
Bekir Tanriover
- Professor, Medicine - (Clinical Scholar Track)
- Chief, Division of Nephrology
Contact
- (520) 626-6453
- AHSC, Rm. 2301
- TUCSON, AZ 85724-5099
- btanriover@arizona.edu
Awards
- COM-T Mentoring Award
- COM-Tucson, Spring 2025
Interests
No activities entered.
Courses
No activities entered.
Scholarly Contributions
Chapters
- Qannus, A., Bracamonte, E., & Tanriover, B. (2022). Isolated Vascular Lesions in Renal Allograft Biopsy: How Do I Treat it?. In Case based renal transplantation.. doi:10.1007/978-3-031-13569-9_39More infoIsolated vascular lesion (IvL) is an infrequent finding in allograft kidney biopsies, but it poses a challenge in terms of understanding its underlying pathophysiology and treatment decisions. In the following case, a discussion will cover these challenges and answer some related questions in light of recently published literature.
Journals/Publications
- Anand, P., Woodside, K., Singh, N., Alhamad, T., Bloom, R., Gupta, G., Singer, G., Doshi, M., Dadhania, D., Tanriover, B., Parsons, R., Wagner, C., Xiao, H., Lentine, K., Adey, D., Baliga, R., Bhupathi, S., Byford, H., Lee, K., , Niederhaus, S., et al. (2024). Transition of Care of Stable Kidney Transplant Patients to Referring Nephrologists: A Survey of U.S. Transplant Program Staff. Clinical Transplantation, 38(11). doi:10.1111/ctr.15484More infoBackground and Objectives: We conducted a national survey to assess the opinions and experiences of transplant center staff related to processes of care graduation. Methods: Following IRB approval, medical staff at U.S. adult kidney transplant programs were surveyed using the Qualtrics survey platform (4/5/2022–10/05/2022). Respondents were invited via email and listservs of professional societies. If > 1 survey was submitted for a program, a selection hierarchy was utilized (e.g., prioritizing nephrologists’ responses). Results: Respondents provided data from 46.7% of active programs (N = 92), representing 67% of the national kidney transplant volume. Most respondents (70%) were nephrologists. Full graduation to referring nephrologists was reported by 39% of transplant programs, with an additional 48% reporting partial graduation with ongoing co-management. Rationales for graduation were multifactorial, most commonly including patient travel distance (64%), maintenance of referral base (58%), continuity of care (58%), and center and/or patient burden (54%). Common reasons cited by programs for postgraduation return of care to the transplant center included worsening renal function (82%), malignancy (66%), opportunistic infection (63%), limited local nephrologist availability (60%), and pregnancy planning (57%). Additional coordinators and clinic staff were cited as needed to make transplant center perpetual care feasible by 78% of programs, with 71% stating that more clinicians are needed, while half thought more physical space or telemedicine are required. Conclusions: Graduation of kidney transplant patients is common, with half of programs using a joint-care approach and another third reporting full return of care to the referring nephrologist. Expanded opportunities related to transplant care for the broad nephrology community are essential.
- Azhar, A., Defor, E., Bandyopadhyay, D., Kamal, L., Tanriover, B., & Gupta, G. (2024). "Long-term effects of center volume on transplant outcomes in adult kidney transplant recipients". PLoS ONE, 19(6). doi:10.1371/journal.pone.0301425More infoBackground The influence of center volume on kidney transplant outcomes is a topic of ongoing debate. In this study, we employed competing risk analyses to accurately estimate the marginal probability of graft failure in the presence of competing events, such as mortality from other causes with long-term outcomes. The incorporation of immunosuppression protocols and extended follow-up offers additional insights. Our emphasis on long-term follow-up aligns with biological considerations where competing risks play a significant role. Methods We examined data from 219,878 adult kidney-only transplantations across 256 U.S. transplant centers (January 2001-December 2015) sourced from the Organ Procurement and Transplantation Network registry. Centers were classified into quartiles by annual volume: low (Q1 = 28), medium (Q2 = 75), medium-high (Q3 = 121), and high (Q4 = 195). Our study investigated the relationship between center volume and 5-year outcomes, focusing on graft failure and mortality. Sub-population analyses included deceased donors, living donors, diabetic recipients, those with kidney donor profile index >85%, and re-transplants from deceased donors. Results Adjusted cause-specific hazard ratios (aCHR) for Five-Year Graft Failure and Patient Death were examined by center volume, with low-volume centers as the reference standard (aCHR: 1.0). In deceased donors, medium-high and high-volume centers showed significantly lower cause-specific hazard ratios for graft failure (medium-high aCHR = 0.892, p
- Ergün, M., Sandıkçı, B., Tanrıöver, B., & Ulukuş, M. (2024). Cytomegalovirus matching in deceased donor kidney allocation: Results from a U.S. National simulation model. Transplantation Direct, 10(6). doi:10.1097/txd.0000000000001622More infoBackground. Cytomegalovirus (CMV) infects >60% of adults and can pose an independent risk factor for allograft loss and mortality in solid organ transplant recipients. The purpose of this study is to evaluate the impact of a nationwide implementation of CMV seromatching (donor/recipient: D−/R− and D+/R+) in the U.S. deceased donor kidney allocation system (KAS). Methods. Adult candidates on the U.S. kidney-only transplant waiting list and deceased donor kidneys offered to the U.S. transplant centers were considered. A discrete-event simulation model, simulating the pre-COVID-19 period from January 1, 2015, to January 1, 2018, was used to compare the performances of currently employed KAS-250 policy (without CMV matching) to various simulated CMV matching policies parameterized by calculated panel reactive antibody exception threshold. Outcomes included CMV serodistribution, waiting time, access to transplantation among various groups, transplant rate, graft survival, kidney discard rate, and antigen-mismatch distribution, stratified by CMV serostatus. Results. CMV matching policy with a calculated panel reactive antibody exception threshold of 50% (namely, the CMV“>50%” policy) strikes a better balance between benefits and drawbacks of CMV matching. Compared with KAS-250, CMV“>50%” reduced CMV high-risk (D+/R−) transplants (6.1% versus 18.1%) and increased CMV low-risk (D−/R−) transplants (27.2% versus 13.1%); increased transplant rate for CMV R− patients (11.54 versus 12.57) but decreased for R+ patients (10.68 versus 10.48), yielding an increase in aggregate (11.09 versus 10.94); and reduced mean time to transplantation (by 6 wk); and reduced kidney discard rate (25.7% versus 26.2%). Conclusions. Our findings underscore the feasibility and potential advantages of a nationwide CMV seromatching policy in kidney transplantation.
- Kirkman, D. L., Kidd, J. M., Carbone, S., Pontinha, V. M., Tanriover, B., Kumar, D., & Gupta, G. (2024). Frailty and Prehabilitation: Navigating the Road to a Successful Transplant. Journal of the American Society of Nephrology : JASN, 35(11), 1607-1609.
- Kirkman, D., Kidd, J., Carbone, S., Pontinha, V., Tanriover, B., Kumar, D., & Gupta, G. (2024). Frailty and Prehabilitation Navigating the Road to a Successful Transplant. Journal of the American Society of Nephrology, 35(11). doi:10.1681/asn.0000000000000485
- Lubetzky, M., Chauhan, K., Alrata, L., Dubrawka, C., Abuazzam, F., Abdulkhalek, S., Abdulhadi, T., Yaseen Alsabbagh, D., Singh, N., Lentine, K. L., Tanriover, B., & Alhamad, T. (2024). Management of Failing Kidney and Pancreas Transplantations. Advances in kidney disease and health, 31(5), 476-482.More infoSurvival rates for allografts have improved over the last 2 decades, yet failing allografts remains a challenge in the field of transplant. The risks of mortality and morbidity associated with failed allografts are compounded by infectious complications and metabolic abnormalities, emphasizing the need for a standardized approach to management. Management of failing allografts lacks consensus, highlighting the need for unified protocols to guide treatment protocols and minimize risks with postdialysis initiation. The decision to wean off immunosuppression depends on various factors, including living donor availability and infectious risks, necessitating improved coordination of care and a standard guideline. Treatment of failed pancreas focuses on glycemic control, with insulin as the mainstay, while considering surgical interventions such as graft pancreatectomy in advanced symptomatic cases. Navigating the complexities of failed allograft management demands a multidisciplinary approach and standardized stepwise protocol. Addressing the gaps in management plans for failing allografts and employing a systematic approach to transplant decisions will enhance patient outcomes and facilitate informed decision-making.
- Singh, N., Anand, P. M., Gupta, G., Sawinski, D., Fix, O., Adey, D., Akalin, E., Zayas, C., Dadhania, D., Doshi, M., Cibrik, D., Gupta, M., Parsons, R., Leca, N., Santos, R. D., Concepcion, B. P., Nishio Lucar, A. G., Ong, S., Sridhar, V. S., , Parajuli, S., et al. (2024). Should Transplant Nephrology Pursue Recognition from the Accreditation Council for Graduate Medical Education (ACGME)?. Clinical journal of the American Society of Nephrology : CJASN, 19(8), 1051-1060.More infoKidney transplant is not only the best treatment for patients with advanced kidney disease but it also reduces health care expenditure. The management of transplant patients is complex as they require special care by transplant nephrologists who have expertise in assessing transplant candidates, understand immunology and organ rejection, have familiarity with perioperative complications, and have the ability to manage the long-term effects of chronic immunosuppression. This skill set at the intersection of multiple disciplines necessitates additional training in Transplant Nephrology. Currently, there are more than 250,000 patients with a functioning kidney allograft and over 100,000 waitlisted patients awaiting kidney transplant, with a burgeoning number added to the kidney transplant wait list every year. In 2022, more than 40,000 patients were added to the kidney wait list and more than 25,000 received a kidney transplant. The Advancing American Kidney Health Initiative, passed in 2019, is aiming to double the number of kidney transplants by 2030 creating a need for additional transplant nephrologists to help care for them. Over the past decade, there has been a decline in the Nephrology-as well Transplant Nephrology-workforce due to a multitude of reasons. The American Society of Transplantation Kidney Pancreas Community of Practice created a workgroup to discuss the Transplant Nephrology workforce shortage. In this article, we discuss the scope of the problem and how the Accreditation Council for Graduate Medical Education recognition of Transplant Nephrology Fellowship could at least partly mitigate the Transplant Nephrology work force crisis.
- Singh, N., Anand, P., Gupta, G., Sawinski, D., Fix, O., Adey, D., Akalin, E., Zayas, C., Dadhania, D., Doshi, M., Cibrik, D., Gupta, M., Parsons, R., Leca, N., Santos, R., Concepcion, B., Nishio Lucar, A., Ong, S., Sridhar, V., , Parajuli, S., et al. (2024). Should Transplant Nephrology Pursue Recognition from the Accreditation Council for Graduate Medical Education (ACGME)?. Clinical Journal of the American Society of Nephrology, 19(8). doi:10.2215/CJN.0000000000000441More infoKidney transplant is not only the best treatment for patients with advanced kidney disease but it also reduces health care expenditure. The management of transplant patients is complex as they require special care by transplant nephrologists who have expertise in assessing transplant candidates, understand immunology and organ rejection, have familiarity with perioperative complications, and have the ability to manage the long-term effects of chronic immunosuppression. This skill set at the intersection of multiple disciplines necessitates additional training in Transplant Nephrology. Currently, there are more than 250,000 patients with a functioning kidney allograft and over 100,000 waitlisted patients awaiting kidney transplant, with a burgeoning number added to the kidney transplant wait list every year. In 2022, more than 40,000 patients were added to the kidney wait list and more than 25,000 received a kidney transplant. The Advancing American Kidney Health Initiative, passed in 2019, is aiming to double the number of kidney transplants by 2030 creating a need for additional transplant nephrologists to help care for them. Over the past decade, there has been a decline in the Nephrology - as well Transplant Nephrology - workforce due to a multitude of reasons. The American Society of Transplantation Kidney Pancreas Community of Practice created a workgroup to discuss the Transplant Nephrology workforce shortage. In this article, we discuss the scope of the problem and how the Accreditation Council for Graduate Medical Education recognition of Transplant Nephrology Fellowship could at least partly mitigate the Transplant Nephrology work force crisis.
- Ulvi Saygi Ayvaci, M., Jacobi, V. S., Ryu, Y., Gundreddy, S. P., & Tanriover, B. (2024). Clinically Guided Adaptive Machine Learning Update Strategies for Predicting Severe COVID-19 Outcomes. The American journal of medicine.More infoMachine learning algorithms are essential for predicting severe outcomes during public health crises like COVID-19. However, the dynamic nature of diseases requires continual evaluation and updating of these algorithms. This study aims to compare three update strategies for predicting severe COVID-19 outcomes postdiagnosis: "naive" (a single initial model), "frequent" (periodic retraining), and "context-driven" (retraining informed by clinical insights). The goal is to determine the most effective timing and approach for adapting algorithms to evolving disease dynamics and emerging data.
- Ulvi Saygi Ayvaci, M., Jacobi, V., Ryu, Y., Gundreddy, S., & Tanriover, B. (2024). Clinically Guided Adaptive Machine Learning Update Strategies for Predicting Severe COVID-19 Outcomes. American Journal of Medicine. doi:10.1016/j.amjmed.2024.10.011More infoBackground: Machine learning algorithms are essential for predicting severe outcomes during public health crises like COVID-19. However, the dynamic nature of diseases requires continual evaluation and updating of these algorithms. This study aims to compare three update strategies for predicting severe COVID-19 outcomes postdiagnosis: “naive” (a single initial model), “frequent” (periodic retraining), and “context-driven” (retraining informed by clinical insights). The goal is to determine the most effective timing and approach for adapting algorithms to evolving disease dynamics and emerging data. Methods: A dataset of 1.11 million COVID-19 patients from diverse U.S. regions was used to develop and validate an XGBoost algorithm for predicting severe outcomes upon diagnosis. Data included patient demographics, vital signs, comorbidities, and immunity-related factors (prior infection and vaccination status) from January 2007 to November 2021. The study analyzed the performance of the three update strategies from March 2020 to November 2021. Results: Predictive features changed over the pandemic, with comorbidities and vitals being significant initially, and geography, demographics, and immunity-related variables gaining importance later. The “naive” strategy had an average area under the curve (AUC) of 0.77, the “frequent” strategy maintained stability with an average AUC of 0.81, and the “context-driven” strategy averaged an AUC of 0.80, outperforming the “naive” strategy and aligning closely with the “frequent” strategy. Conclusions: A context-driven approach, guided by clinical insights, can enhance predictive performance and offer cost-effective solutions for dynamic public health challenges. These findings have significant implications for efficiently managing healthcare resources during evolving disease outbreaks.
- Al-Obaidi, M. M., Gungor, A. B., Murugapandian, S., Thajudeen, B., Mansour, I., Wong, R. C., Tanriover, B., & Zangeneh, T. T. (2023). The Impact of Nirmatrelvir-Ritonavir in Reducing Hospitalizations Among High-Risk Patients With SARS-CoV-2 During the Omicron Predominant Era. The American journal of medicine, 136(6), 577-584.More infoThe coronavirus disease 2019 (COVID-19) pandemic has caused significant morbidity and mortality in high-risk populations. Several therapeutics have been developed to reduce the risk of complications related to COVID-19, hospitalizations, and death. In several studies, nirmatrelvir-ritonavir (NR) was reported to reduce the risk of hospitalizations and death. We aimed to evaluate the efficacy of NR in preventing hospitalizations and death during the Omicron predominant period.
- Mansour, I., Murugapandian, S., Tanriover, B., & Thajudeen, B. (2023). Contemporary Monoclonal Antibody Utilization in Glomerular Diseases. Mayo Clinic proceedings. Innovations, quality & outcomes, 7(4), 276-290.More infoTherapeutic monoclonal antibodies (MAbs) have been one of the fastest growing drug classes in the past 2 decades and are indicated in the treatment of cancer, autoimmune disorders, solid organ transplantation, and glomerular diseases. The Food and Drug Administration has approved 100 MAbs between 1986 and 2021, and MAbs account for 20% of Food and Drug Administration's new drug approval every year. MAbs are preferred over traditional immunosuppressive agents because of their high specificity, reduced number of drug-drug interactions, and low toxicity, which make them a prime example of personalized medicine. In this review article, we provide an overview of the taxonomy, pharmacology, and therapeutic applications of MAbs in glomerular diseases. We searched the literature through PubMed using the following search terms: , and limited our search to years 2018-2023. We selected peer-reviewed journal articles with an evidence-based approach, prioritizing randomized control trials in specific glomerular diseases, if available. Advances in the MAb field have resulted in a significant paradigm shift in targeted treatment of immune-mediated glomerular diseases, and multiple randomized control trials are currently being conducted. Increased recognition is critical to expand their use in experimental research and personalized medicine.
- Sridhara, S., Gungor, A. B., Erol, H. K., Al-Obaidi, M., Zangeneh, T. T., Bedrick, E. J., Ariyamuthu, V. K., Shetty, A., Qannus, A. A., Mendoza, K., Murugapandian, S., Gupta, G., & Tanriover, B. (2023). Lack of effectiveness of Bebtelovimab monoclonal antibody among high-risk patients with SARS-Cov-2 Omicron during BA.2, BA.2.12.1 and BA.5 subvariants dominated era. PloS one, 18(4), e0279326.More infoSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariants are expected to be resistant to Bebtelovimab (BEB) monoclonal antibody (MAb) and the real-world experience regarding its effectiveness is scarce. This retrospective cohort study reports a data analysis in Banner Healthcare System (a large not-for-profit organization) between 4/5/2022 and 8/1/2022 and included 19,778 Coronavirus disease-19 (COVID-19) positive (by PCR or direct antigen testing) patients who were selected from Cerner-Electronic Health Record after the exclusions criteria were met. The study index date for cohort was determined as the date of BEB MAb administration or the date of the first positive COVID-19 testing. The cohort consist of COVID-19 infected patients who received BEB MAb (N = 1,091) compared to propensity score (PS) matched control (N = 1,091). The primary composite outcome was the incidence of 30-day all-cause hospitalization and/or mortality. All statistical analyses were conducted on the paired (matched) dataset. For the primary composite outcome, the event counts and percentages were reported. Ninety-five percent Clopper-Pearson confidence intervals for percentages were computed. The study cohorts were 1:1 propensity matched without replacement across 26 covariates using an optimal matching algorithm that minimizes the sum of absolute pairwise distance across the matched sample after fitting and using logistic regression as the distance function. The pairs were matched exactly on patient vaccination status, BMI group, age group and diabetes status. Compared to the PS matched control group (2.6%; 95% confidence interval [CI]: 1.7%, 3.7%), BEB MAb use (2.2%; 95% CI: 1.4%, 3.3%) did not significantly reduce the incidence of the primary outcome (p = 0.67). In the subgroup analysis, we observed similar no-difference trends regarding the primary outcomes for the propensity rematched BEB MAb treated and untreated groups, stratified by patient vaccination status, age (
- Tanriover, B., Stewart, D., Kamal, L., Saeed, M., Cooper, M., Foutz, J., McGehee, H., & Gupta, G. (2023). The Independent Effects of Kidney Length and Vascular Plaque on Ten-Year Outcomes of Extended Criteria Donor Kidney Transplants. Transplant international : official journal of the European Society for Organ Transplantation, 36, 11373.More infoThe independent effects of deceased donor kidney length and vascular plaque on long-term graft survival are not established. Utilizing DonorNet attachments from 4,480 expanded criteria donors (ECD) recovered between 2008 and 2012 in the United States with at least one kidney biopsied and transplanted, we analyzed the relationship between kidney length and vascular plaques and 10-year hazard of all-cause graft failure (ACGF) using causal inference methods in a Cox regression framework. The composite plaque score (range 0-4) and the presence of any plaque (yes, no) was also analyzed. Kidney length was modeled both categorically (12 cm) as well as numerically, using a restricted cubic spline to capture nonlinearity. Effects of a novel composite plaque score 4 vs. 0 (HR 1.08; 95% CI: 0.96, 1.23) and the presence of any vascular plaque (HR 1.08; 95% CI: 0.98, 1.20) were attenuated after adjustment. Likewise, we identified a potential nonlinear relationship between kidney length and the 10-year hazard of ACGF, however the strength of the relationship was attenuated after adjusting for other donor factors. The independent effects of vascular plaque and kidney length on long-term ECD graft survival were found to be minimal and should not play a significant role in utilization.
- Yamauchi, J., Azhar, A., Hall, I. E., Bhalla, A., Potluri, V. S., Tanriover, B., Gupta, G., Imlay, H., Truax, C., Balaraman, V., Raghavan, D., Zimmerman, M., Campsen, J., Rofaiel, G., Baker, T., & Molnar, M. Z. (2023). Comparison of Short-Term Outcomes in Kidney Transplant Recipients from SARS-CoV-2-Infected versus Noninfected Deceased Donors. Clinical journal of the American Society of Nephrology : CJASN, 18(11), 1466-1475.More infoAcceptable post-transplant outcomes were reported in kidney transplant recipients from donors with coronavirus disease 2019 (COVID-19); however, there are no comparative studies with well-matched controls.
- Al-Obaidi, M. M., Gungor, A. B., Kurtin, S. E., Mathias, A. E., Tanriover, B., & Zangeneh, T. T. (2023). The Prevention of COVID-19 in High-Risk Patients Using Tixagevimab-Cilgavimab (Evusheld): Real-World Experience at a Large Academic Center. The American journal of medicine, 136(1), 96-99.More infoCoronavirus disease 2019 (COVID-19) is associated with increased morbidity and mortality among immunocompromised patients. Tixagevimab-cilgavimab (Tix-Cil) is a combination of 2 monoclonal antibodies approved for the prevention of COVID-19 complications in this high-risk group.
- Al-Obaidi, M. M., Gungor, A. B., Nematollahi, S., Zangeneh, T. T., Bedrick, E. J., Johnson, K. M., Low-Adegbija, N. E., Alam, R., Rangan, P., William Heise, C., Ariyamuthu, V. K., Shetty, A., Qannus, A. A., Murugapandian, S., Ayvaci, M. M., Anand, P. M., & Tanriover, B. (2022). Effectiveness of Casirivimab-Imdevimab Monoclonal Antibody Treatment Among High-Risk Patients With Severe Acute Respiratory Syndrome Coronavirus 2 B.1.617.2 (Delta Variant) Infection. Open forum infectious diseases, 9(7), ofac186.More infoReal-world data on the effectiveness of neutralizing casirivimab-imdevimab monoclonal antibody (Cas-Imd mAb) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among high-risk patients may inform the response to future SARS-CoV-2 variants.
- Azhar, A., Kleiboeker, S., Khorsandi, S., Duncan Kilpatrick, M., Khan, A., Gungor, A., Molnar, M. Z., Morales, M., Levy, M., Kamal, L., Moinuddin, I., Kumar, D., Tanriover, B., & Gupta, G. (2022). Detection of Transmissible Severe Acute Respiratory Syndrome Coronavirus-2 From Deceased Kidney Donors: Implications for Kidney Transplant Recipients. Transplantation, 107(2), e65-e67. doi:10.1097/tp.0000000000004422
- Azhar, A., Kleiboeker, S., Khorsandi, S., Duncan Kilpatrick, M., Khan, A., Gungor, A., Molnar, M. Z., Morales, M., Levy, M., Kamal, L., Moinuddin, I., Kumar, D., Tanriover, B., & Gupta, G. (2023). Detection of Transmissible Severe Acute Respiratory Syndrome Coronavirus-2 From Deceased Kidney Donors: Implications for Kidney Transplant Recipients. Transplantation, 107(2), e65-e67.
- Batra, R. K., Ariyamuthu, V. K., MacConmara, M. P., Gupta, G., Gungor, A. B., & Tanriover, B. (2022). Outcomes of simultaneous liver-kidney transplant using kidneys of deceased donors with acute kidney injury. Liver transplantation : official publication of the American Association for the Study of Liver Diseases and the International Liver Transplantation Society.More infoTo our knowledge, outcomes from simultaneous liver-kidney transplant (SLKT) when using kidneys from donors with acute kidney injury (AKI) have not been studied. We studied 5344 SLKTs between May 1, 2007, and December 31, 2019, by using Organ Procurement and Transplantation Network registry data supplemented with United Network for Organ Sharing-DonorNet data. Designating a donor as having AKI required by definition that the following criteria were met: (1) the donor's condition aligned with the Kidney Disease: Improving Global Outcomes (KDIGO) international consensus guidelines, and the terminal serum creatinine (Scr) level was greater than or equal to 1.5 times the minimum Scr level for deceased donors before organ recovery, regardless of urine output, and (2) the terminal Scr level was 1.5 mg/dl or higher (a clinically meaningful and intuitive Scr threshold for defining AKI for transplant providers). The primary outcomes were liver transplant all-cause graft failure (ACGF) (defined as graft failures and deaths) and kidney transplant death-censored graft failure (DCGF) at 1 year after transplant. The secondary outcome was the use of mate kidneys. In the study cohort, 4482 donors had no AKI, whereas 862 had AKI (KDIGO AKI stages: stage 1, n = 521; stage 2, n = 202; and stage 3, n = 138). The donors with AKI were young (median age, 35 years), had good organ quality (median kidney donor profile index, 40%), and had a short cold ischemia time (CIT) (median CIT, 10.6 hours). In the group with AKI and the group with no AKI, respectively, liver ACGF at 1 year (11.1% versus 12.9% [p = 0.13]; hazard ratio [HR], 1.20; 95% confidence interval [CI], 0.97-1.49) and kidney DCGF at 1 year (4.6% versus 5.7% [p = 0.18]; HR, 1.27; 95% CI, 0.95-1.70) did not differ in the full multivariable Cox proportional hazard models. The mate kidneys were allocated to deceased donor kidney transplants (n = 3979, 74.5%) and other multiorgan transplants (n = 995, 18.6%). The discard rate in the group with AKI was 10.9% (n = 370), approximately twice as high as that in the group with no AKI (6.2%: p < 0.001). Selected kidneys from deceased donors with AKI can be considered for SLKT.
- Gupta, G., & Tanriover, B. (2023). Donor-derived Cell-free DNA Measurement in Kidney Transplant Patients Without Allograft Dysfunction: More Evidence and More Questions. Transplantation, 107(1), 25-26.
- Gupta, G., Azhar, A., Gungor, A., Molnar, M. Z., Morales, M. K., & Tanriover, B. (2022). Early Data on Utilization and Discard of Organs From COVID-19-infected Donors: A US National Registry Analysis. Transplantation, 106(5), e266-e268.
- Kelly, B., Stratton, D., Mansour, I., Tanriover, B., Culpepper, K., & Curiel-Lewandrowski, C. (2022). Navigating the initial diagnosis and management of adult IgA vasculitis: A review. JAAD International, 8. doi:10.1016/j.jdin.2022.05.004More infoBackground: IgA vasculitis in adults has not been thoroughly studied. This has left a practice gap related to the management and follow-up of a population that is at an increased risk of comorbidities and potentially poor outcomes. For this reason, it is important to synthesize evidence from the current literature because this can help direct the movement for more robust studies to clarify best practice recommendations. Objective: We sought to create a narrative review for the practicing dermatologist when diagnosing and leading the care of IgA vasculitis in adult patients. Methods: A broad literature search was performed with a focus on articles that were published after the introduction of the most updated European Alliance of Associations for Rheumatology/Pediatric Rheumatology International Trials Organization/Pediatric Rheumatology European Society criteria. Results: The characteristics and management guidelines for IgA vasculitis in adults have been refined, although more rigorous studies are needed to develop best practice recommendations. Limitations: Because of the lack of sufficient randomized controlled trials on IgA vasculitis in adults, this narrative review is composed of mostly observational, descriptive studies. Conclusion: Adults with IgA vasculitis are at an increased risk of complicated disease course, necessitating formal diagnostic assessment and clear-cut follow-up recommendations to manage and prevent poor health outcomes related to various comorbidities.
- Mete, M., Ayvaci, M. U., Ariyamuthu, V. K., Amin, A., Peltz, M., Thibodeau, J. T., Grodin, J. L., Mammen, P. P., Garg, S., Araj, F., Morlend, R., Drazner, M. H., AbdulRahim, N., Kim, Y., Salam, Y., Gungor, A. B., Delibasi, B., Kotla, S. K., MacConmara, M. P., , Mohan Anand, P., et al. (2022). Predicting Post-Heart Transplant Composite Renal Outcome Risk in Adults: A Machine Learning Decision Tool. Kidney international reports, 7(6), 1410-1415.
- Sandıkçı, B., Tanrıöver, B., & Tunç, S. (2022). A Simple Incentive Mechanism to Alleviate the Burden of Organ Wastage in Transplantation. Management Science, 68(8). doi:10.1287/mnsc.2021.4203More infoDespite efforts to increase the supply of donated organs for transplantation, organ shortages persist. We study the problem of organ wastage in a queueing-theoretic framework. We establish that self-interested individuals set their utilization levels more conservatively in equilibrium than the socially efficient level. To reduce the resulting gap, we offer an incentive mechanism that recompenses candidates returning to the waitlist for retransplantation, who have accepted a predefined set of organs, for giving up their position in the waitlist and show that it increases the equilibrium utilization of organs while also improving social welfare. Furthermore, the degree of improvement increases monotonically with the level of this nonmonetary compensation provided by the mechanism. In practice, this mechanism can be implemented by preserving some fraction of the waiting time previously accumulated by returning candidates. A detailed numerical study for the U.S. renal transplant system suggests that such an incentive helps significantly reduce the kidney discard rate (baseline: 17.4%). Depending on the strength of the population’s response to the mechanism, the discard rate can be as low as 6.2% (strong response), 12.4% (moderate response), or 15.1% (weak response), which translates to 1,630, 724, or 338 more transplants per year, respectively. Although the average quality of transplanted kidneys deteriorates slightly, the resulting graft survival one-year posttransplant remains stable around 94.8% versus 95.0% for the baseline. We find that the optimal Kidney Donor Profile Index score cutoff, defining the set of incentivized kidneys, is around 85%, which coincides with the generally accepted definition of marginal kidneys in the medical community.
- Shetty, A., Ariyamuthu, V. K., Gungor, A. B., & Tanriover, B. (2022). Utilization of hepatitis C virus-positive donors in kidney transplantation. Current Opinion in Organ Transplantation, 28(1), 22-28. doi:10.1097/mot.0000000000001031
- Singh, G., DeWalle, J., Tanriover, B., Singh, N., Chang, A. R., & Anand, P. M. (2022). Effect of age and rural residency on perceptions about SARS-CoV-2 pandemic and vaccination in kidney transplant recipients. Transplant infectious disease : an official journal of the Transplantation Society, 24(6), e13943.More infoTransplant patients have poor outcomes in coronavirus-disease 2019 (COVID-19). The pandemic's effects on rural patients' overall care experience, attitudes to telemedicine, and vaccination are poorly understood.
- Singh, G., Gohh, R., Clark, D., Kalra, K., Das, M., Bradauskaite, G., Bleyer, A. J., Tanriover, B., Chang, A. R., & Anand, P. M. (2022). Vignette-Based Reflections to Inform Genetic Testing Policies in Living Kidney Donors. Genes, 13(4).More infoFamily history of kidney disease increases risk of end-stage kidney disease (ESKD) in donors. Pre-donation genetic testing is recommended in evaluation guidelines and regulatory policy. Collaborating across several institutions, we describe cases to illustrate the utility as well as practical issues in incorporating genetic testing in transplant protocols. Case 1 is from 2009, before pervasive genetic testing. A healthy 27-year-old Caucasian male had an uneventful donor evaluation for his mother, who had early onset ESKD of unclear cause. He participated in paired-exchange kidney donation, but developed progressive kidney disease and gout over the next 10 years. A uromodulin gene mutation (NM_003361.3():c.377 G>A p.C126Y) was detected and kidney biopsy showed tubulointerstitial kidney disease. The patient subsequently required kidney transplantation himself. Case 2 was a 36-year-old African American female who had an uneventful kidney donor evaluation. She underwent gene panel-based testing to rule out ApolipoproteinL1 risk variants, for which was negative. Incidentally, a sickle-cell trait (NM_000518.5():c.20A>T p.Glu7Val) was noted, and she was declined for kidney donation. This led to significant patient anguish. Case 3 was a 26-year-old Caucasian female who underwent panel-based testing because the potential recipient, her cousin, carried a variant of uncertain significance in the hepatocyte nuclear factor-1-β () gene. While the potential donor did not harbor this variant, she was found to have a likely pathogenic variant in complement factor I (NM_000204.4():c.1311dup:p.Asp438Argfs*8), precluding kidney donation. Our cases emphasize that while genetic testing can be invaluable in donor evaluation, transplant centers should utilize detailed informed consent, develop care pathways for secondary genetic findings, and share experience to develop best practices around genetic testing in donors.
- Stewart, D., Tanriover, B., & Gupta, G. (2022). Oversimplification and Misplaced Blame Will Not Solve the Complex Kidney Underutilization Problem. Kidney360, 3(12), 2143-2147.
- Tanriover, B., Anand, P. M., Ayvaci, M., Murugapandian, S., Qannus, A. A., Shetty, A., ARIYAMUTHU, V. K., Heise, C. W., Rangan, P., Alam, R., Nicole, A., Johnson, K., Bedrick, E. J., Zangeneh, T. T., Nematollahi, S., Gungor, A. b., & Al-Obaidi, M. (2022).
Effectiveness of Casirivimab-Imdevimab Monoclonal Antibody Treatment Among High-Risk Patients With Severe Acute Respiratory Syndrome Coronavirus 2 B.1.617.2 (Delta Variant) Infection
. Open forum infectious diseases. - Özer, Y., Kaplan, S., Sandikçi, B., Gupta, G., & Tanriover, B. (2022). Increased Rates of Kidney Discard in the Era of COVID-19 and Recent KAS Policy Implementation. Transplantation, 106(11), e503-e506.
- MacConmara, M., Wang, B., Patel, M. S., Hwang, C. S., DeGregorio, L., Shah, J., Hanish, S. I., Desai, D., Lynch, R., Tanriover, B., Zeh, H., & Vagefi, P. A. (2021). Liver Transplantation in the Time of a Pandemic: A Widening of the Racial and Socioeconomic Health Care Gap During COVID-19. Annals of surgery, 274(3), 427-433.More infoDuring the initial wave of the COVID-19 pandemic, organ transplantation was classified a CMS Tier 3b procedure which should not be postponed. The differential impact of the pandemic on access to liver transplantation was assessed.
- Tanriover, B., Lingvay, I., Ahmed, F., Sandikci, B., Mohan, S., Cremers, S., Karmally, W., Mohan, P., Newhouse, J., Ragunathan, S., AbdulRahim, N., Ariyamuthu, V. K., Ratner, L. E., & Cohen, D. J. (2021). Insulin Sensitivity After Living Donor Nephrectomy. Transplantation proceedings, 53(6), 1858-1864.More infoThe kidney is essential for glucose and insulin metabolism. Living kidney donors (LKDs) experience a reduction in glomerular filtration rate of 25 to 30 mL/min after donor nephrectomy. Little is known about the effect of glomerular filtration rate decline on insulin sensitivity in LKDs.
- Ariyamuthu, V. K., Sandikci, B., AbdulRahim, N., Hwang, C., MacConmara, M. P., Parasuraman, R., Atis, A., & Tanriover, B. (2020). Trends in utilization of deceased donor kidneys based on hepatitis C virus status and impact of public health service labeling on discard. Transplant infectious disease : an official journal of the Transplantation Society, 22(1), e13204.More infoKidneys from deceased donors infected with hepatitis C virus (HCV) are underutilized. Most HCV virus-infected donors are designated as Public Health Service increased donors (PHS-IR). Impact of PHS and HCV designations on discard is not well studied.
- Giacoma, T., Ayvaci, M. U., Gaston, R. S., Mejia, A., & Tanriover, B. (2020). Transplant physician and surgeon compensation: A sample framework accounting for nonbillable and value-based work. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons, 20(3), 641-652.More infoWork relative value unit (wRVU)-based fee schedules are predominantly used by both the Centers for Medicare & Medicaid Services (CMS) and private payers to determine the payments for physicians' clinical productivity. However, under the Affordable Care Act, CMS is transitioning into a value-based payment structure that rewards patient-oriented outcomes and cost savings. Moreover, in the context of solid organ transplantation, physicians and surgeons conduct many activities that are neither billable nor accounted for in the wRVU models. New compensation models for transplant professionals must (1) justify payments for nonbillable work related to transplant activity/procedures; (2) capture the entire academic, clinical, and relationship-building work effort as part of RVU determination; and (3) move toward a value-based compensation scheme that aligns the incentives for physicians, surgeons, transplant center, payers, and patients. In this review, we provide an example of redesigning RVUs to address these challenges in compensating transplant physicians and surgeons. We define a customized RVU (cRVU) for activities that typically do not generate wRVUs and create an outcome value unit (OVU) measure that incorporates outcomes and cost savings into RVUs to include value-based compensation.
- Woll, F., Mohanka, M., Bollineni, S., Joerns, J., Kaza, V., Torres, F., Tanriover, B., & Banga, A. (2020). Characteristics and Outcomes of Lung Transplant Candidates With Preexisting Renal Dysfunction. Transplantation proceedings, 52(1), 302-308.More infoThe proportion of lung transplant candidates with comorbid renal dysfunction (RD) may rise as sicker patients are being considered for lung transplant (LT). There is lack of data regarding the characteristics and outcome of patients with RD and the role of simultaneous lung-kidney transplant (SLuKi) among these patients.
- AbdulRahim, N., & Tanriover, B. (2019). Reply. Liver transplantation : official publication of the American Association for the Study of Liver Diseases and the International Liver Transplantation Society, 25(4), 669-670.
- Amin, A. A., Araj, F. G., Ariyamuthu, V. K., Drazner, M. H., Ayvaci, M. U., Mammen, P. P., Mete, M., Urey, M. A., & Tanriover, B. (2019). Impact of induction immunosuppression on patient survival in heart transplant recipients treated with tacrolimus and mycophenolic acid in the current allocation era. Clinical transplantation, 33(8), e13651.More infoThe practice of induction therapy with either rabbit anti-thymocyte globulin (r-ATG) or interleukin-2 receptor antagonists (IL-2RA) is common among heart transplant recipients. However, its benefits in the setting of contemporary maintenance immunosuppression with tacrolimus/mycophenolic acid (TAC/MPA) are unknown.
- Hassler, J., Tanriover, B., Ariyamutu, V., Burguete, D., Hendricks, A. R., & Torrealba, J. R. (2019). 2013 Banff Criteria for Acute Antibody-Mediated Rejection Are Superior to 2007 Banff Criteria in the Diagnosis and Assessment of Renal Allograft Outcomes. Transplantation proceedings, 51(6), 1791-1795.More infoThe 2013 Banff meeting updated the requirements for the diagnosis of acute/active antibody-mediated rejection (AAMR) in kidney allografts. There has been speculation that the changes lower the threshold for diagnosing AAMR, and may lead to possible unnecessary and expensive treatment.
- La Hoz, R. M., Sandıkçı, B., Ariyamuthu, V. K., & Tanriover, B. (2019). Short-term outcomes of deceased donor renal transplants of HCV uninfected recipients from HCV seropositive nonviremic donors and viremic donors in the era of direct-acting antivirals. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons, 19(11), 3058-3070.More infoThe United States opioid use epidemic over the past decade has coincided with an increase in hepatitis C virus (HCV) positive donors. Using propensity score matching, and the Organ Procurement Transplant Network data files from January 2015 to June 2019, we analyzed the short-term outcomes of adult deceased donor kidney transplants of HCV uninfected recipients with two distinct groups of HCV positive donors (HCV seropositive, nonviremic n = 352 and viremic n = 196) compared to those performed using HCV uninfected donors (n = 36 934). Compared to the reference group, the transplants performed using HCV seropositive, nonviremic and viremic donors experienced a lower proportion of delayed graft function (35.2 vs 18.9%; P < .001 [HCV seropositive, nonviremic donors] and 36.2 vs 16.8% ; P < .001[HCV viremic donors]). The recipients of HCV viremic donors had better allograft function at 6 months posttransplant (eGFR [54.1 vs 68.3 mL/min/1.73 m2; P = .004]. Furthermore, there was no statistical difference in the overall graft failure risk at 12 months posttransplant by propensity score matched multivariable Cox proportional analysis (HR = 0.60, 95% CI 0.23 to 1.29 [HCV seropositive, nonviremic donors] and HR = 0.85, 95% CI 0.25 to 2.96 [HCV viremic donors]). Further studies are required to determine the long-term outcomes of these transplants and address unanswered questions regarding the use of HCV viremic donors.
Reviews
- Kelly, B. G., Stratton, D. B., Mansour, I., Tanriover, B., Culpepper, K. S., & Curiel-Lewandrowski, C. (2022. Navigating the initial diagnosis and management of adult IgA vasculitis: A review(pp 71-78).More infoIgA vasculitis in adults has not been thoroughly studied. This has left a practice gap related to the management and follow-up of a population that is at an increased risk of comorbidities and potentially poor outcomes. For this reason, it is important to synthesize evidence from the current literature because this can help direct the movement for more robust studies to clarify best practice recommendations.
- Shetty, A., Ariyamuthu, V. K., Gungor, A. B., & Tanriover, B. (2023. Utilization of hepatitis C virus-positive donors in kidney transplantation(pp 22-28).More infoDirect-acting antivirals (DAA) have transformed kidney transplantation by increasing the donor pool from hepatitis C virus (HCV)-infected donors and allowing HCV nucleic acid amplification testing (NAT) donor-positive/recipient-negative (D+/R-) transplantation over the last 7 years. Willingness to accept kidneys from HCV-infected donors and timing/duration of DAA therapy have been evolving.