- Cystic Fibrosis
Instructor, Pediatrics - Pulmonary Medicine
Board Certification, American Board of Pediatrics, Pediatric Pulmonology (2018)
Fellowship:Stanford University Pediatric Pulmonary Fellowship (2018) CA
Residency:Stanford University Pediatric Residency (2015) CA
Board Certification: Pediatrics, American Board of Pediatrics (2014)
Medical Education:Joe and Teresa Lozano Long School of Medicine at UT San Antonio (2011) TX
Current Research and Scholarly Interests
Patients with cystic fibrosis suffer from chronic infection in their airways. Pseudomonas aeruginosa is the most common bacteria found in their lungs and is associated with faster decline in lung function and earlier death. We recently discovered a bacteriophage (virus) that infects Pseudomonas, Pf bacteriophage. This virus turns sputum into a thick goop of molecules called a biofilm that makes infection very difficult to treat. In the laboratory we know that Pf phage makes biofilms more viscous, more adherent, and it helps protect Pseudomonas from both antibiotics and immune cells. I am currently studying the role of Pf phage in patients with cystic fibrosis. We suspect that the presence of Pf phage will be associated with worse clinical outcomes.
- Filamentous bacteriophages are associated with chronic Pseudomonas lung infections and antibiotic resistance in cystic fibrosis SCIENCE TRANSLATIONAL MEDICINE 2019; 11 (488)
- Cystic fibrosis transmembrane conductance regulator modulators: precision medicine in cystic fibrosis CURRENT OPINION IN PEDIATRICS 2018; 30 (3): 372–77
Pf Phage in Chronic Pseudomonas aeruginosa Wound Infections
WILEY. 2018: A5
View details for Web of Science ID 000430308600016
PF BACTERIOPHAGE IN PATIENTS WITH CYSTIC FIBROSIS (CF) IS ASSOCIATED WITH INCREASED SPUTUM ELASTASE AND PSEUDOMONAS AERUGINOSA LOAD
WILEY. 2017: S350
View details for Web of Science ID 000411113700434
Clinical characteristics and outcomes of pediatric patients with CMV DNA detection in bronchoalveolar lavage fluid.
2017; 52 (1): 112-118
Cytomegalovirus (CMV) infection can cause severe pulmonary disease in immunocompromised patients. There are no standard diagnostic criteria for CMV pulmonary disease beyond histopathology findings on lung tissue, which is challenging to obtain in pediatric patients. Bronchoalveolar lavage (BAL) fluid is easier to obtain. Since CMV remains latent after primary infection and can potentially reactivate due to any inflammatory response, CMV detection in BAL specimen may not indicate acute CMV pulmonary disease. Thus, we describe the clinical manifestations and outcomes of pediatric patients with CMV detection in BAL fluid.We reviewed the clinical, radiologic, and laboratory data of patients <19 years old with a BAL specimen positive for CMV during a 5-year period.Thirty-four encounters in 29 patients were found with CMV detected in their BAL specimen. Half (17/34) of the encounters were in immunocompromised patients. CMV, polymerase chain reaction (PCR) was the most common positive test. Forty-seven percent of the patients had other infections detected in BAL specimens. The majority of patients were never treated for CMV and resolved their acute respiratory illness. Only one patient had probable CMV pulmonary disease.CMV is frequently recovered from BAL specimens but does not usually indicate acute CMV pulmonary disease. We would suggest that other diagnoses be considered first, even if CMV is recovered. Pediatr Pulmonol. 2016; 9999:XX-XX. © 2016 Wiley Periodicals, Inc.
View details for DOI 10.1002/ppul.23494
View details for PubMedID 27280337
Molecular and Culture-Based Bronchoalveolar Lavage Fluid Testing for the Diagnosis of Cytomegalovirus Pneumonitis.
Open forum infectious diseases
2016; 3 (1): ofv212-?
Background. Cytomegalovirus (CMV) is a major cause of morbidity and mortality in immunocompromised patients, with CMV pneumonitis among the most severe manifestations of infection. Although bronchoalveolar lavage (BAL) samples are frequently tested for CMV, the clinical utility of such testing remains uncertain. Methods. Retrospective analysis of adult patients undergoing BAL testing via CMV polymerase chain reaction (PCR), shell vial culture, and conventional viral culture between August 2008 and May 2011 was performed. Cytomegalovirus diagnostic methods were compared with a comprehensive definition of CMV pneumonitis that takes into account signs and symptoms, underlying host immunodeficiency, radiographic findings, and laboratory results. Results. Seven hundred five patients underwent 1077 bronchoscopy episodes with 1090 BAL specimens sent for CMV testing. Cytomegalovirus-positive patients were more likely to be hematopoietic cell transplant recipients (26% vs 8%, P < .0001) and less likely to have an underlying condition not typically associated with lung disease (3% vs 20%, P < .0001). Histopathology was performed in only 17.3% of CMV-positive bronchoscopy episodes. When CMV diagnostic methods were evaluated against the comprehensive definition, the sensitivity and specificity of PCR, shell vial culture, and conventional culture were 91.3% and 94.6%, 54.4% and 97.4%, and 28.3% and 96.5%, respectively. Compared with culture, PCR provided significantly higher sensitivity and negative predictive value (P ≤ .001), without significantly lower positive predictive value. Cytomegalovirus quantitation did not improve test performance, resulting in a receiver operating characteristic curve with an area under the curve of 0.53. Conclusions. Cytomegalovirus PCR combined with a comprehensive clinical definition provides a pragmatic approach for the diagnosis of CMV pneumonitis.
View details for DOI 10.1093/ofid/ofv212
View details for PubMedID 26885542
Eosinophilic Pneumonitis As Initial Presentation Of Acute Lymphoblastic Leukemia
AMER THORACIC SOC. 2016
View details for Web of Science ID 000390749607630
- Index of suspicion. Pediatrics in review 2014; 35 (10): 439-446
Case 3 Lactic Acidosis and Cardiovascular Collapse in a Teen With Ulcerative Colitis
PEDIATRICS IN REVIEW
2014; 35 (10): 444–46
View details for Web of Science ID 000421128400006
The impact of the central venous catheter on the diagnosis of infectious endocarditis using Duke criteria in children with Staphylococcus aureus bacteremia
PEDIATRIC INFECTIOUS DISEASE JOURNAL
2008; 27 (7): 636-639
Infective endocarditis (IE) is a known complication of Staphylococcus aureus bacteremia in pediatric patients. We sought to evaluate the impact of prolonged bacteremia associated with a retained central venous catheter (CVC) in the diagnosis of IE using Duke criteria.We conducted a 13-year retrospective review of hospitalized patients with blood cultures positive for S. aureus from 1993 to 2005. Subjects were identified from the microbiology database and medical records. To identify patients with IE we retrospectively applied the Duke criteria by recording the number of positive blood cultures, time to sterilization, presence of congenital heart disease, fever >38.5 degrees C, and echocardiographic findings.During the study period, 344 events of S. aureus bacteremia were identified in 316 pediatric patients. S. aureus bacteremia attributable mortality was 1.7% (n = 6), all among patients with comorbid conditions. By applying the Duke criteria to the 206 (60%) patients who received echocardiographic evaluation, 78 (37.9%) patients were given a diagnosis of IE (7 definite; 71 possible). The incidence of definite IE in patients with CVC is 3.4% and the incidence in patients without CVC is 3.4% (P = 0.6305). The incidence of possible IE in patients with CVC is 42.9%, whereas the incidence in patients without CVC is 23% (P = 0.002).Evaluation for IE is inconsistently done. The presence of a CVC may skew the diagnosis of IE by prolonging the bacteremic state. We believe that a major microbiologic criteria should not be assumed unless cultures remain positive after removal of CVC.
View details for DOI 10.1097/INF.0b013e31816b78c8
View details for Web of Science ID 000257176600010
View details for PubMedID 18520969