Dr. Xingxing Cheng is a practising transplant nephrologist and a clinical investigator with an expertise in decision science. Her clinical practice includes kidney transplant readiness, kidney transplant aftercare, and multi-organ transplantation.

Her overarching research goal is to make better decisions based on the existing technology and state of knowledge. Her current research is in the following areas:
1) the costs, effectiveness, and implementation of work-up before kidney transplantation, including pretransplant cardiovascular screening;
2) ethics of and decision-making in in multi-organ transplantation.

Clinical Focus

  • Nephrology
  • Transplant nephrology
  • Kidney failure in the setting of advanced liver disease

Academic Appointments

Honors & Awards

  • Young Innovator Award, American Society of Transplantation (2016, 2020)
  • Young Investigator Forum 2nd Place in Clinical Sciences, National Kidney Foundation (2017)
  • Career Development Award, American Heart Association (2019-2022)
  • K23 Mentored Patient-Oriented Research Career Development Award, National Institute of Health - National Institute of Diabetes and Digestive and Kidney Diseases (2020-2025)

Professional Education

  • Fellowship: Stanford University Transplant Nephrology Fellowship (2018) CA
  • Fellowship: Stanford University Nephrology Fellowship (2017) CA
  • BS, University of British Columbia, Pharmacology & Therapeutics (2007)
  • BA, University of British Columbia, English (2007)
  • Medical Education: Washington University School Of Medicine Registrar (2011) MO
  • MS, Stanford University, Health Services Research (2017)
  • Residency: Massachusetts General Hospital Internal Medicine Residency (2014) MA
  • Board Certification: American Board of Internal Medicine, Internal Medicine (2014)
  • Board Certification: American Board of Internal Medicine, Nephrology (2016)

Current Research and Scholarly Interests

Dr. Xingxing Cheng's expertise is in applying the tools of decision science to clinical practice and policy analysis. Her current research is in the following areas:
1) the costs, effectiveness, and implementation of work-up before kidney transplantation, including pretransplant cardiovascular screening;
2) ethics of and decision-making in in multi-organ transplantation.

All Publications

  • Emerging Evidence on Coronary Heart Disease Screening in Kidney and Liver Transplantation Candidates: A Scientific Statement From the American Heart Association: Endorsed by the American Society of Transplantation CIRCULATION Cheng, X. S., VanWagner, L. B., Costa, S. P., Axelrod, D. A., Bangalore, S., Norman, S. P., Herzog, C. A., Lentine, K. L., Amer Heart Assoc Council Kidney Ca, Council Cardiovasc Radiology Inter 2022; 146 (21): E299-E324


    Coronary heart disease is an important source of mortality and morbidity among kidney transplantation and liver transplantation candidates and recipients and is driven by traditional and nontraditional risk factors related to end-stage organ disease. In this scientific statement, we review evidence from the past decade related to coronary heart disease screening and management for kidney and liver transplantation candidates. Coronary heart disease screening in asymptomatic kidney and liver transplantation candidates has not been demonstrated to improve outcomes but is common in practice. Risk stratification algorithms based on the presence or absence of clinical risk factors and physical performance have been proposed, but a high proportion of candidates still meet criteria for screening tests. We suggest new approaches to pretransplantation evaluation grounded on the presence or absence of known coronary heart disease and cardiac symptoms and emphasize multidisciplinary engagement, including involvement of a dedicated cardiologist. Noninvasive functional screening methods such as stress echocardiography and myocardial perfusion scintigraphy have limited accuracy, and newer noninvasive modalities, especially cardiac computed tomography-based tests, are promising alternatives. Emerging evidence such as results of the 2020 International Study of Comparative Health Effectiveness With Medical and Invasive Approaches-Chronic Kidney Disease trial emphasizes the vital importance of guideline-directed medical therapy in managing diagnosed coronary heart disease and further questions the value of revascularization among asymptomatic kidney transplantation candidates. Optimizing strategies to disseminate and implement best practices for medical management in the broader end-stage organ disease population should be prioritized to improve cardiovascular outcomes in these populations.

    View details for DOI 10.1161/CIR.0000000000001104

    View details for Web of Science ID 000886687700001

    View details for PubMedID 36252095

  • Trends in Cost Attributable to Kidney Transplantation Evaluation and Waiting List Management in the United States, 2012-2017. JAMA network open Cheng, X. S., Han, J., Braggs-Gresham, J. L., Held, P. J., Busque, S., Roberts, J. P., Tan, J. C., Scandling, J. D., Chertow, G. M., Dor, A. 2022; 5 (3): e221847


    Importance: While recent policy reforms aim to improve access to kidney transplantation for patients with end-stage kidney disease, the cost implications of kidney waiting list expansion are not well understood. The Organ Acquisition Cost Center (OACC) is the mechanism by which Medicare reimburses kidney transplantation programs, at cost, for costs attributable to kidney transplantation evaluation and waiting list management, but these costs have not been well described to date.Objectives: To describe temporal trends in mean OACC costs per kidney transplantation and to identify factors most associated with cost.Design, Setting, and Participants: This economic evaluation included all kidney transplantation waiting list candidates and recipients in the United States from 2012 to 2017. A population-based study of cost center reports was conducted using data from all Center of Medicare & Medicaid-certified transplantation hospitals. Data analysis was conducted from June to August 2021.Exposures: Year, local price index, transplantation and waiting list volume of transplantation program, and comorbidity burden.Main Outcomes and Measures: Mean OACC costs per kidney transplantation.Results: In 1335 hospital-years from 2012 through 2017, Medicare's share of OACC costs increased from $0.95 billion in 2012 to $1.32 billion in 2017 (3.7% of total Medicare End-Stage Renal Disease program expenditure). Median (IQR) OACC costs per transplantation increased from $81 000 ($66 000 to $103 000) in 2012 to $100 000 ($82 000 to $125 000) in 2017. Kidney organ procurement costs contributed to 36% of mean OACC costs per transplantation throughout the study period. During the study period, transplantation hospitals experienced increases in kidney waiting list volume, kidney waiting list active volume, kidney transplantation volume, and comorbidity burden. For a median-sized transplantation program, mean OACC costs per transplantation decreased with more transplants (-$3500 [95% CI, -$4300 to -$2700] per 10 transplants; P<.001) and increased with year ($4400 [95% CI, $3500 to $5300] per year; P<.001), local price index ($1900 [95% CI, $200 to $3700] per 10-point increase; P=.03), patients listed active on the waiting list ($3100 [95% CI, $1700 to $4600] per 100 patients; P<.001), and patients on the waiting list with high comorbidities ($1500 [9% CI, $600 to $2500] per 1% increase in proportion of waitlisted patients with the highest comorbidity score; P=.002).Conclusions and Relevance: In this study, OACC costs increased at 4% per year from 2012 to 2017 and were not solely attributable to the cost of organ procurement. Expanding the waiting list will likely contribute to further increases in the mean OACC costs per transplantation and substantially increase Medicare liability.

    View details for DOI 10.1001/jamanetworkopen.2022.1847

    View details for PubMedID 35267033

  • The Organ Procurement Costs of Expanding Deceased Donor Organ Acceptance Criteria: Evidence from a Cost Function Model. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons Cheng, X. S., Held, P. J., Dor, A., Bragg-Gresham, J. L., Tan, J. C., Scandling, J. D., Chertow, G. M., Roberts, J. P. 2021


    A potential solution to the deceased donor organ shortage is to expand donor acceptability criteria. The procurement cost implications of using non-standard donors is unknown. Using five years of United States (US) organ procurement organization (OPO) data, we built a cost function model to make cost projections: the total cost was the dependent variable; production outputs, including the number of donors and organs procured, were the independent variables. In the model, procuring one kidney from a donor (single-organ donor) or procuring both kidneys from double/en bloc transplantation resulted in a marginal cost of $55k (95% confidence interval [CI] $28k-$99k) per kidney, and procuring only the liver from a donor results in a marginal cost of $41k (95% CI $12k-69k) per liver. Procuring two kidneys for two candidates from a donor lowered the marginal cost to $36k (95% CI $22k-$66k) per kidney, and procuring two kidneys and a liver lowers the marginal cost to $24k per organ (95% CI $17k-$45k). Economies of scale were observed, where high OPO volume correlated with lower costs. Despite higher cost per organ than for standard donors, kidney transplantation from non-standard donors remained cost effective based on contemporary US data.

    View details for DOI 10.1111/ajt.16617

    View details for PubMedID 33884757

  • Defining a willingness-to-transplant threshold in an era of organ scarcity: Simultaneous liver-kidney transplant as a case example. Transplantation Cheng, X. S., Goldhaber-Fiebert, J. n., Tan, J. C., Chertow, G. M., Kim, W. R., Wall, A. E. 2019


    Organ scarcity continues in solid organ transplantation, such that the availability of organs limits the number of people able to benefit from transplantation. Medical advancements in managing end-stage organ disease have led to an increasing demand for multi-organ transplant, wherein a patient with multi-organ disease receives more than one organ from the same donor. Current allocation schemes give priority to multi-organ recipients over single-organ transplant recipients, which raises ethical questions regarding equity and utility.We use simultaneous liver-kidney (SLK) transplant, a type of multi-organ transplant, as a case study to examine the tension between equity and utility in multi-organ allocation. We adapt the health economics willingness-to-pay threshold to a solid organ transplant setting by coining a new metric: the willingness-to-transplant (WTT) threshold.We demonstrate how the WTT threshold can be used to evaluate different SLK allocation strategies by synthesizing utility and equity perspectives.We submit that this new framework enables us to distill the question of SLK allocation down to: what is the minimum amount of benefit we require from a deceased donor kidney to allocate it for a particular indication? Addressing the above question will prove helpful to devising a rational system of SLK allocation and is applicable to other transplant settings.

    View details for DOI 10.1097/TP.0000000000002788

    View details for PubMedID 31107820

  • A New Approach to Kidney Waitlist Management in the Kidney Allocation System Era: Pilot Implementation and Evaluation. Clinical transplantation Cheng, X. S., Busque, S., Lee, J., Discipulo, K., Hartley, C., Tulu, Z., Scandling, J. D., Tan, J. C. 2018: e13406


    Kidney transplant waitlist management is becoming increasingly complex. We introduced a novel waitlist management strategy at our center, the Transplant Readiness Assessment Clinic (TRAC), whereby patients whose Kidney Allocation Scores surpass a threshold are actively managed. From January 1, 2016 through June 30, 2017, we evaluated 195 patients through TRAC. Compared to pre-TRAC systems at our institution, TRAC resulted in a higher proportion of activation at 18-months (38% versus 22-26%, p<0.0001), despite being enriched in patients with long dialysis duration. TRAC also resulted in a higher proportion of waitlist removal (15% versus 8-9%, p<0.05) although combined waitlist removal and death on waitlist did not differ (18% versus 16-17%). Median time-to-activation was 356 days from TRAC evaluation. Of the transplant barriers, need for cardiovascular studies was the most common (31%), followed by other medical issues (23%), poor functional status (13%), and psychosocial issues (10%). By concentrating center resources on patients most likely to be transplanted after activation and performing active patient management close to the time of transplant, TRAC has the potential to significantly enhance kidney transplant success in regions with long wait-times. This article is protected by copyright. All rights reserved.

    View details for PubMedID 30218580

  • Referral and Beyond: Restructuring the Kidney Transplant Process to Support Greater Access in the United States. American journal of kidney diseases : the official journal of the National Kidney Foundation Butler, C. R., Reese, P. P., Cheng, X. S. 2024


    Advocates for improved equity in kidney transplant in the US have recently focused efforts on initiatives to increase referral for transplant evaluation. However, because donor kidneys remain scarce, increased referrals are likely to result in an increasing number of patients proceeding through the evaluation process without ultimately receiving a kidney. Unfortunately, the process of referral and evaluation can be highly resource-intensive for patients, families, transplant programs, and payers. Patients and families may incur out-of-pocket expenses and be required to complete testing and treatments that they might not have chosen in the course of routine clinical care. Kidney transplant programs may struggle with insufficient capacity, inefficient workflow, and challenging programmatic finances and payers will need to absorb the increased expenses of upfront pretransplant costs. Increased referral in isolation may risk simply transmitting system stress and resulting disparities to downstream processes in this complex system. We argue that success in efforts to improve access through increased referrals hinges on adaptations to the pretransplant process more broadly. We call for an urgent reevaluation and redesign at multiple levels of the pretransplant system in order to achieve the aim of equitable access to kidney transplantation for all patients with kidney failure.

    View details for DOI 10.1053/j.ajkd.2024.03.017

    View details for PubMedID 38670253

  • Maximizing Utility of Deceased Donor Kidney Offers. Clinical journal of the American Society of Nephrology : CJASN Caldwell, J. S., Cheng, X. S. 2023; 18 (12): 1521-1523

    View details for DOI 10.2215/CJN.0000000000000349

    View details for PubMedID 38064304

  • Incidence of Kidney Failure after Primary Organ Transplant. Kidney360 Jan, A., Schappe, T., Caddell, K. B., Cheng, X. S., Sanoff, S., Lu, Y., Shaw, B. I., Samoylova, M. L., Peskoe, S., Pendergast, J., McElroy, L. 2023


    Careful selection of multiorgan transplant candidates is required to avoid unintended consequences to patients waiting for kidney transplant alone. The need for a safety net among heart and lung transplant recipients is unknown. The objective of this study was to quantify the incidence of kidney failure after liver, heart, or lung transplantation and identify pre-transplant predictors of post-transplant kidney failure.A retrospective cross-sectional study of adults who received liver, heart, or lung transplant between January 1, 2008 and December 31, 2018 was conducted using data from the Scientific Registry of Transplant Recipient and the United States Renal Data System. Post-transplant renal failure was defined as (a) new start of dialysis; (b) estimated glomerular filtration rate of < 25 mL/min; (c) a new waitlisting for a kidney transplant; or (d) receipt of a kidney transplant.The final descriptive cohort 53,620 liver transplant recipients, 22,042 heart transplant recipients, and 10,688 lung transplant recipients. In the first-year post-transplant, the probability of ESKD was comparable among heart transplant recipients (0.036, 95% CI [0.033, 0.038]) and liver transplant recipients (0.033, 95% CI [0.031, 0.035]) but was markedly lower in lung transplant recipients (0.024, 95% CI [0.021, 0.027]). In the second-year post-transplant, the probability of ESKD was comparable among liver (0.016, 95% CI [0.015, 0.017]), lung (0.018, 95% CI [0.015, 0.021]), and heart transplant recipients (0.014, 95% CI [0.013, 0.016]).Candidates for thoracic transplant would likely benefit from a safety net policy similar to the one enacted in 2017 for liver transplant, so as to maintain judicious patient selection for simultaneous multi-organ transplant. National data sources do not currently collect sufficiently reliable follow up data to identify pre-transplant predictors of end stage kidney disease, pointing to a need for transplant centers to consistently report kidney impairment data to national databases.

    View details for DOI 10.34067/KID.0000000000000315

    View details for PubMedID 37968797

  • Maximizing Utility of Deceased Donor Kidney Offers. Clinical journal of the American Society of Nephrology : CJASN Caldwell, J. S., Cheng, X. S. 2023

    View details for DOI 10.2215/CJN.0000000000000349

    View details for PubMedID 37930931

  • Dual-Organ Transplantation: Indications, Evaluation, and Outcomes for Heart-Kidney and Heart-Liver Transplantation: A Scientific Statement From the American Heart Association CIRCULATION Kittleson, M., Sharma, K. C., Brennan, D. S., Cheng, X. L., Chow, S., Colvin, M. D., DeVore, A. M., Dunlay, S., Fraser, M., Garonzik-Wang, J., Khazanie, P. M., Korenblat, K. T., Pham, D. 2023; 148 (7): 622-636


    Although heart transplantation is the preferred therapy for appropriate patients with advanced heart failure, the presence of concomitant renal or hepatic dysfunction can pose a barrier to isolated heart transplantation. Because donor organ supply limits the availability of organ transplantation, appropriate allocation of this scarce resource is essential; thus, clear guidance for simultaneous heart-kidney transplantation and simultaneous heart-liver transplantation is urgently required. The purposes of this scientific statement are (1) to describe the impact of pretransplantation renal and hepatic dysfunction on posttransplantation outcomes; (2) to discuss the assessment of pretransplantation renal and hepatic dysfunction; (3) to provide an approach to patient selection for simultaneous heart-kidney transplantation and simultaneous heart-liver transplantation and posttransplantation management; and (4) to explore the ethics of multiorgan transplantation.

    View details for DOI 10.1161/CIR.0000000000001155

    View details for Web of Science ID 001046000500013

    View details for PubMedID 37439224

  • One size does not fit all: Differential benefits of simultaneous liver-kidney transplantation by eligibility criteria. Liver transplantation : official publication of the American Association for the Study of Liver Diseases and the International Liver Transplantation Society Cheng, X. S., McElroy, L. M., Sanoff, S. L., Kwong, A. J. 2023


    Standard eligibility criteria for simultaneous liver-kidney transplantation (SLK) are in place in the United States (US). We hypothesize that the benefit associated with SLK over liver transplant alone differs by patient, depending on the specific SLK criteria met. We analyzed a retrospective US cohort of 5,446 adult liver transplant or SLK recipients between January 1, 2015 and December 31, 2018 who potentially qualified for SLK. Exposure was receipt of SLK. We tested effect modification by the specific SLK eligibility criteria met (endstage kidney disease [ESKD], acute kidney injury [AKI], chronic kidney disease [CKD], or unknown). Primary outcome was death within 1 year of liver transplant. We used a modified Cox regression analysis containing an interaction term of SLK  time from transplant. 210 (9%) SLK recipients and 351 (11%) liver-alone recipients died in 1 year. In the overall population, SLK was associated with a mortality benefit over liver transplant on the day of transplant, without adjustment (hazard ratio [HR] 0.59 [95% confidence interval [CI] 0.46-0.76]) and with adjustment (aHR 0.50 [95% CI 0.35-0.71]). However, when SLK eligibility criteria was included, only in patients with ESKD was SLK associated with a sustained survival benefit at day 0 (HR 0.17 [0.08-0.35]) up to 288 (95% CI 120-649) days posttransplant. Benefit within the first year posttransplant associated with SLK over liver-alone transplantation was only pronounced in patients with ESKD, but not present in patients meeting other criteria for SLK. A "strict SLK liberal Safety Net" strategy may warrant consideration at the national policy level.

    View details for DOI 10.1097/LVT.0000000000000191

    View details for PubMedID 37329171

  • Preoperative Evaluations Before Transplantation-Essential Tools, Not Obstacles-Reply. JAMA internal medicine Cheng, X. S. 2023

    View details for DOI 10.1001/jamainternmed.2023.1242

    View details for PubMedID 37184870

  • Kidney Stone Events after Kidney Transplant in the United States. Clinical journal of the American Society of Nephrology : CJASN Ganesan, C., Holmes, M., Liu, S., Montez-Rath, M., Conti, S., Chang, T. C., Lenihan, C. R., Cheng, X. S., Chertow, G. M., Leppert, J. T., Pao, A. C. 2023


    BACKGROUND: Kidney stone disease is common and can lead to complications such as acute kidney injury, urinary tract obstruction, and urosepsis. In kidney transplant recipients, complications from kidney stone events can also lead to rejection and allograft failure. There is limited information on the incidence of kidney stone events in transplant recipients.METHODS: We identified 83,535 patients from the United States Renal Data System who received their first kidney transplant between January 1st, 2007 and December 31st, 2018. We examined the incidence of kidney stone events and identified risk factors associated with a kidney stone event in the first 3 years after transplantation.RESULTS: We found 1,436 (1.7%) patients who were diagnosed with a kidney stone in the 3 years following kidney transplant. The unadjusted incidence rate for a kidney stone event was 7.8 per 1000 person-years. The median time from transplant to a kidney stone diagnosis was 0.61 (25%,75% range 0.19-1.46) years. Patients with a prior history of kidney stones were at greatest risk for a kidney stone event after transplant (HR 4.65; 95% CI, 3.82-5.65). Other notable risk factors included a diagnosis of gout (HR 1.53; 95% CI, 1.31-1.80), hypertension (HR 1.29; 95% CI, 1.00-1.66), and a dialysis of vintage of > 9 years (HR 1.48; 95% CI, 1.18-1.86; ref vintage < 2.5 years).CONCLUSIONS: Approximately 2% of kidney transplant recipients were diagnosed with a kidney stone in the 3 years following kidney transplant. Risk factors for a kidney stone event include a prior history of kidney stones and longer dialysis vintage.

    View details for DOI 10.2215/CJN.0000000000000176

    View details for PubMedID 37071657

  • Association of Pretransplant Coronary Heart Disease Testing With Early Kidney Transplant Outcomes. JAMA internal medicine Cheng, X. S., Liu, S., Han, J., Stedman, M. R., Baiocchi, M., Tan, J. C., Chertow, G. M., Fearon, W. F. 2023


    Importance: Testing for coronary heart disease (CHD) in asymptomatic kidney transplant candidates before transplant is widespread and endorsed by various professional societies, but its association with perioperative outcomes is unclear.Objective: To estimate the association of pretransplant CHD testing with rates of death and myocardial infarction (MI).Design, Setting, and Participants: This retrospective cohort study included all adult, first-time kidney transplant recipients from January 2000 through December 2014 in the US Renal Data System with at least 1 year of Medicare enrollment before and after transplant. An instrumental variable (IV) analysis was used, with the program-level CHD testing rate in the year of the transplant as the IV. Analyses were stratified by study period, as the rate of CHD testing varied over time. A combination of US Renal Data System variables and Medicare claims was used to ascertain exposure, IV, covariates, and outcomes.Exposures: Receipt of nonurgent invasive or noninvasive CHD testing during the 12 months preceding kidney transplant.Main Outcomes and Measures: The primary outcome was a composite of death or acute MI within 30 days of after kidney transplant.Results: The cohort comprised 79 334 adult, first-time kidney transplant recipients (30 147 women [38%]; 25 387 [21%] Black and 48 394 [61%] White individuals; mean [SD] age of 56 [14] years during 2012 to 2014). The primary outcome occurred in 4604 patients (244 [5.3%]; 120 [2.6%] death, 134 [2.9%] acute MI). During the most recent study period (2012-2014), the CHD testing rate was 56% in patients in the most test-intensive transplant programs (fifth IV quintile) and 24% in patients at the least test-intensive transplant program (first IV quintile, P<.001); this pattern was similar across other study periods. In the main IV analysis, compared with no testing, CHD testing was not associated with a change in the rate of primary outcome (rate difference, 1.9%; 95% CI, 0%-3.5%). The results were similar across study periods, except for 2000 to 2003, during which CHD testing was associated with a higher event rate (rate difference, 6.8%; 95% CI, 1.8%-12.0%).Conclusions and Relevance: The results of this cohort study suggest that pretransplant CHD testing was not associated with a reduction in early posttransplant death or acute MI. The study findings potentially challenge the ubiquity of CHD testing before kidney transplant and should be confirmed in interventional studies.

    View details for DOI 10.1001/jamainternmed.2022.6069

    View details for PubMedID 36595271

  • Is Prioritization of Kidney Allografts to Combined Liver-Kidney Recipients Appropriate? CON KIDNEY360 Cheng, X. S. 2022; 3 (6): 996-998
  • Trends in Coronary Artery Disease Screening before Kidney Transplantation. Kidney360 Cheng, X. S., Liu, S., Han, J., Stedman, M. R., Chertow, G. M., Tan, J. C., Fearon, W. F. 2022; 3 (3): 516-523


    Background: Coronary artery disease (CAD) screening in asymptomatic kidney transplant candidates is widespread but not well supported by contemporary cardiology literature. In this study we describe temporal trends in CAD screening before kidney transplant in the United States.Methods: Using the United States Renal Data System, we examined Medicare-insured adults who received a first kidney transplant from 2000 through 2015. We stratified analysis on the basis of whether the patient's comorbidity burden met guideline definitions of high risk for CAD. We examined temporal trends in nonurgent CAD tests within the year before transplant and the composite of death and nonfatal myocardial infarction in the 30 days after transplant.Results: Of 94,832 kidney transplant recipients, 37,139 (39%) underwent at least one nonurgent CAD test in the 1 year before transplant. From 2000 to 2015, the transplant program waitlist volume had increased as transplant volume stayed constant, whereas patients in the later eras had a slightly higher comorbidity burden (older, longer dialysis vintage, and a higher prevalence of diabetes mellitus and CAD). The likelihood of CAD test in the year before transplant increased from 2000 through 2003 and remained relatively stable thereafter. When stratified by CAD risk status, test rates decreased modestly in patients who were high risk but remained constant in patients who were low risk after 2008. Death or nonfatal myocardial infarction within 30 days after transplant decreased from 3% in 2000 to 2% in 2015. Nuclear perfusion scan was the most frequent modality of testing throughout the examined time periods.Conclusions: CAD testing rates before kidney transplantation have remained constant from 2000 through 2015, despite widespread changes in cardiology guidelines and practice.

    View details for DOI 10.34067/KID.0005282021

    View details for PubMedID 35582172

  • Center variations in patient selection for simultaneous heart-kidney transplantation. Clinical transplantation Shaw, B. I., Samoylova, M. L., Barbas, A. S., Cheng, X. S., Lu, Y., McElroy, L. M., Sanoff, S. 2022: e14619


    There are no established regulations governing patient selection for simultaneous heart-kidney transplantation (SHK), creating the potential for significant center-level variations in clinical practice. Using the United Network for Organ Sharing (UNOS) Standard Transplant Analysis and Research (STAR) file we examined practice trends and variations in patient selection for SHK at the center level between Jan 1, 2004 and March 31, 2019. Overall, SHK is becoming more common with most centers performing heart transplants also performing SHK. Among patients who underwent heart transplant who were receiving dialysis, the rate of SHK varied from 22% to 86% at the center level. Among patients not on dialysis, the median eGFR of patients receiving SHK varied between 19-59mL/min/1.73m2 . When adjusting for other factors, the odds of SHK varied 57-fold between the highest and lowest SHK performing centers. Variation in SHK at the center level suggests the need for national guidelines around the selection of patients for SHK. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1111/ctr.14619

    View details for PubMedID 35175664

  • Optimal patient selection for simultaneous heart-kidney transplant: a modified cost-effectiveness analysis. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons Wayda, B., Cheng, X. S., Goldhaber-Fiebert, J. D., Khush, K. K. 2021


    Increasing rates of simultaneous heart-kidney (SHK) transplant in the United States exacerbate the overall shortage of deceased donor kidneys (DDK). Current allocation policy does not impose constraints on SHK eligibility, and how best to do so remains unknown. We apply a decision analytic model to evaluate options for heart transplant (HT) candidates with comorbid kidney dysfunction. We compare SHK with a "Safety Net" strategy, in which DDK transplant is performed six months after HT, only if native kidneys do not recover. We identify patient subsets for whom SHK using a DDK is efficient, considering the quality-adjusted life year (QALY) gains from DDKs instead allocated for kidney transplant-only. For an average-aged candidate with 50% probability of kidney recovery after HT-only, SHK produces 0.64 more QALYs than Safety Net at a cost of 0.58 more kidneys used. SHK is inefficient in this scenario, producing fewer QALYs per DDK used (1.1) than a DDK allocated for KT-only (2.2). SHK is preferred to Safety Net only for candidates with a lower probability of native kidney recovery (24 - 38%, varying by recipient age). This finding favors implementation of a Safety Net provision and should inform the establishment of objective criteria for SHK transplant eligibility.

    View details for DOI 10.1111/ajt.16888

    View details for PubMedID 34741786

  • Racial Disparities in Pediatric Kidney Transplantation under the New Kidney Allocation System in the United States. Clinical journal of the American Society of Nephrology : CJASN Krissberg, J., Kaufmann, M., Gupta, A., Bendavid, E., Stedman, M., Cheng, X., Tan, J., Grimm, P., Chaudhuri, A. 2021


    Background and Objectives: In December 2014, the Kidney Allocation System (KAS) was implemented to improve equity in access to transplantation, but preliminary studies in children show mixed results. Thus, we aimed to assess how the 2014 KAS policy change affected racial/ethnic disparities in pediatric kidney transplantation access and related outcomes. Design, setting, participants, and measurements: A retrospective cohort study of children <18 years of age active on the kidney transplant list from 2008 to 2019 using the Scientific Registry of Transplant Recipients. Log-logistic accelerated failure time models were used to determine time from first activation on the transplant list and time on dialysis to deceased-donor transplant, each with KAS era or race/ethnicity as the exposure of interest. We used logistic regression to assess odds of delayed graft function. Log-rank tests assessed time to graft loss within racial/ethnic groups across KAS eras. Results: All children experienced longer wait times from activation to transplantation post-KAS. In univariable analysis, Black or Hispanic children or other children of color experienced longer times from activation to transplant compared to White children in the both eras; this finding was largely attenuated after multivariable analysis (time ratio 1.16, (95% CI 1.01-1.32); 1.13 (1.00-1.28); 1.17 (0.96-1.41) post-KAS, respectively). Multivariable analysis also showed that racial/ethnic disparities in time from dialysis initiation to transplantation in the pre-KAS era was mitigated in the post-KAS era. There were no disparities in odds of delayed graft function. Black or Hispanic children experienced longer times with a functioning graft in the post-KAS era. Conclusions: No racial/ethnic disparities from activation to deceased donor transplantation were seen before or after implementation of KAS in multivariable analysis, while time on dialysis to transplantation and odds of short-term graft loss improved in equity after KAS, without compromising disparities in delayed graft function.

    View details for DOI 10.2215/CJN.06740521

    View details for PubMedID 34670797

  • Recurrence of IgA Nephropathy after Kidney Transplantation in Adults. Clinical journal of the American Society of Nephrology : CJASN Uffing, A., Perez-Saez, M. J., Jouve, T., Bugnazet, M., Malvezzi, P., Muhsin, S. A., Lafargue, M., Reindl-Schwaighofer, R., Morlock, A., Oberbauer, R., Buxeda, A., Burballa, C., Pascual, J., von Moos, S., Seeger, H., La Manna, G., Comai, G., Bini, C., Russo, L. S., Farouk, S., Nissaisorakarn, P., Patel, H., Agrawal, N., Mastroianni-Kirsztajn, G., Mansur, J., Tedesco-Silva, H., Ventura, C. G., Agena, F., David-Neto, E., Akalin, E., Alani, O., Mazzali, M., Manfro, R. C., Bauer, A. C., Wang, A. X., Cheng, X. S., Schold, J. D., Berger, S. P., Cravedi, P., Riella, L. V. 2021; 16 (8): 1247-1255


    BACKGROUND AND OBJECTIVES: In patients with kidney failure due to IgA nephropathy, IgA deposits can recur in a subsequent kidney transplant. The incidence, effect, and risk factors of IgA nephropathy recurrence is unclear, because most studies have been single center and sample sizes are relatively small.DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We performed a multicenter, international, retrospective study to determine the incidence, risk factors, and treatment response of recurrent IgA nephropathy after kidney transplantation. Data were collected from all consecutive patients with biopsy-proven IgA nephropathy transplanted between 2005 and 2015, across 16 "The Post-Transplant Glomerular Disease" study centers in Europe, North America, and South America.RESULTS: Out of 504 transplant recipients with IgA nephropathy, recurrent IgA deposits were identified by kidney biopsy in 82 patients; cumulative incidence of recurrence was 23% at 15 years (95% confidence interval, 14 to 34). Multivariable Cox regression revealed a higher risk for recurrence of IgA deposits in patients with a pre-emptive kidney transplant (hazard ratio, 3.45; 95% confidence interval, 1.31 to 9.17) and in patients with preformed donor-specific antibodies (hazard ratio, 2.59; 95% confidence interval, 1.09 to 6.19). After kidney transplantation, development of de novo donor-specific antibodies was associated with subsequent higher risk of recurrence of IgA nephropathy (hazard ratio, 6.65; 95% confidence interval, 3.33 to 13.27). Immunosuppressive regimen was not associated with recurrent IgA nephropathy in multivariable analysis, including steroid use. Graft loss was higher in patients with recurrence of IgA nephropathy compared with patients without (hazard ratio, 3.69; 95% confidence interval, 2.04 to 6.66), resulting in 32% (95% confidence interval, 50 to 82) graft loss at 8 years after diagnosis of recurrence.CONCLUSIONS: In our international cohort, cumulative risk of IgA nephropathy recurrence increased after transplant and was associated with a 3.7-fold greater risk of graft loss.

    View details for DOI 10.2215/CJN.00910121

    View details for PubMedID 34362788

  • Performance versus Risk Factor-Based Approaches to Coronary Artery Disease Screening in Waitlisted Kidney Transplant Candidates. Cardiorenal medicine Cheng, X. S., Watford, D. J., Arashi, H., Stedman, M. R., Chertow, G. M., Tan, J. C., Fearon, W. F. 2021: 1-11


    INTRODUCTION: Current screening algorithms for coronary artery disease (CAD) before kidney transplantation result in many tests but few interventions.OBJECTIVE: The aim of this study was to study the utility of 6-minute walk test (6MWT), an office-based test of cardiorespiratory fitness, for risk stratification in this setting.METHODS: We enrolled 360 patients who are near the top of the kidney transplant waitlist at our institution. All patients underwent CAD evaluation irrespective of 6MWT results. We examined the association between 6MWT and time to CAD-related events (defined as cardiac death, revascularization, nonfatal myocardial infarction, and removal from the waitlist for CAD), treating noncardiac death and waitlist removal for non-CAD reasons as competing events.RESULTS: The 6MWT-based approach designated approximately 45% of patients as "low risk," whereas a risk factor- or symptom-based approach designated 14 and 81% of patients as "low risk," respectively. The 6MWT-based approach was not significantly associated with CAD-related events within 1 year (subproportional hazard ratio [sHR] 1.00 [0.90-1.11] per 50 m) but was significantly associated with competing events (sHR 0.70 [0.66-0.75] per 50 m). In a companion analysis, removing waitlist status from consideration, 6MWT result was associated with the development of CAD-related events (sHR 0.92 [0.84-1.00] per 50 m).CONCLUSIONS: The 6MWT designates fewer patients as high risk and in need of further testing (compared to risk factor-based approaches), but its utility as a pure CAD risk stratification tool is modulated by the background waitlist removal rate. CAD screening before kidney transplant should be tailored according to a patient's actual chance of receiving a transplant.

    View details for DOI 10.1159/000516158

    View details for PubMedID 34034263

  • Feasibility and Effectiveness of Norepinephrine Outside the Intensive Care Setting for Treatment of Hepatorenal Syndrome. Liver transplantation : official publication of the American Association for the Study of Liver Diseases and the International Liver Transplantation Society Kwong, A., Kim, W. R., Kwo, P. Y., Wang, U., Cheng, X. 2021


    BACKGROUND & AIMS: Vasoconstrictors are the treatment of choice for hepatorenal syndrome (HRS), a potentially lethal complication of end-stage liver disease. We evaluate the real-life effectiveness of a sequential vasoconstrictor regimen of midodrine-octreotide followed by norepinephrine in a non-ICU setting in the United States, where terlipressin is not available.APPROACH & RESULTS: Adult patients diagnosed with HRS were treated with oral midodrine and subcutaneous octreotide in conjunction with albumin. The diagnosis of HRS and definitions of acute kidney injury were based on 2015 guidelines from the International Club of Ascites. A partial response was defined as regression of acute kidney injury (AKI) stage with reduction in serum creatinine to ≥0.3 mg/dL above baseline, whereas a full response was regression of AKI stage with return to a value within 0.3 mg/dL of baseline. In patients without partial or full response, norepinephrine was administered at a starting dose of 5 mcg/min, with a goal to achieve a mean arterial pressure (MAP) of 10 mmHg above baseline. We assessed predictors of response and treatment outcomes. 61 patients received midodrine and octreotide for the treatment of HRS, with a 28% response rate. The median MELD-Na was 30 (IQR 24-35), with median MAP of 73 mmHg (IQR 67-79) at the start of treatment. Responders were more likely to have alcohol-related liver disease and lower ACLF grade. Of the non-responders, 20 then received norepinephrine, of whom 45% achieved full or partial response. Achieving MAP increase of ≥10 mmHg was associated with a greater probability of response. Patients who responded to norepinephrine experienced improved transplant-free survival at 90 days (88% v. 27%, p=0.02). Five of 20 patients experienced norepinephrine treatment-related adverse events, namely arrhythmias.CONCLUSION: Norepinephrine can be effectively used in a non-ICU setting as rescue therapy in patients who have not responded to midodrine and octreotide. Based on these data, we propose a practical stepwise algorithm for vasoconstrictor therapy to manage HRS in situations where terlipressin is not an option.

    View details for DOI 10.1002/lt.26065

    View details for PubMedID 33837624

  • Incorporating kidney-related multi-organ transplants into the kidney allocation sequence. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons Cheng, X. S., Reese, P. P. 2021


    We read with great interest "The impact of multi-organ transplant allocation priority on wait-listed kidney transplant candidates."1 Unfortunately, the need for deceased donor kidneys far outstrips the supply, and the transplant community is tasked with rationing those organs based on existing legal and ethical frameworks.

    View details for DOI 10.1111/ajt.16542

    View details for PubMedID 33594713

  • Consensus Conference on Heart-Kidney Transplantation. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons Kobashigawa, J., Dadhania, D. M., Farr, M., Tang, W. H., Bhimaraj, A., Czer, L., Hall, S., Haririan, A., Formica, R. N., Patel, J., Skorka, R., Fedson, S., Srinivas, T., Testani, J., Yabu, J. M., Cheng, X. S., Consensus Conference Participants 2021


    Simultaneous heart-kidney transplant (sHK) has enabled the successful transplantation of patients with end-stage heart disease and concomitant kidney disease, with non-inferior outcomes to heart transplant (HT) alone. The decision for sHK is challenged by difficulties in differentiating those patients with a significant component of reversible kidney injury due to cardiorenal syndrome who may recover kidney function after HT, from those with intrinsic advanced kidney disease who would benefit most from sHK. A consensus conference on sHK took place on June 1, 2019 in Boston, Massachusetts. The conference represented a collaborative effort by experts in cardiothoracic and kidney transplantation from centers across the United States to explore the development of guidelines for the interdisciplinary criteria for kidney transplantation in the sHK candidate, to evaluate the current allocation of kidneys to follow the heart for sHK, and to recommend standardized care for the management of sHK recipients. The conference served as a forum to unify criteria between the different specialties and to forge a pathway for patients who may need dual organ transplantation. Due to the continuing shortage of available donor organs, ethical problems related to multi-organ transplantation were also debated. The findings and consensus statements are presented.

    View details for DOI 10.1111/ajt.16512

    View details for PubMedID 33527725

  • And Then There Were Three: Effects of Pretransplant Dialysis on Multiorgan Transplantation. Transplantation direct Cheng, X. S., Han, J., Stedman, M. R., Chertow, G. M., Tan, J. C. 2021; 7 (2): e657


    Background: Simultaneous liver-kidney (SLK) and simultaneous heart-kidney (SHK) transplantation currently utilize 6% of deceased donor kidneys in the United States. To what extent residual kidney function accounts for apparent kidney allograft survival is unknown.Methods: We examined all adult SLK and SHK transplants in the United States during 1995-2014. We considered the duration of dialysis preceding SLK or SHK (≥90 d, 1-89 d, or none) as a proxy of residual kidney function. We used multinomial logistic regression to estimate the difference in the adjusted likelihood of 6- and 12-month apparent kidney allograft failure between the no dialysis versus ≥90 days dialysis groups.Results: Of 4875 SLK and 848 SHK recipients, 1775 (36%) SLK and 449 (53%) SHK recipients received no dialysis before transplant. The likelihood of apparent kidney allograft failure was 1%-3% lower at 12 months in SLK and SHK recipients who did not require pretransplant dialysis relative to recipients who required ≥90 days of pretransplant dialysis. Among 3978 SLK recipients who survived to 1 year, no pretransplant dialysis was associated with a lower risk of apparent kidney allograft failure over a median follow-up of 5.7 years (adjusted hazard ratio 0.73 [0.55-0.96]).Conclusions: Patients with residual kidney function at the time of multiorgan transplantation are less likely to have apparent failure of the kidney allograft. Whether residual kidney function facilitates function of the allograft or whether some SLK and SHK recipients have 3 functional kidneys is unknown. Sustained kidney function after SLK and SHK transplants does not necessarily indicate successful MOT.

    View details for DOI 10.1097/TXD.0000000000001112

    View details for PubMedID 33490382

  • Ethical decision-making in simultaneous heart-liver transplantation. Current opinion in organ transplantation Cheng, X. S., Wall, A., Teuteberg, J. 2020


    PURPOSE OF REVIEW: Simultaneous heart-liver (SHL) transplants are only a small proportion of overall heart and liver transplantation, they have been increasing in frequency and thus challenge the equitable allocation of organs.RECENT FINDINGS: The incidence of SHL transplants is reviewed along with the outcomes of SHL transplants and their impact on the waitlist, particularly in the context of solitary heart and liver transplantation. The ethical implications, most importantly the principles of utility and equity, of SHL transplant are addressed. In the context of utility, the distinction of a transplant being life-saving versus life-enhancing is investigated. The risk of hepatic decompensation for those awaiting both solitary and combined organ transplantation is an important consideration for the principle of equity. Lastly, the lack of standardization of programmatic approaches to SHL transplant candidates, the national approach to allocation, and the criteria by which programs are evaluated are reviewed.SUMMARY: As with all multiorgan transplantation, SHL transplantation raises ethical issues of utility and equity. Given the unique patient population, good outcomes, lack of alternatives, and overall small numbers, we feel there is continued ethical justification for SHL, but a more standardized nationwide approach to the evaluation, listing, and allocation of organs is warranted.

    View details for DOI 10.1097/MOT.0000000000000806

    View details for PubMedID 32881719

  • Coronary Artery Disease Screening of Asymptomatic Kidney Transplant Candidates: A Web-Based Survey of Practice Patterns in the United States. Kidney medicine Cheng, X. S., Mathew, R. O., Parasuraman, R., Tantisattamo, E., Levea, S., Kapoor, R., Dadhania, D. M., Rangaswami, J. 2020; 2 (4): 505–7

    View details for DOI 10.1016/j.xkme.2020.04.006

    View details for PubMedID 32775996

  • Histologic Case Definition of an Atypical Glomerular Immune-Complex Deposition Following Kidney Transplantation. Kidney international reports Chin, K., Charu, V., O'Shaughnessy, M. M., Troxell, M. L., Cheng, X. S. 2020; 5 (5): 632–42


    Introduction: Immune-complex deposition in the transplanted kidney can present as well-phenotyped recurrent or de novo glomerular disease. However, a subset, herein termed immune-complex glomerulopathy not otherwise specified (ICG-NOS), defies classification. We quantified, categorized, and characterized cases of transplant ICG-NOS occurring at a single US academic medical center.Methods: We retrospectively reviewed our single-institution pathology database (July 2007-July 2018) to identify and categorize all cases of immune-complex deposition in kidney allografts (based on immunofluorescence microscopy). We extracted clinicopathologic and outcome data for ICG-NOS (i.e., immune complex deposition not conforming to any well-characterized glomerular disease entity).Results: Of 104 patients with significant immune deposits, 28 (27%) were classified as ICG-NOS. We created 5 mutually exclusive ICG-NOS categories: Full-house, Quasi-full-house, IgA-rich, C1q-rich, and C1q-poor. Overall, 16 (57%) patients met criteria for definite or possible allograft rejection, including 9 (32%) with antibody-mediated rejection (ABMR), 3 (11%) suspicious for ABMR, 1 (4%) with T-cell-mediated rejection (TCMR), and 9 (32%) with borderline TCMR. After a median follow-up of 2.3 (range, 0.1-14.0) years after biopsy, 7 (25%) allografts had failed and an additional 8 (29%) had persistent renal dysfunction (hematuria, 14%; proteinuria, 21%; and estimated glomerular filtration rate<60 ml/min per 1.73 m2, 11%).Conclusion: In contrast to prior studies, our findings suggest that ICG-NOS is not necessarily a benign glomerular process and that there may be an association between ICG-NOS and alloimmunity. Our immunofluorescence-based classification provides a framework for future studies aiming to further elucidate ICG-NOS pathogenesis and prognosis.

    View details for DOI 10.1016/j.ekir.2020.01.022

    View details for PubMedID 32405585

  • An overview of frailty in kidney transplantation: measurement, management and future considerations. Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association Harhay, M. N., Rao, M. K., Woodside, K. J., Johansen, K. L., Lentine, K. L., Tullius, S. G., Parsons, R. F., Alhamad, T., Berger, J., Cheng, X. S., Lappin, J., Lynch, R., Parajuli, S., Tan, J. C., Segev, D. L., Kaplan, B., Kobashigawa, J., Dadhania, D. M., McAdams-DeMarco, M. A. 2020


    The construct of frailty was first developed in gerontology to help identify older adults with increased vulnerability when confronted with a health stressor. This article is a review of studies in which frailty has been applied to pre- and post-kidney transplantation (KT) populations. Although KT is the optimal treatment for end-stage kidney disease (ESKD), KT candidates often must overcome numerous health challenges associated with ESKD before receiving KT. After KT, the impacts of surgery and immunosuppression represent additional health stressors that disproportionately impact individuals with frailty. Frailty metrics could improve the ability to identify KT candidates and recipients at risk for adverse health outcomes and those who could potentially benefit from interventions to improve their frail status. The Physical Frailty Phenotype (PFP) is the most commonly used frailty metric in ESKD research, and KT recipients who are frail at KT (~20% of recipients) are twice as likely to die as nonfrail recipients. In addition to the PFP, many other metrics are currently used to assess pre- and post-KT vulnerability in research and clinical practice, underscoring the need for a disease-specific frailty metric that can be used to monitor KT candidates and recipients. Although frailty is an independent risk factor for post-transplant adverse outcomes, it is not factored into the current transplant program risk-adjustment equations. Future studies are needed to explore pre- and post-KT interventions to improve or prevent frailty.

    View details for DOI 10.1093/ndt/gfaa016

    View details for PubMedID 32191296

  • Effect of low contrast medium-dose CTA on device sizing and access vessel assessment for TAVR. European journal of radiology Suchá, D., Kino, A., Bogart, K., Molvin, L., Cheng, X. S., Fearon, W. F., Fischbein, M. P., Fleischmann, D. 2020; 124: 108826


    Chronic kidney disease (CKD) is prevalent in transcatheter aortic valve replacement (TAVR) candidates, leading to concerns regarding contrast medium (CM) safety. We evaluated (a) the impact of low-CM imaging on pre-TAVR measurements and (b) postcontrast acute kidney injury (PC-AKI) prevalence after dual-source computed tomography (DSCT) in TAVR candidates.All TAVR candidates with CKD (SCr≥1.5 mg/dL) who underwent weight-based low-CM, low-pitch helical 3rd-generation DSCT in a one-year period were included, and matched to standard-CM, non-CKD controls (N = 50). Image quality (IQ) and pre-TAVR measurement interobserver variability were evaluated. Renal function change and PC-AKI were studied in the entire TAVR cohort, irrespective of scan mode (N = 153).Low-CM in CKD (N = 25) was performed with median 68 mL CM [52-87], 90 kV [80-90] and SCr 1.6 mg/dL [1.5-1.9], and standard-CM without CKD with median 116 mL CM [96-134], 100 kV [90-110] and SCr 1.0 mg/dL [0.9-1.1](P < 0.00). Low-CM IQ was good, though lower compared with standard-CM (P < 0.02). Interobserver measurement reliability was excellent (ICCs>0.85). Interobserver-agreement was lower in low-CM, causing prosthesis size disagreement in 5/25 (kappa-0.73) versus 0/25 with standard-CM (kappa-1.00), and transfemoral eligibility disagreement in 4/25 (kappa-0.68) versus 2/25 (kappa-0.84), respectively. Mean 1-month SCr-change in the low-CM TAVR cohort (N = 35) was -1 % [-12 to +7 %] and in standard-CM (N = 118) 0 % [-8 to +10 %](P > 0.3). PC-AKI occurred in none.Low-CM third-generation-DSCT achieves good IQ in TAVR candidates with CKD, and seems safe, with no apparent renal function deterioration or prevalence of PC-AKI. However, standard-CM protocols in non-CKD patients provide higher measurement reproducibility. Low-CM protocols should therefore be reserved for patients at high risk for PC-AKI.

    View details for DOI 10.1016/j.ejrad.2020.108826

    View details for PubMedID 32000074

  • Physical Performance Testing in Kidney Transplant Candidates at the Top of the Waitlist. American journal of kidney diseases : the official journal of the National Kidney Foundation Cheng, X. S., Myers, J. n., Han, J. n., Stedman, M. R., Watford, D. J., Lee, J. n., Discipulo, K. V., Chan, K. N., Chertow, G. M., Tan, J. C. 2020


    Frailty and poor physical function are associated with adverse kidney transplant outcomes, but how to incorporate this knowledge into clinical practice is uncertain. We studied the association between measured physical performance and clinical outcomes among patients on kidney transplant waitlists.Prospective observational cohort study.We studied consecutive patients evaluated in our Transplant Readiness Assessment Clinic, a top-of-the-waitlist management program, from May 2017 through December 2018 (N=305). We incorporated physical performance testing, including the 6-minute walk test (6MWT) and the sit-to-stand (STS) test, into routine clinical assessments.6MWT and STS test results.Primary - Time to adverse waitlist outcomes (removal from waitlist or death). Secondary - Time to transplantation, time to death.We used linear regression to examine the relationship between clinical characteristics and physical performance test results. We used subdistribution hazards models to examine the association between physical performance test results and outcomes.Median 6MWT and STS results were 393 meters (25th- 75th percentile range 305-455) and 17 repetitions (25th- 75th percentile range 12-21), respectively. Clinical characteristics and Estimated Post-Transplant Survival scores only accounted for 14-21% of the variance in 6MWT/STS results. 6MWT/STS results were associated with adverse waitlist outcomes (adjusted subdistribution hazard ratio [sHR] of 1.42 [95% confidence interval 1.30-1.56 per 50-meter lower in 6MWT and 1.53 [95% confidence interval 1.33-1.75] per 5-repetition lower in STS), and with transplantation (adjusted sHR of 0.80 [95% confidence interval 0.72-0.88] per 50-meter lower in 6MWT and 0.80 [95% confidence interval 0.71-0.89] per 5-repetition lower in STS). Addition of either STS or 6MWT to survival models containing clinical characteristics enhanced fit (likelihood ratio test p<0.001).Single-center observational study. Other measures of global health status (e.g., Fried frailty index or short physical performance battery) were not examined.Among waitlisted kidney transplant candidates with high Kidney Allocation Scores, standardized and easily performed physical performance test results are associated with waitlist outcomes and contain information beyond what is currently routinely collected in clinical practice.

    View details for DOI 10.1053/j.ajkd.2020.04.009

    View details for PubMedID 32512039

  • To Kidney or Not to Kidney: Applying Lessons Learned from the Simultaneous Liver-Kidney Transplant Policy to Simultaneous Heart-Kidney Transplantation. Clinical transplantation Cheng, X. S., Khush, K. K., Wiseman, A. n., Teuteberg, J. n., Tan, J. C. 2020


    As the medical community is increasingly offering transplantation to patients with increasing comorbidity burdens, the number of simultaneous heart-kidney (SHK) transplants is rising in the United States. How to determine eligibility for SHK transplant versus heart transplant alone is an important unknown. In this review, we situate this problem in the broader picture of organ shortage. We critically appraise available literature on outcomes in SHK versus heart transplant alone. We posit staged kidney-after-heart transplantation as a plausible alternative to SHK transplantation and review the pros and cons. Drawing lessons from the field of simultaneous liver-kidney transplant, we argue for an analogous policy for SHK transplant with standardized minimal eligibility criteria and a modified Safety Net provision. The new policy will serve as a starting point for comparing simultaneous versus staged approaches and refining the medical eligibility criteria for SHK.

    View details for DOI 10.1111/ctr.13878

    View details for PubMedID 32279361

  • Simultaneous Coccidioidomycosis and Phaeohyphomycosis in a Kidney Transplant Recipient: A Case Report and Literature Review. Transplant infectious disease : an official journal of the Transplantation Society Puing, A. G., Couture-Cossette, A. n., Wang, A. X., Zygourakis, C. C., Cheng, X. n., Stevens, B. A., Banaei, N. n., Novoa, R. A., Ho, D. Y., Subramanian, A. n. 2020: e13365


    Advances in solid organ transplantation have improved the survival of end-stage organ disease at the expense of an increased risk for opportunistic infections. Unusual clinical presentations and the possibility of concurrent infections make diagnosing invasive fungal infection (IFI) more difficult. Here we present a case of simultaneous vertebral infection caused by Coccidioides immitis-posadasii and subcutaneous phaeohyphomycosis due to Nigrograna mackinnonii in a kidney transplant recipient. The diagnosis of both infections required invasive procedures to obtain tissue and a high index of suspicion that more than one IFI could be present. A multidisciplinary team approach for the management of immunocompromised patients with suspected or diagnosed IFI is warranted.

    View details for DOI 10.1111/tid.13365

    View details for PubMedID 32533741

  • COVID-19 and Kidney Transplantation: Results from the TANGO International Transplant Consortium. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons Cravedi, P. n., Suraj, S. M., Azzi, Y. n., Haverly, M. n., Farouk, S. n., Pérez-Sáez, M. J., Redondo-Pachón, M. D., Murphy, B. n., Florman, S. n., Cyrino, L. G., Grafals, M. n., Venkataraman, S. n., Cheng, X. S., Wang, A. X., Zaza, G. n., Ranghino, A. n., Furian, L. n., Manrique, J. n., Maggiore, U. n., Gandolfini, I. n., Agrawal, N. n., Patel, H. n., Akalin, E. n., Riella, L. V. 2020


    Kidney transplant recipients may be at high risk of developing critical COVID-19 illness due to chronic immunosuppression and comorbidities. We identified hospitalized adult kidney transplant recipients at 12 transplant centers in the US, Italy and Spain who tested positive for COVID-19. Clinical presentation, laboratory values, immunosuppression and treatment strategies were reviewed and predictors of poor clinical outcomes were determined through multivariable analyses. Among 9,845 kidney transplant recipients across centers, 144 were hospitalized due to COVID-19 during the 9-week study period. 65% were male with a mean age of 60 (±12) years, 40% Hispanic and 25% African-American. Prevalent comorbidities included hypertension (95%), diabetes (52%), obesity (49%), heart (28%) and lung (19%) disease. Therapeutic management included antimetabolite withdrawal (68%), calcineurin inhibitor withdrawal (23%), hydroxychloroquine (71%), antibiotics (74%), tocilizumab (13%) and antivirals (14%). During a median follow-up period of 52 days (IQR: 16-66 days), acute kidney injury occurred in 52% cases, respiratory failure requiring intubation in 29%, and mortality was 32%. The 44 patients who died were older, had lower lymphocyte counts and eGFR, higher serum lactate dehydrogenase, procalcitonin and IL-6 levels. In sum, hospitalized kidney transplant recipients with COVID-19 have higher rates of acute kidney injury and mortality.

    View details for DOI 10.1111/ajt.16185

    View details for PubMedID 32649791

  • Coronary Computed Tomography Angiography in Diagnosing Obstructive Coronary Artery Disease in Patients with Advanced Chronic Kidney Disease: A Systematic Review and Meta-Analysis. Cardiorenal medicine Cheng, X. S., Mohanty, S. n., Turner, V. n., Mastrodicasa, D. n., Winther, S. n., Fleischmann, D. n., Tan, J. C., Fearon, W. F. 2020: 1–8


    Coronary computed tomography angiography (CCTA) is emerging as an important noninvasive testing modality for coronary angiography. The performance characteristic of CCTA in patients with advanced kidney disease is unknown.We performed a systematic review and meta-analysis of studies specifically investigating the sensitivity and specificity of CCTA compared to coronary angiogram as a reference standard in patients with advanced kidney disease, defined as dialysis dependence or nearing kidney transplantation. Two independent investigators assessed studies for inclusion/exclusion, quality, and characteristics, while a third investigator adjudicated.We identified 4 studies including a total of 217 patients, of whom 159 were dialysis dependent. Three of the 4 studies had a high risk of bias in patient selection and study flow, while 1 study rated low in all areas of bias. The studies were heterogeneous in their patient selection and CCTA protocol but consistent in their definition of obstructive coronary artery disease. The pooled sensitivity and specificity for CCTA were 0.96 (0.87-0.99) and 0.66 (0.57-0.74), respectively. When we restricted the analysis to dialysis-dependent patients, the pooled sensitivity and specificity for CCTA were 0.99 (0.74-1.00) and 0.67 (0.49-0.82), respectively.Based on limited data, CCTA appears to have comparable sensitivity but lower specificity relative to the non-kidney disease population.

    View details for DOI 10.1159/000510402

    View details for PubMedID 33321489

  • Recurrence of FSGS after Kidney Transplantation in Adults. Clinical journal of the American Society of Nephrology : CJASN Uffing, A. n., Pérez-Sáez, M. J., Mazzali, M. n., Manfro, R. C., Bauer, A. C., de Sottomaior Drumond, F. n., O'Shaughnessy, M. M., Cheng, X. S., Chin, K. K., Ventura, C. G., Agena, F. n., David-Neto, E. n., Mansur, J. B., Kirsztajn, G. M., Tedesco-Silva, H. n., Neto, G. M., Arias-Cabrales, C. n., Buxeda, A. n., Bugnazet, M. n., Jouve, T. n., Malvezzi, P. n., Akalin, E. n., Alani, O. n., Agrawal, N. n., La Manna, G. n., Comai, G. n., Bini, C. n., Muhsin, S. A., Riella, M. C., Hokazono, S. R., Farouk, S. S., Haverly, M. n., Mothi, S. S., Berger, S. P., Cravedi, P. n., Riella, L. V. 2020


    FSGS recurrence after kidney transplantation is a major risk factor for graft loss. However, the natural history, clinical predictors, and response to treatment remain unclear because of small sample sizes and poor generalizability of single-center studies, and disease misclassification in registry-based studies. We therefore aimed to determine the incidence, predictors, and treatment response of recurrent FSGS in a large cohort of kidney transplant recipients.The Post-Transplant Glomerular Disease (TANGO) project is an observational, multicenter, international cohort study that aims to investigate glomerular disease recurrence post-transplantation. Transplant recipients were screened for the diagnosis of idiopathic FSGS between 2005 and 2015 and details were recorded about the transplant, clinical outcomes, treatments, and other risk factors.Among 11,742 kidney transplant recipients screened for FSGS, 176 had a diagnosis of idiopathic FSGS and were included. FSGS recurred in 57 patients (32%; 95% confidence interval [95% CI], 25% to 39%) and 39% of them lost their graft over a median of 5 (interquartile range, 3.0-8.1) years. Multivariable Cox regression revealed a higher risk for recurrence with older age at native kidney disease onset (hazard ratio [HR], 1.37 per decade; 95% CI, 1.09 to 1.56). Other predictors were white race (HR, 2.14; 95% CI, 1.08 to 4.22), body mass index at transplant (HR, 0.89 per kg/m2; 95% CI, 0.83 to 0.95), and native kidney nephrectomies (HR, 2.76; 95% CI, 1.16 to 6.57). Plasmapheresis and rituximab were the most frequent treatments (81%). Partial or complete remission occurred in 57% of patients and was associated with better graft survival.Idiopathic FSGS recurs post-transplant in one third of cases and is associated with a five-fold higher risk of graft loss. Response to treatment is associated with significantly better outcomes but is achieved in only half of the cases.

    View details for DOI 10.2215/CJN.08970719

    View details for PubMedID 31974287

  • Toward telemedicine-compatible physical functioning assessments in kidney transplant candidates. Clinical transplantation Watford, D. J., Cheng, X. S., Han, J. n., Stedman, M. R., Chertow, G. M., Tan, J. C. 2020: e14173


    Frailty is associated with adverse kidney transplant outcomes and can be assessed by subjective and objective metrics. There is increasing recognition of the value of metrics obtainable remotely. We compared the self-reported SF-36 physical functioning subscale score (SF-36 PF) with in-person physical performance tests (6-minute walk and sit-to-stand) in a prospective cohort of kidney transplant candidates. We assessed each metric's ability to predict time to the composite outcome of waitlist removal or death, censoring at transplant. We built time-dependent receiver operating characteristic curves and calculated the area under the curve [AUC(t)] at 1 year, using bootstrapping for internal validation. In 199 patients followed for a median of 346 days, 41 reached the composite endpoint. Lower SF-36 PF scores were associated with higher risk of waitlist removal/death, with every 10-point decrease corresponding to a 16% increase in risk. All models showed an AUC(t) of 0.83-0.84 that did not contract substantially after internal validation. Among kidney transplant candidates, SF-36 PF, obtainable remotely, can help to stratify the risk of waitlist removal or death, and may be used as a screening tool for poor physical functioning in ongoing candidate evaluation, particularly where travel, increasing patient volume, or other restrictions challenge in-person assessment.

    View details for DOI 10.1111/ctr.14173

    View details for PubMedID 33247983

  • Implications of Frailty for Peritransplant Outcomes in Kidney Transplant Recipients. Current transplantation reports Cheng, X. S., Lentine, K. L., Koraishy, F. M., Myers, J., Tan, J. C. 2019; 6 (1): 16–25


    Purpose of Review: Research over the past few decades points to the importance of frailty, or the lack of physiologic reserve, in the natural history of chronic diseases and in modifying the impact of potential interventions. End-stage kidney disease (ESKD) and the intervention of kidney transplantation are no exception. We review the recent epidemiologic and cohort-based evidence on the association between frailty and kidney transplant outcomes and provide a framework of questions with which to approach future research endeavors and clinical practice.Recent Findings: Frailty in kidney transplant candidates can be measured in numerous ways, including descriptive phenotype, description scores, functional testing, and surrogate measures. Regardless of the metric, the presence of frailty is strongly associated with inferior pre- and posttransplant outcomes compared to the absence of frailty. However, some frail patients with ESKD can benefit from transplant over chronic dialysis. Evidence-based approaches for identifying frail ESKD patients who can benefit from transplant over dialysis, with acceptable posttransplant outcomes, are lacking. Interventional trials to improve frailty and physical function before transplant (prehabilitation) and after transplant (rehabilitation) are also lacking.Conclusion: Frailty is increasingly recognized as highly relevant to peritransplant outcomes, but more work is needed to: 1) tailor management to the unique needs of frail patients, both pre- and posttransplant; 2) define phenotypes of frail patients who are expected to benefit from transplant over dialysis; and 3) develop interventions to reverse frailty, both pre- and post-transplant.

    View details for DOI 10.1007/s40472-019-0227-z

    View details for PubMedID 31131186

  • Perceptions and Practices Regarding Frailty in Kidney Transplantation: Results of A National Survey. Transplantation McAdams-DeMarco, M. A., Rasmussen, S. E., Chu, N. M., Agoons, D. n., Parsons, R. F., Alhamad, T. n., Johansen, K. L., Tullius, S. G., Lynch, R. n., Harhay, M. N., Rao, M. K., Berger, J. n., Cooper, M. n., Tan, J. C., Cheng, X. S., Woodside, K. J., Parajuli, S. n., Lentine, K. L., Kaplan, B. n., Segev, D. L., Kobashigawa, J. A., Dadhania, D. n. 2019


    Given the potential utility of frailty, a clinical phenotype of decreased physiologic reserve and resistance to stressors, to predict post-kidney transplant (KT) outcomes, we sought to understand the perceptions and practices regarding frailty measurement in US KT programs.Surveys were emailed to American Society of Transplantation Kidney/Pancreas Community of Practice members and 202 US transplant programs (11/2017-4/2018). Program characteristics were gleaned from SRTR.The 133 responding programs (response rate=66%) represented 77% of adult KTs and 79% of adult KT candidates in the US. Respondents considered frailty to be a useful concept in evaluating candidacy (99%) and endorsed a need to develop a frailty measurement specific to KT (92%). Frailty measurement was more common during candidacy evaluation (69%) than during KT admission (28%). Of the 202 programs, 38% performed frailty assessments in all candidates while 23% performed assessments only for older candidates. There was heterogeneity in the frailty assessment method; 18 different tools were utilized to measure frailty. The most common tool was a timed walk test (19%); 67% reported performing >1 tool. Among programs that measure frailty, 53% reported being less likely to list frail patients for KT.Among US KT programs, frailty is recognized as a clinically relevant construct and is commonly measured at evaluation. However, there is considerably heterogeneity in the tools used to measure frailty. Efforts to identify optimal measurement of frailty using either an existing or novel tool and subsequent standardization of its measurement and application across KT programs should be considered.

    View details for DOI 10.1097/TP.0000000000002779

    View details for PubMedID 31343576

  • A large, international study on post-transplant glomerular diseases: the TANGO project BMC NEPHROLOGY Uffing, A., Jose Perez-Saez, M., La Manna, G., Comai, G., Fischman, C., Farouk, S., Manfro, R., Bauer, A., Lichtenfels, B., Mansur, J. B., Tedesco-Silva, H., Kirsztajn, G. M., Manonelles, A., Bestard, O., Riella, M., Hokazono, S., Arias-Cabrales, C., David-Neto, E., Ventura, C., Akalin, E., Mohammed, O., Khankin, E. V., Safa, K., Malvezzi, P., O'Shaughnessy, M., Cheng, X. S., Cravedi, P., Riella, L. V. 2018; 19: 229


    Long-term outcomes in kidney transplantation (KT) have not significantly improved during the past twenty years. Despite being a leading cause of graft failure, glomerular disease (GD) recurrence remains poorly understood, due to heterogeneity in disease pathogenesis and clinical presentation, reliance on histopathology to confirm disease recurrence, and the low incidence of individual GD subtypes. Large, international cohorts of patients with GD are urgently needed to better understand the disease pathophysiology, predictors of recurrence, and response to therapy.The Post-TrANsplant GlOmerular Disease (TANGO) study is an observational, multicenter cohort study initiated in January 2017 that aims to: 1) characterize the natural history of GD after KT, 2) create a biorepository of saliva, blood, urine, stools and kidney tissue samples, and 3) establish a network of patients and centers to support novel therapeutic trials. The study includes 15 centers in America and Europe. Enrollment is open to patients with biopsy-proven GD prior to transplantation, including IgA nephropathy, membranous nephropathy, focal and segmental glomerulosclerosis, atypical hemolytic uremic syndrome, dense-deposit disease, C3 glomerulopathy, complement- and IgG-positive membranoproliferative glomerulonephritis or membranoproliferative glomerulonephritis type I-III (old classification). During phase 1, patient data will be collected in an online database. The biorepository (phase 2) will involve collection of samples from patients for identification of predictors of recurrence, biomarkers of disease activity or response to therapy, and novel pathogenic mechanisms. Finally, through phase 3, we will use our multicenter network of patients and centers to launch interventional studies.Most prior studies of post-transplant GD recurrence are single-center and retrospective, or rely upon registry data that frequently misclassify the cause of kidney disease. Systematically determining GD recurrence rates and predictors of clinical outcomes is essential to improving post-transplant outcomes. Furthermore, accurate molecular phenotyping and biomarker development will allow better understanding of individual GD pathogenesis, and potentially identify novel drug targets for GD in both native and transplanted kidneys. The TANGO study has the potential to tackle GD recurrence through a multicenter design and a comprehensive biorepository.

    View details for PubMedID 30208881

  • Native Kidney Cytomegalovirus Nephritis and Cytomegalovirus Prostatitis in a Kidney Transplant Recipient. Transplant infectious disease : an official journal of the Transplantation Society Tan, S. K., Cheng, X. S., Kao, C., Weber, J., Pinsky, B. A., Gill, H. S., Busque, S., Subramanian, A. K., Tan, J. C. 2018: e12998


    We present a case of cytomegalovirus (CMV) native kidney nephritis and prostatitis in a CMV D+/R- kidney transplant recipient who had completed six months of CMV prophylaxis four weeks prior to the diagnosis of genitourinary CMV disease. The patient had a history of benign prostatic hypertrophy and urinary retention that required self-catheterization to relieve high post-voiding residual volumes. At 7 months post-transplant, he was found to have a urinary tract infection, moderate hydronephrosis of the transplanted kidney, and severe hydroureteronephrosis of the native left kidney and ureter, and underwent native left nephrectomy and transurethral resection of the prostate. Histopathologic examination of kidney and prostate tissue revealed CMV inclusions consistent with invasive CMV disease. This case highlights that CMV may extend beyond the kidney allograft to involve other parts of the genitourinary tract, including the native kidneys and prostate. Furthermore, we highlight the tissue-specific risk factors that preceded CMV tissue invasion. In addition to concurrent diagnoses, health care providers should have a low threshold for considering late-onset CMV disease in high-risk solid organ transplant recipients presenting with signs and symptoms of genitourinary tract pathology. This article is protected by copyright. All rights reserved.

    View details for PubMedID 30203504

  • Underutilization of Hepatitis C Virus Seropositive Donor Kidneys in the United States in the Current Opioid Epidemic and Direct-Acting Antiviral Era. Diseases (Basel, Switzerland) Li, A. A., Cholankeril, G., Cheng, X. S., Tan, J. C., Kim, D., Toll, A. E., Nair, S., Ahmed, A. 2018; 6 (3)


    In recent years, the opioid epidemic and new hepatitis C virus (HCV) treatments have changed the landscape of organ procurement and allocation. We studied national trends in solid organ transplantation (2000⁻2016), focusing on graft utilization from HCV seropositive deceased donors in the pre-2014 (2000⁻2013) versus current (2014⁻2016) eras with a retrospective analysis of the United Network for Organ Sharing database. During the study period, HCV seropositive donors increased from 181 to 661 donors/year. The rate of HCV seropositive donor transplants doubled from 2014 to 2016. Heart and lung transplantation data were too few to analyze. A higher number of HCV seropositive livers were transplanted into HCV seropositive recipients during the current era: 374 versus 124 liver transplants/year. Utilization rates for liver transplantation reached parity between HCV seropositive and non-HCV donors. While the number of HCV seropositive kidneys transplanted to HCV seropositive recipients increased from 165.4 to 334.7 kidneys/year from the pre-2014 era to the current era, utilization rates for kidneys remained lower in HCV seropositive than in non-HCV donors. In conclusion, relative underutilization of kidneys from HCV seropositive versus non-HCV donors has persisted, in contrast to trends in liver transplantation.

    View details for PubMedID 29996536

  • Comparing Simultaneous Liver-Kidney Transplant Strategies: A Modified Cost-Effectiveness Analysis. Transplantation Cheng, X. S., Kim, W. R., Tan, J. C., Chertow, G. M., Goldhaber-Fiebert, J. 2018


    BACKGROUND: The proportion of patients with kidney failure at time of liver transplantation is at an historic high in the United States. The optimal timing of kidney transplantation with respect to the liver transplant is unknown.METHODS: We used a modified cost-effectiveness analysis to compare four strategies: the old system ("pre-OPTN"), the new Organ Procurement Transplant Network (OPTN) system since August 10, 2017 ("OPTN"), and two strategies which restrict simultaneous liver-kidney transplants ("safety net" and "stringent"). We measured "cost" by deployment of deceased donor kidneys (DDKs) to liver transplant recipients and effectiveness by life years (LYs) and quality-adjusted life years (QALYs) in liver transplant recipients. We validated our model against Scientific Registry for Transplant Recipients data.RESULTS: The OPTN, safety net and stringent strategies were on the efficient frontier. By rank order, OPTN > safety net > stringent strategy in terms of LY, QALY and DDK deployment. The pre-OPTN system was dominated, or outperformed, by all alternative strategies. The incremental LY per DDK between the strategies ranged from 1.30 to 1.85. The incremental QALY per DDK ranged from 1.11 to 2.03.CONCLUSION: These estimates quantify the "organ"-effectiveness of various kidney allocation strategies for liver transplant candidates. The OPTN system will likely deliver better liver transplant outcomes at the expense of more frequent deployment of DDKs to liver transplant recipients.

    View details for PubMedID 29554056

  • Prehabilitation for Kidney Transplant Candidates: Is it Time? Clinical transplantation Cheng, X. S., Myers, J. N., Chertow, G. M., Rabkin, R., Chan, K. N., Chen, Y., Tan, J. C. 2017


    Many patients become frail with diminished cardiorespiratory fitness while awaiting kidney transplantation. Frailty and poor fitness powerfully predict mortality, transplant graft survival, and health care utilization after kidney transplantation. Efforts to intervene with post-transplant physical therapy have been met with limited success, in large part due to high study drop-out. We reviewed the literature on chronic kidney disease and exercise to propose a clinical framework for physical therapy interventions to improve fitness, scheduled for before the transplant. This framework may lead to better patient retention and compliance, and thus demonstrate better efficacy in mitigating the effects of frailty and poor fitness after kidney transplantation. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1111/ctr.13020

    View details for PubMedID 28564126

  • Home Dialysis in the Prospective Payment System Era. Journal of the American Society of Nephrology Lin, E., Cheng, X. S., Chin, K., Zubair, T., Chertow, G. M., Bendavid, E., Bhattacharya, J. 2017


    The ESRD Prospective Payment System introduced two incentives to increase home dialysis use: bundling injectable medications into a single payment for treatment and paying for home dialysis training. We evaluated the effects of the ESRD Prospective Payment System on home dialysis use by patients starting dialysis in the United States from January 1, 2006 to August 31, 2013. We analyzed data on dialysis modality, insurance type, and comorbidities from the United States Renal Data System. We estimated the effect of the policy on home dialysis use with multivariable logistic regression and compared the effect on Medicare Parts A/B beneficiaries with the effect on patients with other types of insurance. The ESRD Prospective Payment System associated with a 5.0% (95% confidence interval [95% CI], 4.0% to 6.0%) increase in home dialysis use by the end of the study period. Home dialysis use increased by 5.8% (95% CI, 4.3% to 6.9%) among Medicare beneficiaries and 4.1% (95% CI, 2.3% to 5.4%) among patients covered by other forms of health insurance. The difference between these groups was not statistically significant (1.8%; 95% CI, -0.2% to 3.8%). Conversely, in both populations, the training add-on did not associate with increases in home dialysis use beyond the effect of the policy. The ESRD Prospective Payment System bundling, but not the training add-on, associated with substantial increases in home dialysis, which were identical for both Medicare and non-Medicare patients. These spill-over effects suggest that major payment changes in Medicare can affect all patients with ESRD.

    View details for DOI 10.1681/ASN.2017010041

    View details for PubMedID 28490435

  • Utility in Treating Kidney Failure in End-Stage Liver Disease With Simultaneous Liver-Kidney Transplantation TRANSPLANTATION Cheng, X. S., Stedman, M. R., Chertow, G. M., Kim, W. R., Tan, J. C. 2017; 101 (5): 1111-1119


    Simultaneous liver-kidney (SLK) transplantation plays an important role in treating kidney failure in patients with end-stage liver disease. It used 5% of deceased donor kidney transplanted in 2015. We evaluated the utility, defined as posttransplant kidney allograft lifespan, of this practice.Using data from the Scientific Registry of Transplant Recipients, we compared outcomes for all SLK transplants between January 1, 1995, and December 3, 2014, to their donor-matched kidney used in kidney-alone (Ki) or simultaneous pancreas kidney (SPK) transplants. Primary outcome was kidney allograft lifespan, defined as the time free from death or allograft failure. Secondary outcomes included death and death-censored allograft failure. We adjusted all analyses for donor, transplant, and recipient factors.The adjusted 10-year mean kidney allograft lifespan was higher in Ki/SPK compared with SLK transplants by 0.99 years in the Model for End-stage Liver Disease era and 1.71 years in the pre-Model for End-stage Liver Disease era. Death was higher in SLK recipients relative to Ki/SPK recipients: 10-year cumulative incidences 0.36 (95% confident interval 0.33-0.38) versus 0.19 (95% confident interval 0.17-0.21).SLK transplantation exemplifies the trade-off between the principles of utility and medical urgency. With each SLK transplantation, about 1 year of allograft lifespan is traded so that sicker patients, that is, SLK transplant recipients, are afforded access to the organ. These data provide a basis against which benefits derived from urgency-based allocation can be measured.

    View details for DOI 10.1097/TP.0000000000001491

    View details for PubMedID 28437790

  • Validating identification of patients with small vessel vasculitis, with or without renal involvement, using administrative healthcare records. Clinical nephrology O'Shaughnessy, M. M., Cheng, X. S., Montez-Rath, M. E., Lafayette, R. A., Winkelmayer, W. C. 2017; 87 (2017) (3): 159-162

    View details for DOI 10.5414/CN109035

    View details for PubMedID 28102817

  • Donation, Not Disease! A Multiple-Hit Hypothesis on Development of Post-Donation Kidney Disease. Current transplantation reports Cheng, X. S., Glassock, R. J., Lentine, K. L., Chertow, G. M., Tan, J. C. 2017; 4 (4): 320–26


    The risks following living kidney donation has been the subject of rigorous investigation in the past several decades. How to utilize the burgeoning new knowledge base to better the risk assessment, education, and health maintenance of donors is unclear. We review the physiologic and epidemiologic evidences on the post-donation state and submit a multiple-hit hypothesis to reconcile the finite elevation in risk of kidney disease after donation with the benign course of most kidney donors.The risk of end-stage kidney disease is higher in kidney donors compared to similarly healthy non-kidney donors. Nonetheless, post-donation kidney disease is uncommon and arises mostly in the setting of other "hits"-either a "first hit" present at birth or a "second hit" acquired later in life.The transplant community's focus should be directed toward (1) personalized risk assessment to inform consent before donation and (2) preventing and treating development of "second hits" following kidney donation.

    View details for PubMedID 29201600

  • Management of Renal Failure in End-Stage Liver Disease: A Critical Appraisal LIVER TRANSPLANTATION Cheng, X. S., Tan, J. C., Kim, W. R. 2016; 22 (12): 1710-1719


    Renal failure is a late consequence of end-stage liver disease (ESLD). Even with liver transplantation, pretransplant renal impairment remains a strong predictor of posttransplant mortality. This review seeks to summarize and critically appraise common therapies used in this setting, including pharmacologic agents, procedures (transjugular intrahepatic portosystemic shunt, renal replacement therapy), and simultaneous liver-kidney transplantation. More experimental extracorporal modalities, eg, albumin dialysis or bioartificial livers, will not be discussed. A brief discussion on the definition and pathophysiologic underpinnings of renal failure in ESLD will be held at the beginning to lay the groundwork for the main section. Liver Transplantation 22 1710-1719 2016 AASLD.

    View details for DOI 10.1002/lt.24609

    View details for Web of Science ID 000389079500011

    View details for PubMedID 27875032

  • An electronic alert to decrease Kayexalate ordering RENAL FAILURE Leaf, D. E., Cheng, X. S., Sanders, J. L., Mendu, M., Schiff, G. D., Mount, D. B., Bazari, H. 2016; 38 (10): 1752-1754


    Important safety concerns have recently emerged regarding the use of sodium polystyrene sulfonate (Kayexalate), a cation-exchange resin commonly used for the treatment of hyperkalemia. We implemented an electronic alert system at a tertiary care academic medical center to warn providers of the safety concerns of Kayexalate. We assessed the number of Kayexalate prescriptions per month, as well as the number of grams of Kayexalate ordered per month, one year before versus one year after implementing the alert. The mean (±SD) number of Kayexalate orders decreased from 123 (±12) to 76 (±14) orders/month (38% absolute reduction, p < 0.001) after implementing the alert. Additionally, the mean (±SD) amount of Kayexalate prescribed decreased from 3332 (±329) to 1885 (±358) g/month (43% absolute reduction, p < 0.001). We conclude that an electronic alert is an effective tool to decrease Kayexalate ordering.

    View details for DOI 10.1080/0886022X.2016.1185353

    View details for Web of Science ID 000392430900029

    View details for PubMedID 27183825

    View details for PubMedCentralID PMC5114173

  • Beyond the last battle: a viewpoint from the frontiers of transplantation. American journal of kidney diseases : the official journal of the National Kidney Foundation Cheng, X. S. 2015; 66 (1): A15–7

    View details for DOI 10.1053/j.ajkd.2015.05.006

    View details for PubMedID 26111908

  • The Root of This Evil: Microangiopathic Hemolytic Anemia and Renal Failure AMERICAN JOURNAL OF MEDICINE Cheng, X. S., Adusumalli, S., Singh, H., DePasse, J. W., Smith, R., Haupert, G. T. 2015; 128 (1): 21–23

    View details for DOI 10.1016/j.amjmed.2014.08.021

    View details for Web of Science ID 000347030100020

    View details for PubMedID 25218936

  • Enhanced Creatinine and Estimated Glomerular Filtration Rate Reporting to Facilitate Detection of Acute Kidney Injury AMERICAN JOURNAL OF CLINICAL PATHOLOGY Baron, J. M., Cheng, X. S., Bazari, H., Bhan, I., Lofgren, C., Jaromin, R. T., Lewandrowski, K. B., Dighe, A. S. 2015; 143 (1): 42–49


    While acute kidney injury (AKI) can be diagnosed based on specified increases in a patient's plasma creatinine level, standard creatinine reporting methods typically only flag creatinine results as abnormal when outside the reference range and often fail to identify rising creatinine values indicative of AKI. Here, we evaluate the impact of this limitation in standard creatinine reporting and develop and implement an enhanced creatinine reporting algorithm.We evaluated 59,712 plasma creatinine results collected over approximately 3 months, using computational simulations and statistical analyses.Our analyses demonstrated that 29% of creatinine results substantially increased over the patient's baseline and concerning for AKI remained within the normal reference range. These concerning results would not be flagged as abnormal using standard reporting. Likewise, we found that simple delta checks are also insensitive at AKI detection. To improve creatinine reporting, we developed and implemented an algorithm within our laboratory information system to alert clinicians to rising creatinine results, which we describe in this report.While both creatinine reference limits and simple delta checks are insensitive for AKI identification, a simple algorithm can be implemented within a common laboratory information system to enhance AKI identification.

    View details for DOI 10.1309/AJCP05XBCQPHTLGQ

    View details for Web of Science ID 000346757900008

    View details for PubMedID 25511141

  • Inhibitory Interactions between BK and JC Virus among Kidney Transplant Recipients JOURNAL OF THE AMERICAN SOCIETY OF NEPHROLOGY Cheng, X. S., Bohl, D. L., Storch, G. A., Ryschkewitsch, C., Gaudreault-Keener, M., Major, E. O., Randhawa, P., Hardinger, K. L., Brennan, D. C. 2011; 22 (5): 825–31


    BK and JC polyomaviruses can reactivate after transplantation, causing renal dysfunction and graft loss. The incidence of JC reactivation after renal transplant is not well understood. Here, we characterized JC reactivation using samples collected during the first year after transplantation from 200 kidney recipients. We detected BK and JC viruses in the urine of 35 and 16% of transplant recipients, respectively. The median viral load in the urine was 400 times higher for BK virus than JC virus. The presence of BK viruria made concurrent JC viruria less likely: JC viruria was detected in 22% of non-BK viruric recipients compared with 4% of BK viruric recipients (P=0.001). The co-detection rate was 1.5%, which is less than the expected 5.6% if reactivation of each virus was independent (P=0.001). We did not observe JC viremia, JC nephropathy, or progressive multifocal leukoencephalopathy. The onset of JC viruria was associated with donor, but not recipient, JC-specific antibody in a titer-dependent fashion and inversely associated with donor and recipient BK-specific antibody. Donor and recipient JC seropositivity did not predict BK viruria or viremia. In conclusion, among renal transplant recipients, infection with one polyomavirus inversely associates with infection with the other.

    View details for DOI 10.1681/ASN.2010080877

    View details for Web of Science ID 000291519500009

    View details for PubMedID 21511831

    View details for PubMedCentralID PMC3269895