (i.e., soft or watery) stools and >200 g of abnormal stool weight over a 24-h period. Subjects discontinued all antidiarrheal agents >24 h before enrollment. Stool samples were studied for routine pathogens. Subjects received 500 mg p.o. of SP-303 or placebo every 6 h for 96 h (4 days). Stool frequency and weights were recorded. Subjects were monitored for symptoms and side effects and were seen 1 wk later in follow-up.A total of 26 subjects received SP-303, and 25 received placebo. There were no significant demographic differences between treatment arms. A total of 41 subjects (80%) were receiving antiretroviral therapy and 39 subjects (77%) were receiving at least one protease inhibitor. Stool studies revealed no pathogens in 48 of 51 patients (94%). There were no serious adverse events or laboratory abnormalities. The SP-303 treatment group demonstrated a mean reduction from baseline stool weight of 451 g/24 h versus 150 g/24 h with placebo on day 4 of treatment (p = 0.14), and a mean reduction in abnormal stool frequency of three abnormal stools in 24 h versus two in 24 h in the placebo group (p = 0.30). Daily measures analysis over 4 days of treatment demonstrated that SP-303 subjects had a significant reduction in stool weight (p = 0.008) and abnormal stool frequency (p = 0.04) when compared to placebo-treated subjects.SP-303 is safe and well tolerated. These results suggest that SP-303 may be effective in reducing stool weight and frequency in patients with AIDS and diarrhea.
View details for Web of Science ID 000083596500033
View details for PubMedID 10566728
Decreased medical expenditures for care of HIV-seropositive patients - The impact of highly active antiretroviral therapy at a US Veterans Affairs Medical Center
1999; 16 (3): 307-315
To identify any changes in expenditures and in morbidity and mortality with the progression of treatment of the HIV-seropositive population from monotherapy with a nucleoside reverse transcriptase inhibitor (NRTI)  through dual NRTI therapy (1995) to highly active antiretroviral therapy (HAART) .This study retrospectively compared 3 separate years of the total expenditures encountered in the management of HIV-seropositive individuals seen at a US Veterans Affairs Medical Center.Utilising a computerised hospital database, we identified those patients with HIV-related International Classification of Diseases, version 9 (ICD-9) codes and collected all healthcare-related expenditure data. The 3 eras selected for comparison were controlled for similar utilisation of prophylaxis against opportunistic infections, access to investigational antivirals, consistency between primary care providers and distribution of new anti-HIV therapies relative to that era. Cost data for inpatient and outpatient activities (visits and admissions) were derived from actual expenditures. Major categories were then compared, including total inpatient/outpatient expenditures and utilisation, laboratory and prescription costs, and morbidity and mortality rates.The 3 periods had similar patient populations, with 86, 86 and 82% of patients in 1993, 1995 and 1997, respectively, having some degree of immunosuppression (defined as CD4+ lymphocyte counts < 500 cells/mm3). Morbidity and mortality were not changed by the addition of dual NRTI therapy. HAART therapy produced 60 and 70% declines in relative mortality when compared with the single and dual NRTI eras. Dual NRTI or HAART therapy decreased overall expenditures as compared with NRTI monotherapy. HIV-related outpatient resource utilisation other than pharmacy and laboratory costs fell by 25 and 59% in 1997 as compared with 1993 and 1995, respectively. The greatest fall in resource utilisation was for inpatient bed-days of care, where the average cost per patient fell by $US2782 between 1993 and 1997. Pharmacy and laboratory expenditures increased by $US1825 and $US231 per patient from 1993 to 1997, respectively. Overall, the impact of HAART was a decrease of $US1193 in the average total cost per patient from 1993 to 1997.The introduction of HAART provided a positive outcome on patient morbidity and mortality and on medical centre expenditures. The end result was a cost shift of expenditures from inpatient utilisation to outpatient pharmacy and laboratory costs. This information is important for patients and providers, who need to make clinical decisions on lifelong therapies, and for healthcare financial planners, who need to predict inpatient and outpatient healthcare utilisation during an era of limited healthcare dollars.
View details for Web of Science ID 000082728900007
View details for PubMedID 10558042
Viral Load Monitoring in HIV Infection.
Current infectious disease reports
1999; 1 (5): 497-503
Measurement of HIV-1 viral load is now an accepted part of clinical practice for the determination of clinical prognosis and antiretroviral effectiveness in HIV infection. Consensus guidelines have been published on the appropriate use of this testing. Furthermore, recent advances in molecular technology have improved the sensitivity and reproducibility of viral load assays, and these improved assays have provided new insight into the pathogenesis of HIV disease. This article reviews new issues affecting viral load quantification, including viral subtypes, sex, compartmental differences, and other covariables.
View details for PubMedID 11095829
Effects of collection, processing, and storage on RNA detection and quantification.
Methods in molecular medicine
1999; 26: 43-59
Historically, clinicians and researchers have relied upon the development of clinical endpoints or the use of surrogate markers in the evaluation of disease pathogenesis and in response to various therapeutic agents. In addition, microbiologic methods of detecting various pathogens have usually required the culture of an agent. The majority of bacterial pathogen culture methods have been standardized and identification has become relatively straightforward. Nonetheless, a wide variety of unculturable pathogens have been identified. Recent advances in molecular diagnostics have provided clinicians with the ability to measure directly infectious agents. Certain viral pathogens such as human immunodeficiency virus (HIV) are detectable by standard culture techniques whereas others such as hepatitis C virus (HCV) are not.
View details for DOI 10.1385/0-89603-518-2:43
View details for PubMedID 21340869
Controversies in AIDS treatment. Proceedings from CME conference sponsored by Cornell University Medical College and the American Foundation for AIDS Research (AmFAR). November 8, 1997. Faculty roundtable discussion.
AIDS patient care and STDs
1998; 12 (7): 543-555
View details for PubMedID 15462006
Controversies in AIDS treatment. Proceedings from CME conference sponsored by Cornell University Medical College and the American Foundation for AIDS Research (AmFAR). November 8, 1997. Question and answer session.
AIDS patient care and STDs
1998; 12 (7): 557-566
View details for PubMedID 15462007
- Phenotypic and genotypic testing in clinical practice AIDS PATIENT CARE AND STDS 1998; 12 (7): 527-531
Zidovudine treatment in patients with primary (Acute) human immunodeficiency virus type 1 infection: A randomized, double-blind, placebo-controlled trial
JOURNAL OF INFECTIOUS DISEASES
1998; 178 (1): 80-91
A multicenter, double-blind, placebo-controlled trial randomized 28 patients with primary (acute) human immunodeficiency virus (HIV)-1 infection (PHI) to receive zidovudine, 1000 mg daily, or placebo for 24 weeks. At week 48, compared with placebo patients, zidovudine-treated patients had significantly higher CD4 cell counts (zidovudine, 666 cells/mm3; placebo, 362; P = .004) and lower peripheral blood mononuclear cell (PBMC) culture titers (zidovudine, 0.58 log infectious units per million cells; placebo, 1.68; P = .02) but no difference in plasma RNA (zidovudine, 3.93 log copies/mL; placebo, 4.00; P = .83). Serious adverse events and minor clinical events were infrequent and comparable in both arms. There were two deaths: 1 patient died of sepsis and renal disease (zidovudine arm), and 1 patient died of sepsis and tension pneumothorax (placebo arm). Six months of high-dose zidovudine initiated during PHI results in higher CD4 cell counts and lower PBMC culture titers but no difference in plasma HIV-1 RNA. Further studies with more potent antiretroviral combination therapies are warranted.
View details for Web of Science ID 000074357900011
View details for PubMedID 9652426
HIV quantitation in spiked vaginocervical secretions: lack of non-specific inhibitory factors
JOURNAL OF VIROLOGICAL METHODS
1998; 72 (2): 185-195
The objective of this study was to assess the effect of menstrual phase on the ability to quantitate HIV-1 in vaginocervical secretions (VCS) through reconstruction experiments with HIV seronegative VCS collected throughout the menstrual cycle. Measurement of HIV-1 inoculated into both fresh and frozen VCS was undertaken by quantitative micro co-culture, p24 antigen assay and polymerase chain reaction (PCR) for both HIV-1 RNA and pro-viral DNA. Two laboratories carried out these assays over a range of viral concentrations. The study involved a randomized factorial design and the factors were: (1) diluents (phases of the menstrual cycle and controls); (2) laboratories; (3) stock concentrations; and (4) frozen versus fresh VCS samples. Each assay was assessed independently using a random effects analysis of variance (ANOVA) model. No statistical differences due to menstrual cycle were seen in the assay results of p24 antigen (P = 0.08), PBMC culture (P = 0.74), plasma culture (P = 0.13), cell-free RNA (P = 0.44), cell-associated RNA (P = 0.58) and cell-associated DNA (P = 0.43). Inter-laboratory differences were statistically significant for cell-free RNA (P < 0.001), cell-associated DNA (P < 0.001) and p24 (P < 0.001). It is concluded that VCS obtained throughout the menstrual cycle from HIV-uninfected women lacks intrinsic inhibitory factors which could limit detection and quantification by antigen, culture or nucleic acid-based technologies for HIV-1 in VCS throughout the menstrual cycle. Using a standardized collection procedure, we suggest that variation in HIV quantity over time, when reported in VCS of infected women, should be attributed to HIV-associated biologic factors, rather than non-specific or other technical factors.
View details for Web of Science ID 000074790000007
View details for PubMedID 9694326
Simultaneous genotyping and species identification using hybridization pattern recognition analysis of generic Mycobacterium DNA arrays
1998; 8 (5): 435-448
High-density oligonucleotide arrays can be used to rapidly examine large amounts of DNA sequence in a high throughput manner. An array designed to determine the specific nucleotide sequence of 705 bp of the rpoB gene of Mycobacterium tuberculosis accurately detected rifampin resistance associated with mutations of 44 clinical isolates of M. tuberculosis. The nucleotide sequence diversity in 121 Mycobacterial isolates (comprised of 10 species) was examined by both conventional dideoxynucleotide sequencing of the rpoB and 16S genes and by analysis of the rpoB oligonucleotide array hybridization patterns. Species identification for each of the isolates was similar irrespective of whether 16S sequence, rpoB sequence, or the pattern of rpoB hybridization was used. However, for several species, the number of alleles in the 16S and rpoB gene sequences provided discordant estimates of the genetic diversity within a species. In addition to confirming the array's intended utility for sequencing the region of M. tuberculosis that confers rifampin resistance, this work demonstrates that this array can identify the species of nontuberculous Mycobacteria. This demonstrates the general point that DNA microarrays that sequence important genomic regions (such as drug resistance or pathogenicity islands) can simultaneously identify species and provide some insight into the organism's population structure.
View details for Web of Science ID 000073748300007
View details for PubMedID 9582189
Human immunodeficiency virus type 1 populations in blood and semen
JOURNAL OF VIROLOGY
1998; 72 (1): 617-623
Transmission of human immunodeficiency virus type 1 (HIV-1) usually results in outgrowth of viruses with macrophage-tropic phenotype and consensus non-syncytium-inducing (NSI) V3 loop sequences, despite the presence of virus with broader host range and the syncytium-inducing (SI) phenotype in the blood of many donors. We examined proviruses in contemporaneous peripheral blood mononuclear cells (PBMC) and non-spermatozoal semen mononuclear cells (NSMC) of five HIV-1-infected individuals to determine if this preferential outgrowth could be due to compartmentalization and thus preferential transmission of viruses of the NSI phenotype from the male genital tract. Phylogenetic reconstructions of approximately 700-bp sequences covering the second constant region through the fifth variable region (C2 to V5) of the viral envelope gene revealed distinct variant populations in the blood versus the semen in two patients with AIDS and in one asymptomatic individual (patient 613), whereas similar variant populations were found in both compartments in two other asymptomatic individuals. Variants with amino acids in the V3 loop that predict the SI phenotype were found in both AIDS patients and in patient 613; however, the distribution of these variants between the two compartments was not consistent. SI variants were found only in the PBMC of one AIDS patient but only in the NSMC of the other, while they were found in both compartments in patient 613. It is therefore unlikely that restriction of SI variants from the male genital tract accounts for the observed NSI transmission bias. Furthermore, no evidence for a semen-specific signature amino acid sequence was detected.
View details for Web of Science ID A1998YL01000073
View details for PubMedID 9420266
HIV-1 protease inhibitors - A review for clinicians
JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION
1997; 277 (2): 145-153
The clinical care of people infected with human immunodeficiency virus (HIV) has been substantially affected by the introduction of HIV-specific protease inhibitors (PIs). The 4 PIs available are saquinavir mesylate, ritonavir, indinavir sulfate, and nelfinavir mesylate. Comparison studies have not been reported; therefore, an assessment of the available data to aid clinicians and patients in choosing appropriate treatment will be presented.A systematic review of peer-reviewed publications, abstracts from national and international conferences, and product registration information through September 1996.Criteria used to select studies include their relevance to PIs, having been published in the English language, and pertinence for clinicians. Data quality and validity included the venue of the publication and relevance to clinical care.Oral adminstration of ritonavir, indinavir, or nelfinavir generates sustainable drug serum levels to effectively inhibit the protease enzyme; however, saquinavir may not generate sustained levels necessary to inhibit the protease enzyme. Patients treated with ritonavir, indinavir, or nelfinavir experience similar reductions in viral load and increases in CD4+ lymphocytes; smaller effects occur among those treated with saquinavir. Two randomized placebo-controlled studies conducted among patients with severe immune system suppression and substantial zidovudine treatment experience demonstrated reduced HIV disease progression and reduced mortality with PI treatment. Genotypic resistance to PIs occurs; the clinical relevance of resistance is unclear. The costs of these agents including required monitoring impose new and substantial costs.The PIs have emerged as critical drugs for people with HIV infection. Optimal use involves combination with reverse transcriptase inhibitors. Resistance develops to each agent, and cross-resistance is likely. These agents must be used at full doses with attention to ensuring patient compliance. The expense of these agents may be offset by forestalling disease progression and death and returning people to productive life. Selecting the initial PI must be individualized, and factors to consider include proven activity, possible toxicities, dosing regimens, drug interactions, and costs.
View details for Web of Science ID A1997WA65000036
View details for PubMedID 8990341
Prescribing practice and cost of antibacterial prophylaxis for surgery at a US Veterans Affairs Hospital
1996; 10 (6): 630-643
This study retrospectively compared the actual drug-related cost of antibacterial prophylaxis for specific operative procedures with the theoretical costs based on recommendations published in Medical Letter on Drugs and Therapeutics, the Surgical Infection Society, and those of the chiefs of each surgical subspecialty at our institution. We identified all patients who received in intravenous bacterial for prophylaxis before a clean or clean-contaminated operation between 1st January and 30th September 1993, using the medical centre's computerised information system. The information included comprehensive surgical case histories, and pharmacy and microbiology records. Only those operations in which recommendations for surgical prophylaxis were present in all 3 guidelines were included. The outcome measures were antibacterial-related costs (drug acquisition and administration costs), the number of antibacterial doses dispensed, and choice of antibacterial agents. During the study period, 3,322 operations were performed, 2,993 of which were excluded. Thus, 329 patients undergoing operations in 6 subspecialties were included in the analysis. The actual mean cost per patient significantly exceeded the projected costs using Medical Letter Consultants' and Surgical Infection Society guidelines for all 6 subspecialties [mean excess cost per patient: $US49.04 and $US34.95, respectively (1994 values)] and institutional guidelines for 4 of the 6 subspecialties (mean excess cost per patient: $US24.36). The actual mean number of doses per patient significantly exceeded those projected using Medical Letter Consultants' and Surgical Infection Society guidelines for all 6 subspecialties (mean excess number of doses per patient: 6.0 and 4.0, respectively) and institutional guidelines for 4 of the 6 subspecialties (mean excess number of doses per patient: 2.9). The choice of antibacterial was appropriate in approximately 90% of cases. We conclude that the practice of antibacterial prophylaxis for specific operative procedures performed by 6 subspecialties is not in accordance with institutional or published guidelines, and the excess cost is primarily a result of prolonged duration of antibacterial prophylaxis.
View details for Web of Science ID A1996VX12000009
View details for PubMedID 10164063
Evaluation of Chiron HIV-1/HIV-2 recombinant immunoblot assay
JOURNAL OF CLINICAL MICROBIOLOGY
1996; 34 (11): 2650-2653
In a study to determine the reliability, sensitivity, and specificity of the Chiron RIBA HIV-1/HIV-2 Strip Immunoblot Assay (RIBA HIV-1/2 SIA) for confirmation of human immunodeficiency virus type 1 (HIV-1) and HIV-2 antibodies, 1,263 serum samples from various populations in the United States, Caribbean, Africa, India, and Thailand were evaluated by RIBA HIV-1/2 SIA, and the results were compared with those obtained by an HIV-1 Western blot (immunoblot) assay. All sera were tested by HIV enzyme immunoassay, RIBA HIV-1/2 SIA, and Western blotting. Samples with discrepant results were further tested by an HIV-1 and/or HIV-2 immunofluorescent-antibody assay and HIV-1 p24 antigen assay. The RIBA HIV-1/2 SIA detected all 17 HIV-1 and HIV-2 dually reactive serum samples, all 215 HIV-2-positive serum samples, and 480 of 481 HIV-1-positive serum samples for a sensitivity of 99.8%. Of 548 negative samples, 523 were RIBA HIV-1/2 SIA negative, for a specificity of 95.4%, with 22 (4%) samples interpreted as indeterminate and 3 (0.6%) interpreted as falsely positive. Western blotting detected 391 of 548 negative samples (specificity, 71.4%), with 152 (27.7%) samples interpreted as indeterminate and 5 (0.9%) interpreted as falsely positive. In conclusion, the RIBA HIV-1/2 SIA had a sensitivity comparable to that of Western blotting and could discriminate HIV-1 from HIV-2 in one blot, providing a cost advantage. Because of its high degree of specificity, the RIBA HIV-1/2 SIA further reduced the number of indeterminate results found by Western blotting, providing a more accurate means of assessing seronegative individuals.
View details for Web of Science ID A1996VM55600003
View details for PubMedID 8897158
Human immunodeficiency virus reverse transcriptase codon 215 mutations diminish virologic response to didanosine-zidovudine therapy in subjects with non-syncytium-inducing phenotype
JOURNAL OF INFECTIOUS DISEASES
1996; 174 (4): 854-857
Eight zidovudine-experienced subjects received zidovudine and didanosine for 30 weeks followed by 30 weeks of didanosine monotherapy. At study entry, plasma from 4 subjects had human immunodeficiency virus RNA pol T215Y/F mutant and 4 had codon 215 wild type. All 8 subjects had non-syncytium-inducing virus phenotype. Sustained 10-fold decreases in plasma RNA levels were seen only in subjects who initially had 215 wild type RNA, despite the development of a T215Y/F mutation during combination therapy. Virologic and immunologic benefits were maintained in this group with didanosine monotherapy. No subject developed a pol L74V codon mutation. Significant differences in plasma virus load and CD4 cell responses were seen in this zidovudine-didanosine combination pilot study relative to codon 215 genotype.
View details for Web of Science ID A1996VK04500027
View details for PubMedID 8843229
HIV viral load markers in clinical practice
1996; 2 (6): 625-629
Plasma HIV RNA determinations are an important prognostic marker of disease progression and, when used appropriately, provide a valuable tool for the management of individual patients. But what constitutes appropriate use?
View details for Web of Science ID A1996UN69100022
View details for PubMedID 8640545
A meta-analytic evaluation of the polymerase chain reaction for the diagnosis of HIV infection in infants
JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION
1996; 275 (17): 1342-1348
To evaluate the sensitivity and specificity of the polymerase chain reaction (PCR) for the diagnosis of infection with human immunodeficiency virus (HIV) in infants.We used studies published between 1988 and 1994 identified in a literature search of 17 databases, including MEDLINE.Studies were included if DNA amplification by PCR was performed on peripheral blood mononuclear cells from infants or children.Two investigators independently extracted data. The study design was assessed independently by 2 investigators who were blinded to study results.Thirty-two studies met the inclusion criteria and were analyzed. The median reported sensitivity was 91.6% (range, 31%-100%), and the median specificity was 100% (range, 50%-100%). A summary receiver operating characteristic curve based on all 32 studies indicated that PCR has a maximum joint sensitivity and specificity between 93.2% and 94.9%. Subgroup analysis indicated that the joint sensitivity and specificity was significantly (P = .04) higher in older infants (98.2%) than in neonates (aged < or = 30 days; 93.3%). For infants at low risk of perinatal transmission (probability of transmission, 8.3%), the positive predictive value for PCR is 55.8% in neonates and 83.2% in older infants. A negative PCR result reduces the probability of HIV infection to less than 3%. No studies met all criteria for study design.Although PCR is one of the best available tests for diagnosis of HIV infection in neonates and infants, it is not definitive. Therefore, PCR should be interpreted with the aid of careful clinical follow-up examinations. The sensitivity and specificity of PCR in neonates is lower than in older infants, which results in a low positive predictive value; however, negative tests are informative. Delaying the use of PCR until after the neonatal period or repeating PCR on independent samples obtained 30 to 60 days later will reduce test errors.
View details for Web of Science ID A1996UG61200032
View details for PubMedID 8614121
Polymerase chain reaction for the diagnosis of HIV infection in adults - A meta-analysis with recommendations for clinical practice and study design
ANNALS OF INTERNAL MEDICINE
1996; 124 (9): 803-?
To do a meta-analysis of studies that have evaluated the sensitivity and specificity of polymerase chain reaction (PCR) assay for the diagnosis of human immunodeficiency virus (HIV) infection in adults. Evaluating the performance of PCR is difficult because in certain clinical situations, the sensitivity or specificity of PCR may exceed those of the current reference standard tests (enzyme immunoassay followed by confirmatory Western blot analysis). Therefore, an additional goal was to develop recommendations for 1) the design of future evaluative studies of PCR and 2) the use of PCR in persons with suspected HIV infection.Studies published between 1988 and 1994 that were identified in a search of 17 computer databases, including MEDLINE, and abstracts identified from conference proceedings.Studies were included if DNA amplification by PCR was done on peripheral blood mononuclear cells from adults. Ninety-six studies met the inclusion criteria.Data were extracted independently by two reviewers. Study design was assessed independently by two investigators blinded to study results.Reported sensitivities for PCR range from 10% to 100%, and specificities range from 40% to 100%. A summary receiver-operating characteristic curve based on all 96 studies has a maximum joint sensitivity and specificity (upper left point on the curve, where sensitivity equals specificity) of 97.0% to 98.1%. If the threshold value that defines a positive PCR result is chosen so that sensitivity is higher than 98.1%, specificity will decrease to less than 98.1%. Conversely, if the threshold value that defines a positive PCR result is chosen so that specificity is greater than 98.1%, sensitivity will decrease to less than 98.1%. If sensitivity and specificity are chosen to be equal, the corresponding false-positive rate is 1.9% to 3.0%. At the maximum joint sensitivity and specificity, the positive predictive value of PCR ranges from 34% to 85% as the prevalence of HIV increases from 1.0% to 10%. We identified seven areas in which study design could be modified to 1) reduce susceptibility to bias in estimates of the sensitivity and specificity of PCR and 2) to increase the generalizability of the study results. These modifications will also help to overcome methodologic problems created by the lack of a reference standard test.The PCR assay is not sufficiently accurate to be used for the diagnosis of HIV infection without confirmation. Use of PCR for the diagnosis of HIV in adults should be limited to situations in which antibody tests are known to be insufficient. Future studies of PCR performance should be sufficiently large and should use adequate reference standard tests and standardized methods for the performance of PCR. Specimens should be evaluated by persons blinded to clinical status and to the results of other diagnostic tests for HIV infection.
View details for Web of Science ID A1996UG25400004
View details for PubMedID 8610949
Antiretroviral monotherapy in early stage human immunodeficiency virus disease has no detectable effect on virus load in peripheral blood and lymph nodes
JOURNAL OF INFECTIOUS DISEASES
1996; 173 (4): 849-856
Initiation of antiretroviral monotherapy early in the course of infection with human immunodeficiency virus may result in a temporary slowing in the rate of disease progression; however, little is known about the virologic effects of early therapy. Virus load was measured in peripheral blood and lymph nodes from 16 antiretroviral-naive patients with a mean CD4 T lymphocyte count of 659 cells/microliter at baseline and after 8 weeks of either no treatment or zidovudine therapy. CD4 T lymphocyte counts and all virologic parameters examined remained unchanged regardless of zidovudine treatment status. Histopathology and virus distribution within lymph nodes remained constant between baseline and week 8 in each patient, indicating that the virologic and histologic parameters examined in a single lymph node are representative of a systemic process. Early antiretroviral monotherapy with zidovudine had no effect on virologic parameters in this group of patients with relatively high CD4 T lymphocyte counts and low measures of virus load at baseline.
View details for Web of Science ID A1996UB27400009
View details for PubMedID 8603962
- Quantitative relationship between platelet count and plasma virion HIV RNA AIDS 1996; 10 (2): 232-233
SAFETY, PHARMACOKINETICS, AND ANTIVIRAL RESPONSE OF CD4-IMMUNOGLOBULIN-G BY INTRAVENOUS BOLUS IN AIDS AND AIDS-RELATED COMPLEX
JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES
1995; 10 (2): 150-156
To assess the safety, pharmacokinetics, and antiviral effects of intravenous recombinant CD4 immunoglobulin G (CD4-IgG), a 12-week Phase One study with an optional maintenance phase was performed. Twenty-two subjects with advanced human immunodeficiency virus (HIV) infection were enrolled; 15 subjects completed the initial 12 weeks. CD4-IgG doses were 30, 100, or 300 micrograms/kg weekly; 1,000 micrograms/kg once, twice, or three times per week; or 3,000 micrograms/kg twice weekly. Serum concentrations of CD4-IgG increased linearly with dose, with average peak serum concentrations of 22 micrograms/ml with 1,000 micrograms/kg. CD4-IgG was well tolerated; one patient had self-limited tachycardia and flushing associated with CD4-IgG therapy. No changes were seen in CD4 cell counts, hematologic or coagulation studies, serum chemistries, HIV p24 antigen titers, or plasma HIV titers. No subject developed anti-CD4 antibodies. HIV isolates from five patients had IC90 values that were higher than the peak concentrations of CD4-IgG achieved in those patients. Additional studies that achieve higher CD4-IgG concentrations are necessary to evaluate the antiviral activity of this compound.
View details for Web of Science ID A1995RW33000006
View details for PubMedID 7552478
NONISOTOPIC HYBRIDIZATION ASSAY FOR DETERMINATION OF RELATIVE AMOUNTS OF GENOTYPIC HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 ZIDOVUDINE RESISTANCE
JOURNAL OF CLINICAL MICROBIOLOGY
1995; 33 (10): 2777-2780
A nonisotopic hybridization assay for human immunodeficiency virus genotypic zidovudine resistance determination is described. Biotinylated PCR product was hybridized with enzyme-labeled probes for wild-type or resistant mutant sequences and detected colorimetrically or chemiluminescently in a microplate format. Changes in mutant-to-wild-type ratios allow for the monitoring of longitudinal patient samples.
View details for Web of Science ID A1995RV56500050
View details for PubMedID 8567926
DECREASED HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 PLASMA VIREMIA DURING ANTIRETROVIRAL THERAPY REFLECTS DOWN-REGULATION OF VIRAL REPLICATION IN LYMPHOID-TISSUE
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1995; 92 (13): 6017-6021
Although several immunologic and virologic markers measured in peripheral blood are useful for predicting accelerated progression of human immunodeficiency virus (HIV) disease, their validity for evaluating the response to antiretroviral therapy and their ability to accurately reflect changes in lymphoid organs remain unclear. In the present study, changes in certain virologic markers have been analyzed in peripheral blood and lymphoid tissue during antiretroviral therapy. Sixteen HIV-infected individuals who were receiving antiretroviral therapy with zidovudine for > or = 6 months were randomly assigned either to continue on zidovudine alone or to add didanosine for 8 weeks. Lymph node biopsies were performed at baseline and after 8 weeks. Viral burden (i.e., HIV DNA copies per 10(6) mononuclear cells) and virus replication in mononuclear cells isolated from peripheral blood and lymph node and plasma viremia were determined by semiquantitative polymerase chain reaction assays. Virologic and immunologic markers remained unchanged in peripheral blood and lymph node of patients who continued on zidovudine alone. In contrast, a decrease in virus replication in lymph nodes was observed in four of six patients who added didanosine to their regimen, and this was associated with a decrease in plasma viremia. These results indicate that decreases in plasma viremia detected during antiretroviral therapy reflect downregulation of virus replication in lymphoid tissue.
View details for Web of Science ID A1995RF05000054
View details for PubMedID 7597072
DETERMINATION OF HUMAN-IMMUNODEFICIENCY-VIRUS RNA IN PLASMA AND CELLULAR VIRAL-DNA GENOTYPIC ZIDOVUDINE RESISTANCE AND VIRAL LOAD DURING ZIDOVUDINE-DIDANOSINE COMBINATION THERAPY
JOURNAL OF VIROLOGY
1995; 69 (6): 3510-3516
Eleven human immunodeficiency virus (HIV)-infected subjects on long-term zidovudine (ZDV) therapy had didanosine (ddI) added to their antiretroviral regimen. HIV RNA in plasma was quantitated by branched-DNA signal amplification assay. Peripheral blood mononuclear cell (PBMC) HIV viral DNA was quantitated by PCR. The relative amounts of wild-type (WT) sequence, ddI resistance-associated codon changes (reverse transcriptase [RT] gene codon 65 K-->R [RT K65R], RT 174V, RT I135K/T/V, and RT M184I/V), and ZDV resistance-associated codon change (RT T215Y/F) from HIV RNA in plasma and RT T215Y/F from PBMC viral DNA were determined by differential hybridization of PCR products from 10 of 11 subjects. All subjects had evidence of RT T215Y/F mutation in both RNA in plasma and PBMC DNA at baseline. Subjects with a mixture of WT and RT T215Y/F HIV RNA in plasma at baseline demonstrated a decline in RNA levels in plasma after the addition of ddI. However, after 6 months of ZDV-ddI therapy, WT HIV RNA in plasma was undetectable in all subjects who had demonstrated a mixture at baseline. Subjects with only RT T215Y/F RNA present in plasma at baseline remained so and demonstrated no decline in RNA levels in plasma. In all subjects, no significant changes in PBMC DNA viral load and RT T215Y/F or WT levels were seen. HIV RNA in plasma demonstrated a significantly higher RT T215Y/F mutant/WT ratio than that of PBMC viral DNA, both at baseline and after ZDV-ddI combination therapy in all subjects. No subjects developed mutations associated with ddI resistance at codons 65, 74, 135, and 184 during this study. This study suggests that determination of relative amounts of RT T215Y/F and WT species from HIV RNA in plasma at baseline may be predictive of virologic response during ZDV-ddI combination therapy.
View details for Web of Science ID A1995QX93100030
View details for PubMedID 7745698
COMPARATIVE STABILITIES OF QUANTITATIVE HUMAN-IMMUNODEFICIENCY-VIRUS RNA IN PLASMA FROM SAMPLES COLLECTED IN VACUTAINER CPT, VACUTAINER PPT, AND STANDARD VACUTAINER TUBES
JOURNAL OF CLINICAL MICROBIOLOGY
1995; 33 (6): 1562-1566
This study compared the levels of human immunodeficiency virus (HIV) virion RNA in plasma from whole blood collected in VACUTAINER CPT (cell preparation tube), VACUTAINER PPT (plasma preparation tube), VACUTAINER SST (serum separation tube), and standard VACUTAINER tubes with sodium heparin, acid citrate dextrose, sodium citrate, and potassium EDTA used as anticoagulants. Quantitative plasma HIV RNA levels were measured by branched-DNA signal amplification. Blood from all tubes was either processed within 1 to 3 h after collection or stored at room temperature or at 4 degrees C for analysis at 6 to 8 and 30 h postdraw. Immediately separated plasma from sodium citrate CPT tubes held at 4 degrees C maintained better stability of HIV RNA equivalents than whole blood held at room temperature or 4 degrees C. The highest number of HIV RNA equivalents was seen with EDTA VACUTAINER tubes. HIV RNA equivalents in all types of plasma were significantly higher than in SST tubes. Although a decline in HIV RNA equivalents was seen in all collection devices after 30 h, a significantly greater decline in plasma HIV RNA equivalents occurred in acid citrate dextrose VACUTAINER tubes than in citrate CPT, PPT, and standard EDTA VACUTAINER tubes. In order to minimize the variability of quantitative HIV RNA test results, our data suggest that samples collected for a particular assay should be processed at the same time postdraw using a particular tube type throughout a given study.
View details for Web of Science ID A1995QZ72300026
View details for PubMedID 7650187
HIV viral load quantification, HIV resistance, and antiretroviral therapy.
AIDS clinical review
We are moving rapidly beyond a "black box" understanding of the pathogenesis of HIV. The sites of virus replication, the molecular regulation of virus production in the host, and the dynamics between productive virus infection and immunological and clinical events are areas of intense study using powerful new tools. The quantitation of virus load and genetic characterization of replicating virus has important implications for the development and evaluation of drugs and treatment strategies for HIV. As new compounds are introduced, their ability to reduce virus load in vivo has become a primary consideration in the decision to initiate large efficacy trials and may soon be used, in combination with other markers, in the licensing of new agents. In parallel, rapid molecular evaluation of virus from patients, targeting those who break through drug-induced suppression, provides an explanation for the failure of drugs to sustain an effect on virus load. This approach has compressed the process of drug evaluation and set the stage for the evaluation of complex combinations and sequences of drugs to maintain suppression of virus and prevent the development of drug resistance. The most controversial question for the next few years is whether the measurement of virus load or detection of drug resistance can be incorporated into the practice of medicine and the management of individual patients. There is evidence that changes in virus load are the most proximate markers of drug response and that detection of resistance mutations can predict clinical and immunological decline. However, the window of time between a change in load or the development of drug resistance and a decline in CD4 cells is relatively short. With dideoxynucleoside therapies, a CD4 cell decline follows a rise in virus load or development of resistance within 3-6 months. In early studies with protease inhibitors and nonnucleoside reverse transcriptase inhibitors, the development of resistance and a return to baseline of virus load may occur within 2-3 months, mirrored by a fall in CD4 cells. The challenge to investigators is how to best use these new tools to determine whether changes or additions in therapy, initiated on the basis of virological measurements, result in more effective management of disease.
View details for PubMedID 7488557
DEFICIENCY IN ANTIBODY-RESPONSE TO HUMAN CYTOMEGALOVIRUS GLYCOPROTEIN GH IN HUMAN IMMUNODEFICIENCY VIRUS-TREATED PATIENTS AT RISK FOR CYTOMEGALOVIRUS RETINITIS
JOURNAL OF INFECTIOUS DISEASES
1994; 170 (3): 673-677
Human immunodeficiency virus (HIV)-infected patients at risk for symptomatic human cytomegalovirus (CMV) infection were studied for serum antibody to CMV glycoproteins gH and gB. Antibody titers to gB in HIV-seropositive patients, irrespective of CD4 cell counts or presence of CMV retinitis, were significantly higher than titers in HIV-seronegative, CMV-seropositive patients but were comparable to titers detected in HIV-seronegative patients with CMV mononucleosis. In contrast, antibody to gH was rarely detected in HIV-seropositive patients with CD4 cell counts > 100/mm3 compared with patients with counts > 100/mm3. The inability to detect gH antibody at a time of high risk for symptomatic CMV retinitis suggests that immune intervention with either gH-specific vaccine or passive immunotherapy may benefit HIV-infected persons at risk for symptomatic CMV disease.
View details for Web of Science ID A1994PE26500026
View details for PubMedID 7915750
STABILITIES OF QUANTITATIVE PLASMA CULTURE FOR HUMAN-IMMUNODEFICIENCY-VIRUS, RNA, AND P24 ANTIGEN FROM SAMPLES COLLECTED IN VACUTAINER CPT AND STANDARD VACUTAINER TUBES
JOURNAL OF CLINICAL MICROBIOLOGY
1994; 32 (9): 2212-2215
We evaluated the stability of human immunodeficiency virus (HIV) load markers from blood samples collected in VACUTAINER CPT or standard VACUTAINER brand tubes using sodium heparin or sodium citrate as anticoagulants. Quantitative plasma culture and p24 antigen concentrations were determined, and HIV RNA levels in plasma were measured by both reverse transcription-PCR-enzyme-linked immunosorbent assay (RT-PCR-ELISA) and branched DNA methods. All tubes were stored at room temperature for analysis at 2, 24, 48, and 72 h after the blood samples were drawn. No difference was seen between tube types with respect to the HIV titer in plasma or the positivity rate for all samples that demonstrated a fall in titer over time. Unbound p24 antigen levels in plasma decreased during the initial 48-h period in both tube types. Immune complex-dissociated p24 antigen levels decreased in CPT tubes but not in standard VACUTAINER tubes. The HIV RNA copy number in plasma measured by RT-PCR-ELISA was stable in most subjects and was significantly higher in CPT tubes than in standard VACUTAINER tubes at 24 and 72 h after the blood samples were drawn. The branched DNA probe assay detected a significant decline in HIV RNA equivalent in plasma over 72 h in both collection tubes, the decline being more dramatic in the standard VACUTAINER tube than the CPT tube. Overall, interday variability suggests that samples collected for a particular assay should be processed at the same time after blood is drawn and that a particular tube type be used throughout a given study.
View details for Web of Science ID A1994PB54100032
View details for PubMedID 7814549
CLINICAL-APPLICATION OF REVERSE TRANSCRIPTION-POLYMERASE CHAIN-REACTION FOR HIV-INFECTION
CLINICS IN LABORATORY MEDICINE
1994; 14 (2): 335-349
This article describes the current knowledge of the various RT-PCR assays and their clinical application in HIV disease. The importance of assay precision and sample handling is emphasized. A review of quantification techniques is also presented. Finally, the relevant literature describing the application of RT-PCR for both virion RNA in plasma and cellular mRNA is reviewed.
View details for Web of Science ID A1994PD13100009
View details for PubMedID 7523019
ANTIBIOTIC-ASSOCIATED PSEUDOMEMBRANOUS ENTERITIS DUE TO CLOSTRIDIUM-DIFFICILE
CLINICAL INFECTIOUS DISEASES
1994; 18 (6): 982-984
Although pseudomembranous colitis is relatively common following antibiotic exposure, there have been few reported cases of pseudomembrane formation involving the small intestine. Herein we report a case of pseudomembranous enteritis of the small and large intestine that occurred after antibiotic exposure. The etiologic organism appears to be Clostridium difficile, as evidenced by the characteristic pseudomembranous lesions and a positive ELISA for toxin A in an ileal tissue specimen.
View details for Web of Science ID A1994NQ82600023
View details for PubMedID 8086563
- THE USE OF PENTOXIFYLLINE ALONE IN HIV-INFECTED PATIENTS JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY 1994; 7 (5): 519-521
DIURNAL AND SHORT-TERM STABILITY OF HIV VIRUS LOAD AS MEASURED BY GENE AMPLIFICATION
JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES
1994; 7 (4): 363-368
To determine whether human immunodeficiency virus (HIV) viral load has short term stability, eight clinically stable subjects infected with HIV and having CD4 counts ranging between 10-600/mm3, had blood samples taken at 0800 and 1700 on 3 consecutive days and then weekly at 0800 for 1 month (8-10 observations/subject). Plasma HIV RNA, peripheral blood mononuclear cell (PBMC) proviral DNA, serum p24 antigen levels, and mononuclear cell subsets were measured at each time point. Mean plasma HIV RNA, PBMC HIV DNA, and p24 antigen [both regular and immune complex dissociated (ICD)] levels did not change significantly between mornings and afternoons or on successive days or weeks. CD4+, CD8+, and CD56+ number demonstrated a diurnal variation in those subjects with > 200 CD4 cells/mm3. We conclude that HIV viral load demonstrates short-term stability in clinically stable subjects. This stability has important implications for monitoring HIV disease progression or antiretroviral therapy.
View details for Web of Science ID A1994NC77500007
View details for PubMedID 7907661
DETECTION OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 IN SEMEN - EFFECTS OF DISEASE STAGE AND NUCLEOSIDE THERAPY
JOURNAL OF INFECTIOUS DISEASES
1993; 167 (4): 798-802
The effects of clinical stage of infection and antiviral therapy on the detection of human immunodeficiency virus type 1 (HIV-1) nucleic acids in semen were investigated by the polymerase chain reaction. HIV-1 was detected in 45 (87%) of 52 semen specimens from 29 (81%) of 36 men. Seventeen (77%) of 22 stage II or III subjects and 12 (86%) of 14 stage IV subjects had positive specimens. The CD4+ lymphocyte count was not significantly different comparing subjects with positive and negative semen. Moreover, 6 (67%) of 9 untreated men had positive specimens compared with 23 (85%) of 27 men treated with zidovudine, 2',3'-dideoxyinosine, or both for a mean of 20 months. Thus, the detection of HIV-1 in semen was independent of both stage of infection and long-term treatment. In a semiquantitative analysis of 6 men followed for 8 weeks after the start of nucleoside therapy, a decrease in HIV-1 RNA in seminal plasma was demonstrated in 2.
View details for Web of Science ID A1993KU08600002
View details for PubMedID 8450243
MEASUREMENT OF HIV VIRUS LOAD AND GENOTYPIC RESISTANCE BY GENE AMPLIFICATION IN ASYMPTOMATIC SUBJECTS TREATED WITH COMBINATION THERAPY
JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES
1993; 6 (4): 366-369
Quantification of viral load in HIV disease has become increasingly important as a marker of antiviral efficacy. We applied gene amplification techniques in vivo to asses antiretroviral activity of combination therapy. Five HIV-infected subjects, four of whom were drug naive, were administered combination therapy with zidovudine (ZDV) and didanosine (ddI). Plasma and peripheral blood mononuclear cells (PBMC) were obtained twice at baseline and then at 1, 3, 6, 9, and 12 months after the initiation of therapy. Results show that plasma HIV RNA copy number fell from 2,170 +/- 660/ml to undetectable at 1 month, with continued suppression at 12 months. HIV proviral DNA copy number decreased from 3.9 to 3.0 log10/10(6) CD4+ T cells at 12 months. Cell dilution cultures were positive in 4 of 5 subjects at baseline and in only 1 of 5 after 12 months. CD4+ T-cell count increased from 390 +/- 30/mm3 pretherapy, to 505 +/- 66/mm3 after 6 months of therapy, but returned to baseline levels after 12 months of therapy. No mutations were detected from PBMC DNA for codon 215 and 74 in the HIV pol gene from the drug-naive subjects. These findings suggest that gene amplification techniques can be used to study changes in viral load or genotype and can be applied in real time to samples from patients involved in clinical trials.
View details for Web of Science ID A1993KU22100007
View details for PubMedID 8095981
- Peripheral blood mononuclear cell human immunodeficiency virus type 1 proviral DNA quantification by polymerase chain reaction: relationship to immunodeficiency and drug effect Journal of Clinical Microbiology 1993; 31 (10): 2692-96
Quantitative RNA and DNA gene amplification can rapidly monitor HIV infection and antiviral activity in cell cultures.
PCR methods and applications
1992; 1 (4): 257-262
We have developed a quantitative gene amplification procedure to assess the replication of human immunodeficiency virus (HIV) in cell cultures and evaluate the effect of drugs on viral replication. Increases in HIV gag RNA and DNA in phytohemagglutinin-stimulated normal peri-pheral blood mononuclear cells (PBMC) infected with HIV at very low multiplicity of infection paralleled the production of HIV p24 antigen in culture supernatants. Quantitative gene amplification was able to monitor the accumulation of viral nucleic acids in control cultures and demonstrate the effect of various concentrations of azidothymidine (AZT) on the replication of both AZT-sensitive and -resistant strains of HIV. The sensitivity of patient-derived virus strains to AZT could also be successfully measured by these procedures. The results of our studies suggest that quantitative measurement of HIV gag RNA and DNA can be used to monitor the kinetics of viral replication, antiviral activity, viral drug resistance, and mechanism of drug action.
View details for PubMedID 1477661
- THE SULFONE SYNDROME IN A PATIENT RECEIVING DAPSONE PROPHYLAXIS FOR PNEUMOCYSTIS-CARINII PNEUMONIA WESTERN JOURNAL OF MEDICINE 1992; 156 (3): 303-306
CORRELATION OF MORPHOLOGICAL DIAGNOSIS OF PNEUMOCYSTIS-CARINII WITH THE PRESENCE OF PNEUMOCYSTIS DNA AMPLIFIED BY THE POLYMERASE CHAIN-REACTION
1992; 5 (2): 103-106
We compared the presence of P. carinii in clinical specimens as detected by standard cytomorphologic techniques with amplification of P. carinii-specific DNA by the polymerase chain reaction (PCR). Results correlated in 33 of 37 instances (89%): nine specimens were positive by both PCR and morphology; 24 specimens were negative by both techniques. Two specimens from one patient were obtained 3 days apart. The first specimen was both cytologically and PCR negative, while the second specimen was both cytologically and PCR positive for P. carinii. At least in some instances, therefore, PCR is no more sensitive than morphology, and other factors such as specimen adequacy are more important. Twelve of the 24 negative specimens were from patients with prior histories of P. carinii pneumonia, suggesting that recurrent disease may be from reacquisition of organisms in previously exposed individuals, rather than reactivation of latent organisms. Discrepant results included three morphologically negative specimens that were positive by PCR. It remains to be determined whether the increased sensitivity of PCR in these cases is real or artifactual. One morphologically positive specimen was negative by PCR. Polymerase chain reaction correlates well with cytomorphologic diagnosis of P. carinii pneumonia and may be a valuable diagnostic and epidemiologic tool.
View details for Web of Science ID A1992HJ85500003
View details for PubMedID 1374186
PLASMA VIREMIA IN HUMAN-IMMUNODEFICIENCY-VIRUS INFECTION - RELATIONSHIP TO STAGE OF DISEASE AND ANTIVIRAL TREATMENT
JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY
1992; 5 (2): 107-112
Quantitative culture of human immunodeficiency virus (HIV) was performed on 121 plasma samples from 76 HIV-infected individuals to determine the sensitivity of the assay at different stages of disease and to measure the effect of antiviral therapy on plasma viremia. Plasma virus was detected in 49 of 76 (64%) of patients, primarily those with AIDS and AIDS-related complex (36 of 38) versus asymptomatic subjects (13 of 38) (p less than 0.001, chi 2). Similarly, plasma cultures were more often positive in patients with less than 250 CD4+ T cells per microliter (38 of 40) than in those with greater than 250 CD4+ T cells per microliter (11 of 36) (p less than 0.001, chi 2). Plasma virus cultures were also more likely to be positive in patients with detectable serum p24 antigen (24 of 26) than in those without detectable p24 antigen (25 of 50) (p = 0.0023, chi 2). An effect of zidovudine (ZDV) treatment on plasma viremia was seen in a comparison of treated and untreated patients with less than 250 CD4+ T cells per microliter. Geometric mean titers of plasma viremia from 16 patients treated with ZDV for more than 3 months were significantly lower than titers from 24 untreated patients (10(1.3) versus 10(2.1), p less than 0.05, Student's t test. A comparison of pre- and posttherapy titers in 33 patients receiving antiviral treatment showed that plasma virus was not detectable at either time in 17 patients; there was a fall in plasma virus titer in 12; and titers were unchanged or increased in 4. In patients with advanced disease, plasma viremia is a potential marker of antiviral drug activity.
View details for Web of Science ID A1992GZ90200001
View details for PubMedID 1732501
DETECTION AND QUANTIFICATION OF GENE AMPLIFICATION PRODUCTS BY A NONISOTOPIC AUTOMATED-SYSTEM
1992; 12 (1): 36-?
We describe in this report the ability to determine human immunodeficiency virus proviral copy number by an automated nonisotopic method. Our system utilizes a FACStarPLUS cell sorter, the GeneAmp PCR System 9600 and a Biomek 1000 robotic workstation. Linking these three machines allows cell populations to be sorted and the DNA amplified and quantitated with minimal technical effort. We have developed this system to quantitate proviral DNA copy number in sorted subpopulations of peripheral blood cells in one day.
View details for Web of Science ID A1992GZ18400006
View details for PubMedID 1531177
DECREASE IN HIV PROVIRUS IN PERIPHERAL-BLOOD MONONUCLEAR-CELLS DURING ZIDOVUDINE AND HUMAN RIL-2 ADMINISTRATION
JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY
1992; 5 (1): 52-59
Quantification of human immunodeficiency virus (HIV) proviral DNA in peripheral blood mononuclear cells (PBMC) was performed in 13 HIV-seropositive asymptomatic individuals during 10-24 months by polymerase chain reaction amplification of multiple half-log dilutions of cellular DNA. At enrollment, subjects had a geometric mean titer of 100 copies of HIV provirus per 10(6) PBMC (mean +/- SD, 2 +/- 0.9 log10). In four untreated individuals there was no significant change in provirus levels during a mean period of 13.3 months. In eight patients treated with zidovudine (ZDV) and human recombinant interleukin 2 (rIL-2), HIV provirus copies declined to 13 per 10(6) cells (1.1 +/- 0.8 log10) at the end of the first course of ZDV and rIL-2 at week 20 (p less than 0.01), and to 40 per 10(6) cells (1.6 +/- 0.9 log10) after 12 months of treatment (p less than 0.04). Subsequent courses, which included 12 weeks of ZDV alone or 4 weeks of IL-2 alone, did not significantly change the already depressed provirus copy numbers. Proviral copy number also remained depressed during drug-free "washout periods" between courses. Finally, we observed a return to a geometric mean of 400 copies per 10(6) cells (2.6 +/- 0.3 log10) a mean of 7.9 months after discontinuation of therapy. Measurement of changes in HIV provirus should provide a direct marker for defining antiviral activity of drugs, biologics, and combination therapy.
View details for Web of Science ID A1992GW91300009
View details for PubMedID 1738087
Quantitative virological measures of antiretroviral therapy.
AIDS clinical review
View details for PubMedID 1376615
REDUCTION IN PLASMA HUMAN-IMMUNODEFICIENCY-VIRUS RIBONUCLEIC-ACID AFTER DIDEOXYNUCLEOSIDE THERAPY AS DETERMINED BY THE POLYMERASE CHAIN-REACTION
JOURNAL OF CLINICAL INVESTIGATION
1991; 88 (5): 1755-1759
Cell-free HIV RNA in plasma was detected and quantitated after antiviral therapy by the polymerase chain reaction. RNA was extracted from plasma, reverse transcribed to cDNA, amplified by polymerase chain reaction, and quantitated by absorbance based on an enzyme-linked affinity assay. 72 HIV antibody-positive subjects had one plasma sample taken. 39 who were not receiving antiretroviral therapy at the time had a mean plasma HIV RNA copy number of 690 +/- 360 (mean +/- SEM) per 200 microliters of plasma, while 33 subjects who had been receiving zidovudine therapy for a minimum of 3 mo had a mean copy number of 134 +/- 219 (P less than 0.05). 27 additional HIV antibody-positive patients had two plasma samples taken before and 1 mo after initiating dideoxynucleoside therapy. Plasma HIV RNA copy number fell from 540 +/- 175 to 77 +/- 35 (P less than 0.05). Finally, nine of these subjects had two baseline samples obtained before initiating therapy and two posttreatment samples 1 and 2 mo after therapy was begun. Mean plasma RNA copy number declined from 794 +/- 274 to less than 40 (below the lower limit of sensitivity) after 1 mo of therapy, with suppression maintained after 2 mo of therapy. These results suggest that gene amplification can be used to detect and quantitate changes in plasma HIV RNA after dideoxynucleoside therapy. Plasma HIV polymerase chain reaction may be a more sensitive marker to monitor antiviral therapy, particularly in asymptomatic patients where measurement of p24 antigen or quantitative plasma cultures are negative.
View details for Web of Science ID A1991GN72700044
View details for PubMedID 1682345
DETECTION OF HUMAN-IMMUNODEFICIENCY-VIRUS DNA AND RNA IN SEMEN BY THE POLYMERASE CHAIN-REACTION
JOURNAL OF INFECTIOUS DISEASES
1991; 164 (4): 769-772
Peripheral blood mononuclear cells (PBMC) and semen of 23 men infected with human immunodeficiency virus (HIV) were examined for the presence of HIV DNA and RNA using the polymerase chain reaction (PCR) and a nonisotopic detection assay. None of the men was receiving antiretroviral therapy at the time of collection. Semen samples were separated into cell-free seminal fluid, nonspermatozoal mononuclear cells (NSMC), and spermatozoa. All of the PBMC samples, 17 (74%) of 23 NSMC samples, and none of the spermatozoal samples were positive for HIV gag gene DNA. Of 23 cell-free seminal fluid samples, 15 (65%) were positive for HIV gag gene RNA by PCR. Cell-free HIV RNA was more likely to be present in the semen of men with less than 400 than in those with greater than or equal to 400 cells/mm3 (P less than .04) and was present in all patient with p24 antigen in serum. The presence of HIV DNA in NSMC samples was not related to CD4 cell count, disease status, or the presence of p24 antigen in the serum. This study shows that HIV nucleic acid can be detected by PCR in either the cell-free seminal fluid or NSMC of 87% of semen samples but not in the DNA of spermatozoa from HIV-infected men.
View details for Web of Science ID A1991GF80500022
View details for PubMedID 1680138
INHIBITION OF HUMAN-IMMUNODEFICIENCY-VIRUS GENE AMPLIFICATION BY HEPARIN
JOURNAL OF CLINICAL MICROBIOLOGY
1991; 29 (4): 676-679
Gene amplification of virus-specific sequences is widely used as a method to detect or confirm human immunodeficiency virus (HIV) infection. In this study we used an enzyme-linked affinity assay to quantify polymerase chain reaction products from whole blood, plasma, and separated mononuclear cells collected in the presence of four common anticoagulants: acid citrate dextrose, sodium EDTA, potassium oxalate, and sodium heparin. Attenuation of the product signal was observed after amplification of nucleic acid extraction from whole blood, washed mononuclear cells, and plasma from specimens collected in sodium heparin. These inhibitory effects on gene amplification could be reversed with heparinase. The addition of as little as 0.05 U of heparin completely inhibited amplification of an HLA-DQa sequence from placental DNA. We conclude that heparin can cause attenuation or inhibition of gene amplification. Acid citrate dextrose and EDTA, which lack inhibitory activity, are the most appropriate anticoagulants for clinical blood samples when polymerase chain reaction amplification is anticipated.
View details for Web of Science ID A1991FC91900003
View details for PubMedID 1909709
DETECTION AND QUANTIFICATION OF HUMAN-IMMUNODEFICIENCY-VIRUS RNA IN PATIENT SERUM BY USE OF THE POLYMERASE CHAIN-REACTION
JOURNAL OF INFECTIOUS DISEASES
1991; 163 (4): 862-866
Human immunodeficiency virus (HIV) RNA was detected and quantified in the serum of HIV-seropositive individuals using the polymerase chain reaction (PCR) and a nonisotopic enzyme-linked affinity assay. Of 55 HIV-infected patients who were not receiving therapy, serum HIV RNA was detected in 9 of 19 who were asymptomatic, 11 of 16 with AIDS-related complex (ARC), and 18 of 20 with AIDS, with copy numbers ranging from 10(2) to greater than or equal to 5 x 10(4) 200 microliters of serum based on a relationship between absorbance and known copy number of gag gene RNA. Linear regression analysis demonstrated a correlation between infectious titer in 42 patient sera cocultured with donor peripheral blood mononuclear cells (PBMC) and PCR product absorbance (r = .70, P less than .01). Serum HIV RNA detected by PCR also correlated with serum p24 antigen positivity, CD4 counts less than 400/mm3, and the presence of HIV-related symptoms or disease. Quantification of infectious HIV RNA in cell-free serum by PCR may be useful as a marker for for disease progression or in monitoring antiviral therapy.
View details for Web of Science ID A1991FD93900031
View details for PubMedID 2010639
CEREBRAL SPARGANOSIS - CASE-REPORT AND REVIEW
REVIEWS OF INFECTIOUS DISEASES
1991; 13 (1): 155-159
Sparganosis is a rare infection caused by a tapeworm larva from the genus Spirometra. A 21-year-old Indian man presented with an 18-month history of episodic confusion followed by a grand mal seizure. Computed tomography and magnetic resonance imaging of the brain confirmed the presence of a lesion of the left occipital lobe. Subsequent stereotactic biopsy revealed a plerocercoid larva or sparganum. Surgical resection resulted in cure. This case prompted a review of the literature on central nervous system sparganosis. Altogether, 17 other cases of primary cerebral sparganosis have been reported previously. Seizures, headache, and focal neurologic signs are common at presentation. Neuroradiologic imaging is sensitive but not specific for the identification of lesions. Enzyme-linked immunosorbent assay of cerebrospinal fluid or serum may be diagnostically helpful. However, the diagnosis is generally made after surgical resection, which is usually curative.
View details for Web of Science ID A1991EU52000025
View details for PubMedID 2017616
CORRELATION BETWEEN HUMAN-IMMUNODEFICIENCY-VIRUS (HIV) LOAD, STAGE OF DISEASE AND DIDEOXY DRUG ADMINISTRATION USING QUANTITATIVE RNA AND DNA-POLYMERASE CHAIN-REACTION (PCR) AND VIREMIA MEASUREMENTS
VIRAL QUANTITATION IN HIV INFECTION
View details for Web of Science ID A1991BV41D00017
Recombinant soluble CD4 therapy in patients with the acquired immunodeficiency syndrome (AIDS) and AIDS-related complex. A phase I-II escalating dosage trial.
Annals of internal medicine
1990; 112 (4): 247-253
To study the safety and pharmacokinetics and to derive preliminary evidence on surrogate indicators of efficacy of recombinant soluble CD4 (rsCD4) in patients with the acquired immunodeficiency syndrome (AIDS) and advanced AIDS-related complex.Open label, escalating dosage, phase I-II tolerance trial.Massachusetts General Hospital, Cedars-Sinai Medical Center, and Stanford University Medical School, three tertiary care institutions and members of the National Institute of Allergy and Infectious Diseases AIDS Clinical Trials Group. INSTRUCTIONS: Cohorts of 3 to 11 patients received rsCD4 by intravenous infusion or intramuscular injection in dosages of up to 30 mg per day for 28 days. MEASUREMENTS andRecombinant soluble CD4 was tolerated by these patients with no significant clinical or immunologic toxicities. Serum levels of rsCD4 in patients receiving doses of 9 or 30 mg per day administered intramuscularly were in the range of rsCD4 concentrations required to inhibit replication of human immunodeficiency virus 1 (HIV-1) in vitro. A decline in serum HIV-1 p24 antigen was seen in patients receiving 30 mg of rsCD4 daily, but no such changes were noted at lower dosages.Recombinant soluble CD4 is well tolerated by patients with AIDS or advanced AIDS-related complex. Our study has also provided preliminary evidence of antiviral activity of rsCD4 in vivo. Our data suggest that further trials of receptor-based therapies against HIV-1 are warranted.
View details for PubMedID 2297203
FULMINANT KAPOSIS-SARCOMA COMPLICATING LONG-TERM CORTICOSTEROID-THERAPY
AMERICAN JOURNAL OF MEDICINE
1987; 83 (4): 787-789
Cutaneous Kaposi's sarcoma occurs rarely in patients receiving long-term corticosteroid therapy. The case of a rapidly progressive form of Kaposi's sarcoma occurring in a 29-year-old Palestinian woman with steroid-dependent Crohn's disease and familial Mediterranean fever is reported. Despite an extensive transfusion history, serologic and virologic studies failed to demonstrate exposure to the human immunodeficiency virus. Serologic and virologic evidence of concomitant cytomegalovirus infection, however, suggests possible pathogenic features similar to the acquired immunodeficiency syndrome-related form of Kaposi's sarcoma.
View details for Web of Science ID A1987K590600029
View details for PubMedID 2823601
IL28B POLYMORPHISM IS NOT ASSOCIATED WITH HCV PROTEASE DIVERSITY IN HIV/HCV-COINFECTED PATIENTS TREATED WITH AN INTERFERON-BASED REGIMEN
WILEY-BLACKWELL. 2011: 815A-815A
View details for Web of Science ID 000295578003193
Evolution of genotypic resistance algorithms and their impact on the interpretation of clinical trials: an OPTIMA trial substudy
INT MEDICAL PRESS LTD. 2006: S184-S184
View details for Web of Science ID 000239984700184
The impact of active herpes simplex virus infection on human immunodeficiency virus load
OXFORD UNIV PRESS INC. 1997: 766-770
The effect of a concurrent herpes simplex virus (HSV) infection on human immunodeficiency virus type 1 (HIV-1) load was evaluated. Sixteen subjects were identified with an active HSV infection and had pre-outbreak, acute-phase, and post-outbreak plasma (n = 16) and peripheral blood mononuclear cell (PBMC) (n = 8) samples for evaluation. All subjects were treated for an acute HSV outbreak with acyclovir for 10 days, followed by chronic prophylaxis. HIV-1 plasma RNA levels were determined by branched DNA, and intracellular HIV gag mRNA copy numbers were determined by quantitative reverse transcriptase-polymerase chain reaction ELISA. Plasma virus load increased a median of 3.4-fold during the acute outbreak (range, 0- to 10-fold; P = .002), while post-outbreak levels (30-45 days after the appearance of lesions) remained above pre-outbreak, baseline levels in some subjects. Intracellular HIV gag mRNA increased during the outbreak as well. Thus, an acute HSV episode can result in increased HIV transcription and plasma virus load.
View details for Web of Science ID A1997XT81900032
View details for PubMedID 9291329
PERFORMANCE-CHARACTERISTICS FOR THE QUANTITATION OF PLASMA HIV-1 RNA USING BRANCHED DNA SIGNAL AMPLIFICATION TECHNOLOGY
LIPPINCOTT WILLIAMS & WILKINS. 1995: S35-S44
Highly sensitive assays that quantitate human immunodeficiency virus type 1 (HIV-1) RNA may be valuable for clinical research and the treatment of HIV-1-infected patients. In this study we evaluated the reproducibility and accuracy of the first-generation branched DNA (bDNA-1.0) signal amplification assay under conditions that are relevant to routine use in a clinical context. We show that the bDNA-1.0 assay was able to discern two- to three-fold changes in plasma HIV-1 RNA levels as significant. Reverse transcription coupled to polymerase chain reaction (RT-PCR) was less reproducible and required a 3.7- to 5.8-fold change in plasma HIV-1 RNA levels to be statistically significant. The accuracy of the bDNA-1.0 assay in RNA quantitation was not affected by HIV-1 genotypic variation or by the presence of hemoglobin, bilirubin, lipemia, or any of a dozen therapeutic drugs. Using the bDNA-1.0 assay, we show that HIV-1 RNA levels in plasma specimens were stable when stored at -80 degrees C and were able to withstand at least three freeze-thaw cycles without significant loss. We also examined the performance of an ultrasensitive bDNA assay with improvements to the signal amplification technology. The ultrasensitive bDNA assay displayed a quantitation limit of approximately 500 RNA Eq/ml, yet maintained a dynamic quantitation range up to 1.6 x 10(6) RNA Eq/ml. Like the bDNA-1.0 assay, the ultrasensitive bDNA assay was not affected by HIV-1 genotype variability.
View details for Web of Science ID A1995TD18600006
View details for PubMedID 7552511