RESUMO
In the United States, potential transplant candidates with insulin-dependent diabetes mellitus are inconsistently offered pancreas transplantation (PTx), contributing to a dramatic decline in pancreas allograft utilization over the past 2 decades. The American Society of Transplantation organized a workshop to identify barriers inhibiting PTx and to develop strategies for a national comeback. The 2-day workshop focused on 4 main topics: (1) referral/candidate selection, (2) organ recovery/utilization, (3) program performance/patient outcomes, and (4) enhanced education/research. Topics were explored through expert presentations, patient testimonials, breakout sessions, and strategic planning, including the identification of tasks for immediate focus. Additionally, a modified-Delphi survey was conducted among workshop members to develop and rate the importance of barriers, and the impact and feasibility of workgroup-identified improvement strategies. The panelists identified 16 barriers to progress and 44 strategies for consideration. The steps for a national comeback in PTx involve greater emphasis on efficient referral and candidate selection, better donor pancreas utilization practices, eliminating financial barriers to procurement and transplant, improving collaboration between transplant and diabetes societies and professionals, and increasing focus on PTx training, education, and research. Partnership between national societies, patient advocacy groups, and professionals will be essential to realizing this critical agenda.
Assuntos
Transplante de Pâncreas , Humanos , Estados Unidos , Técnica Delphi , Obtenção de Tecidos e Órgãos , Doadores de Tecidos/provisão & distribuição , Diabetes Mellitus Tipo 1/cirurgiaRESUMO
The Banff pancreas working schema for diagnosis and grading of rejection is widely used for treatment guidance and risk stratification in centers that perform pancreas allograft biopsies. Since the last update, various studies have provided additional insight regarding the application of the schema and enhanced our understanding of additional clinicopathologic entities. This update aims to clarify terminology and lesion description for T cell-mediated and antibody-mediated allograft rejections, in both active and chronic forms. In addition, morphologic and immunohistochemical tools are described to help distinguish rejection from nonrejection pathologies. For the first time, a clinicopathologic approach to islet pathology in the early and late posttransplant periods is discussed. This update also includes a discussion and recommendations on the utilization of endoscopic duodenal donor cuff biopsies as surrogates for pancreas biopsies in various clinical settings. Finally, an analysis and recommendations on the use of donor-derived cell-free DNA for monitoring pancreas graft recipients are provided. This multidisciplinary effort assesses the current role of pancreas allograft biopsies and offers practical guidelines that can be helpful to pancreas transplant practitioners as well as experienced pathologists and pathologists in training.
Assuntos
Transplante de Pâncreas , Transplante Homólogo , Biópsia , Isoanticorpos , Linfócitos TRESUMO
Delayed graft function (DGF) is a common complication after kidney transplant. Despite extensive literature on the topic, the extant definition of DGF has not been conducive to advancing the scientific understanding of the influences and mechanisms contributing to its onset, duration, resolution, or long-term prognostic implications. In 2022, the National Kidney Foundation sponsored a multidisciplinary scientific workshop to comprehensively review the current state of knowledge about the diagnosis, therapy, and management of DGF and conducted a survey of relevant stakeholders on topics of clinical and regulatory interest. In this Special Report, we propose and defend a novel taxonomy for the clinical and research definitions of DGF, address key regulatory and clinical practice issues surrounding DGF, review the current state of therapies to reduce and/or attenuate DGF, offer considerations for clinical practice related to the outpatient management of DGF, and outline a prospective research and policy agenda.
Assuntos
Função Retardada do Enxerto , Transplante de Rim , Humanos , Função Retardada do Enxerto/terapia , Estudos Prospectivos , Rim , Transplante de Rim/efeitos adversos , Prognóstico , Fatores de Risco , Sobrevivência de Enxerto , Rejeição de Enxerto/etiologiaRESUMO
Kidney transplantation is the most successful kidney replacement therapy available, resulting in improved recipient survival and societal cost savings. Yet, nearly 70 years after the first successful kidney transplant, there are still numerous barriers and untapped opportunities that constrain the access to transplant. The literature describing these barriers is extensive, but the practices and processes to solve them are less clear. Solutions must be multidisciplinary and be the product of strong partnerships among patients, their networks, health care providers, and transplant programs. Transparency in the referral, evaluation, and listing process as well as organ selection are paramount to build such partnerships. Providing early culturally congruent and patient-centered education as well as maximizing the use of local resources to facilitate the transplant work up should be prioritized. Every opportunity to facilitate pre-emptive kidney transplantation and living donation must be taken. Promoting the use of telemedicine and kidney paired donation as standards of care can positively impact the work up completion and maximize the chances of a living donor kidney transplant.
Assuntos
Acessibilidade aos Serviços de Saúde , Falência Renal Crônica , Transplante de Rim , Obtenção de Tecidos e Órgãos , Humanos , Obtenção de Tecidos e Órgãos/métodos , Falência Renal Crônica/cirurgia , Doadores Vivos/provisão & distribuição , Listas de EsperaRESUMO
Well-selected patients with kidney disease and diabetes mellitus who undergo simultaneous kidney-pancreas transplantation often experience dramatic improvements in quality of life and long-term survival compared to those who remain on medical therapy. Over the past several years the importance of frailty in the pancreas transplant candidate and recipient populations has grown. More patients with advanced age have entered the waitlist, and complications from prolonged diabetes, even in younger patients, have created increased evidence of risk for frailty. Given these concerns, and the broad challenges facing pancreas transplantation volumes overall, we generated this review to help establish the impact and implications. We summarize the interplay of immunological factors, aging, environmental factors, diabetes mellitus, and chronic kidney disease that put these patients at risk for frailty. We discuss its measurement and recommend a combination of two instruments (both well-validated and one entirely objective). We describe the outcomes for patients before and after pancreas transplantation who may have frailty, and what interventions can be taken to mitigate its effects. Broader investigation into frailty in the pancreas transplant population is needed to better understand how to select patients for pancreas transplantation and to how manage its consequences thereafter.
Assuntos
Diabetes Mellitus Tipo 1 , Fragilidade , Transplante de Rim , Transplante de Pâncreas , Humanos , Transplante de Pâncreas/efeitos adversos , Diabetes Mellitus Tipo 1/complicações , Qualidade de Vida , Fragilidade/complicações , Transplante de Rim/efeitos adversos , Sobrevivência de EnxertoRESUMO
The management of failing kidney allograft and transition of care to general nephrologists (GN) remain a complex process. The Kidney Pancreas Community of Practice (KPCOP) Failing Allograft Workgroup designed and distributed a survey to GN between May and September 2021. Participants were invited via mail and email invitations. There were 103 respondents with primarily adult nephrology practices, of whom 41% had an academic affiliation. More than 60% reported listing for a second kidney as the most important concern in caring for patients with a failing allograft, followed by immunosuppression management (46%) and risk of mortality (38%), while resistant anemia was considered less of a concern. For the initial approach to immunosuppression reduction, 60% stop antimetabolites first, and 26% defer to the transplant nephrologist. Communicating with transplant centers about immunosuppression cessation was reported to occur always by 60%, and sometimes by 29%, while 12% reported making the decision independently. Nephrologists with academic appointments communicate with transplant providers more than private nephrologists (74% vs. 49%, p = 0.015). There are heterogeneous approaches to the care of patients with a failing allograft. Efforts to strengthen transitions of care and to develop practical practice guidelines are needed to improve the outcomes of this vulnerable population.
Assuntos
Transplante de Rim , Nefrologia , Adulto , Humanos , Nefrologistas , Terapia de Imunossupressão , Inquéritos e QuestionáriosRESUMO
Although cellular transplantation remains a relatively small field compared to solid organ transplantation, the prospects for advancement in basic science and clinical care remain bountiful. In this review, notable historical events and the current landscape of the field of cellular transplantation are reviewed with an emphasis on islets (allo- and xeno-), hepatocytes (including bioartificial liver), adoptive regulatory immunotherapy, and stem cells (SCs, specifically endogenous organ-specific and mesenchymal). Also, the nascent but rapidly evolving field of three-dimensional bioprinting is highlighted, including its major processing steps and latest achievements. To reach its full potential where cellular transplants are a more viable alternative than solid organ transplants, fundamental change in how the field is regulated and advanced is needed. Greater public and private investment in the development of cellular transplantation is required. Furthermore, consistent with the call of multiple national transplant societies for allo-islet transplants, the oversight of cellular transplants should mirror that of solid organ transplants and not be classified under the unsustainable, outdated model that requires licensing as a drug with the Food and Drug Administration. Cellular transplantation has the potential to bring profound benefit through progress in bioengineering and regenerative medicine, limiting immunosuppression-related toxicity, and providing markedly reduced surgical morbidity.
Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Transplantes , Humanos , Tolerância Imunológica , Terapia de Imunossupressão , Células-TroncoRESUMO
Belatacept results in improved kidney transplant outcomes, but utilization has been limited by logistical barriers related to monthly (q1m) intravenous infusions. Every 2-month (q2m) belatacept has potential to increase utilization, therefore we conducted a randomized noninferiority trial in low immunologic risk renal transplant recipients greater than 1-year posttransplant. Patients on belatacept were randomly assigned to q1m or q2m therapy. The primary objective was a noninferiority comparison of renal function (eGFR) at 12 months with a noninferiority margin (NIM) of 6.0 ml/min/1.73 m2 . One hundred and sixty-six participants were randomized to q1m (n = 82) or q2m (n = 84) belatacept, 163 patients received treatment, and 76 q1m and 77 q2m subjects completed the 12-month study period. Every 2-month belatacept was noninferior to q1m, as the difference in mean eGFR adjusted for baseline renal function did not exceed the NIM. Two-month dosing was safe and well tolerated, with no patient deaths or graft losses. Four rejection episodes and three cases of donor-specific antibodies (DSAs) occurred among q2m subjects; however, only one rejection and one instance of DSA were observed in subjects adherent to the study protocol. Every 2-month belatacept therapy may facilitate long-term utilization of costimulation blockade, but future multicenter studies with long-term follow-up will further elucidate immunologic risk. (ClinicalTrials.gov NCT02560558).
Assuntos
Transplante de Rim , Abatacepte/uso terapêutico , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Transplante de Rim/efeitos adversos , TransplantadosRESUMO
The return to dialysis after allograft failure is associated with increased morbidity and mortality. This transition is made more complex by the rising numbers of patients who seek repeat transplantation and therefore may have indications for remaining on low levels of immunosuppression, despite the potential increased morbidity. Management strategies vary across providers, driven by limited data on how to transition off immunosuppression as the allograft fails and a paucity of randomized controlled trials to support one approach over another. In this review, we summarize the current data available for management and care of the failing allograft. Additionally, we discuss a suggested plan for immunosuppression weaning based upon the availability of re-transplantation and residual allograft function. We propose a shared-care model in which there is improved coordination between transplant providers and general nephrologists so that immunosuppression management and preparation for renal replacement therapy and/or repeat transplantation can be conducted with the goal of improved outcomes and decreased morbidity in this vulnerable patient group.
Assuntos
Transplante de Rim , Aloenxertos , Humanos , Imunossupressores , Rim , Diálise Renal , Transplante HomólogoRESUMO
The current American Society of Transplantation (AST) accredited transplant fellowship programs in the United States provide no structured formal training in leadership and administration which is essential for successfully running a transplant program. We conducted a survey of medical directors of active adult kidney and kidney-pancreas transplant programs in the United States about their demographics, training pathways, and roles and responsibilities. The survey was emailed to 183 medical directors, and 123 (67.2%) completed the survey. A majority of respondents were older than 50 years (61%), males (80%), and holding that position for more than 10 years (47%). Only 51% of current medical directors had taken that position after completing a one-year transplant fellowship, and 58% took on the role with no prior administrative or leadership experience. The medical directors reported spending a median 50%-75% of time in clinical responsibilities, 25%-50% of time in administration, and 0%-25% time in research. The survey also captured various administrative roles of medical directors vis-à-vis other transplant leaders. The study, designed to be the starting point of an improvement initiative of the AST, provided important insight into the demographics, training pathways, roles and responsibilities, job satisfaction, education needs, and training gaps of current medical directors.
Assuntos
Internato e Residência , Diretores Médicos , Adulto , Educação de Pós-Graduação em Medicina , Bolsas de Estudo , Humanos , Rim , Masculino , Pâncreas , Inquéritos e Questionários , Estados UnidosRESUMO
The coronavirus disease 2019 (COVID-19) pandemic poses unprecedented challenges to the transplant community, including organ procurement organizations (OPOs), transplant centers, regulatory agencies, and recipient candidates. Access to timely, accurate information on the status of deceased donor viral infection is essential in determining organ acceptance. The Organ Procurement and Transplantation Network expeditiously added fields to collect these data; however, use of the data collection fields was not uniform nationally. Standardized, field-defined data capture and reporting are vital to ensure optimal organ utilization during this pandemic, and to prepare the community for subsequent challenges.
Assuntos
COVID-19 , Obtenção de Tecidos e Órgãos , Humanos , Políticas , SARS-CoV-2 , Doadores de TecidosRESUMO
BACKGROUND: Due to a substantial decline in pancreas transplantation (PT) across the United States over the past 15 years, we sought to understand the perceptions and practices of US PT programs. METHODS: Surveys were sent to members of the American Society of Transplantation Surgeons and the American Society of Transplantation by email and professional society postings between August 2019 and November 2019. RESULTS: One hundred twenty three responses were recorded from 56 unique programs. Program characteristics were obtained from the Scientific Registry of Transplant Recipients. Respondents were transplant surgeons (71%), transplant nephrologists (17%), trainees (9%), and allied professionals (3%). Programs were defined according to annual volume as: low (<5 PT/year), intermediate (6-20), or high (>20). High-volume programs reported that these factors were most important for increased PT: expansion of recipient selection, more aggressive donor utilization, and hiring of PT program-specific personnel. At both the program and national level, the vast majority (82% and 79%, respectively) felt the number of PTs currently performed are not in balance with patients' needs. CONCLUSIONS: Overall, programs reported that the option of PT is not offered adequately to diabetic patients and that strategies to maintain higher PT volume are most evident at intermediate, and especially, high-volume programs.
Assuntos
Transplante de Rim , Transplante de Pâncreas , Humanos , Inquéritos e Questionários , Doadores de Tecidos , Transplantados , Estados UnidosRESUMO
Recent evidence suggests that belatacept reduces the durability of preexisting antibodies to class I and class II human leukocyte antigens (HLAs). In this case series of 163 highly sensitized kidney transplant candidates whose calculated panel-reactive antibody (cPRA) activity was ≥98% to 100%, the impact of belatacept on preexisting HLA antibodies was assessed. Of the 163 candidates, 72 underwent transplantation between December 4, 2014 and April 15, 2017; 60 of these transplanted patients remained on belatacept consecutively for at least 6 months. We observed a decrease in the breadth and/or strength of HLA class I antibodies as assessed by FlowPRA in belatacept-treated patients compared to controls who did not receive belatacept. Specifically, significant HLA antibody reduction was evident for class I (P < .0009). Posttransplant belatacept-treated patients also had a clinically significant reduction in their cPRA compared to controls (P < .01). Collectively, these findings suggest belatacept can reduce HLA class I antibodies in a significant proportion of highly sensitized recipients and could be an option to improve pretransplant compatibility with organ donors.
Assuntos
Abatacepte/uso terapêutico , Antígenos HLA/efeitos dos fármacos , Imunossupressores/uso terapêutico , Transplante de Rim , Adulto , Feminino , Humanos , Terapia de Imunossupressão/métodos , Masculino , Pessoa de Meia-Idade , TransplantadosRESUMO
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.
Assuntos
Fragilidade/fisiopatologia , Falência Renal Crônica/cirurgia , Transplante de Rim/normas , Idoso , Humanos , Fatores de RiscoRESUMO
The current mainstay of immunotherapy in clinical transplantation is T lymphocyte directed. However, it has long been appreciated that the emergence of an alloimmune response mounted by the B lymphocyte compartment and detectable as donor-specific antibodies is a critical challenge to long-term graft survival. Thus, achieving robust transplantation tolerance will require induction of tolerance in both the T- and B-cell compartments. Here we propose that the natural developmental propensity of the B-lymphocyte compartment acquisition of tolerance to self-antigens can be recapitulated to achieve humoral transplantation tolerance. It is our contention B-lymphocyte directed induction immunotherapy would be an important component of emerging strategies for induction of Transplantation tolerance.
Assuntos
Fator Ativador de Células B/metabolismo , Subpopulações de Linfócitos B/citologia , Isoanticorpos/biossíntese , Isoantígenos/imunologia , Tolerância ao Transplante/imunologia , Animais , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/transplante , Humanos , Imunoterapia/métodos , Isoanticorpos/imunologia , Depleção Linfocítica/métodosRESUMO
UNLABELLED: Priority is given to patients with hepatocellular carcinoma (HCC) to receive liver transplants, potentially causing significant regional disparities in organ access and possibly outcomes in this population. Our aim was to assess these disparities by comparing outcomes in long waiting time regions (LWTR, regions 5 and 9) and short waiting time regions (SWTR regions 3 and 10) by analyzing the United Network for Organ Sharing (UNOS) database. We analyzed 6,160 HCC patients who received exception points in regions 3, 5, 9, and 10 from 2002 to 2012. Data from regions 5 and 9 were combined and compared to data from regions 3 and 10. Survival was studied in three patient cohorts: an intent-to-treat cohort, a posttransplant cohort, and a cohort examining overall survival in transplanted patients only (survival from listing to last posttransplant follow-up). Multivariate analysis and log-rank testing were used to analyze the data. Median time on the list in the LWTR was 7.6 months compared to 1.6 months for SWTR, with a significantly higher incidence of death on the waiting list in LWTR than in SWTR (8.4% versus 1.6%, P < 0.0001). Patients in the LWTR were more likely to receive loco-regional therapy, to have T3 tumors at listing, and to receive expanded-criteria donor (ECD) or donation after cardiac death (DCD) grafts than patients in the SWTR (P < 0.0001 for all). Survival was significantly better in the LWTR compared to the SWTR in all three cohorts (P < 0.0001 for all three survival points). Being listed/transplanted in an SWTR was an independent predictor of poor patient survival on multivariate analysis (P < 0.0001, hazard ratio = 1.545, 95% confidence interval 1.375-1.736). CONCLUSION: This study provides evidence that expediting patients with HCC to transplant at too fast a rate may adversely affect patient outcomes.
Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Obtenção de Tecidos e Órgãos , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Listas de EsperaRESUMO
BACKGROUND: Long-lived plasma cells (PCs) that form after alloantigen sensitization produce donor-specific alloantibodies that generate a positive serum crossmatch and preclude transplantation. New approaches for desensitization, including PC depletion with proteasome inhibition, show promise but carry considerable toxicity. Recently, eosinophils have been shown to govern PC persistence. Interleukin 5 (IL-5) depletion is known to reduce eosinophils in human asthmatics. We hypothesized that treatment with an anti-IL-5 antibody can deplete alloreactive PCs, reduce donor-specific alloantibodies, and serve as a less toxic alternative to proteasome inhibition. METHODS: BALB/c mice were sensitized with B6 skin allografts. Starting at 8 wk after sensitization, control mice received injections of phosphate-buffered saline, whereas experimental mice received weekly injections of an anti-IL-5 antibody. PCs were enumerated by enzyme-linked immunosorbent spot after 8 wk. RESULTS: All control and experimental recipients of skin allografts developed positive crossmatches when screened at 8 wk after sensitization. All experimental mice treated with anti-IL-5 showed a reduction in their total PC numbers. Also, in contrast to the known adverse effects of proteasome inhibition, experimental mice treated with anti-IL-5 exhibited negligible weight loss or lymphopenia. CONCLUSIONS: Treatment with anti-IL-5 is sufficient to reduce, but not eliminate, alloreactive PCs in the bone marrow. This is because of the targeted reduction of eosinophils leading to a reduction in the PC survival factors a proliferation-inducing ligand and IL-6. Generalized toxicity was not observed in experimental mice. Overall, IL-5 directed immunotherapy can eliminate PC's but is unlikely to be a clinically significant desensitization strategy given the persistence of DSA.
Assuntos
Anticorpos/farmacologia , Dessensibilização Imunológica/métodos , Imunoterapia/métodos , Interleucina-5/antagonistas & inibidores , Plasmócitos/imunologia , Transplante de Pele , Animais , Anticorpos/imunologia , Medula Óssea/imunologia , Medula Óssea/metabolismo , Eosinófilos/citologia , Eosinófilos/imunologia , Interleucina-5/imunologia , Interleucina-6/imunologia , Interleucina-6/metabolismo , Isoanticorpos/imunologia , Isoantígenos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Plasmócitos/citologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismoRESUMO
PURPOSE OF REVIEW: To update the reader on the recent literature in liver, kidney, pancreas, and intestine static cold preservation, and to identify which solutions are most advantageous for each organ. RECENT FINDINGS: The comparison of randomized trials of histidine-tryptophan-ketoglutarate (HTK), Celsior, and University of Wisconsin solutions has shown equivalent risk of delayed graft function after kidney transplantation. Similar outcomes have been observed after pancreas preservation with University of Wisconsin, HTK, and Celsior solution. In live-donor liver transplantation, University of Wisconsin and HTK solution have shown equivalent results, whereas in the recent trials of deceased-donor liver transplantation, University of Wisconsin, HTK, and Celsior solutions have shown equivalence. Contrary to the most clinical trials, national registry data in kidney, pancreas, and liver transplantation demonstrate more detrimental effects and earlier graft loss after preservation with HTK versus University of Wisconsin solution. Early outcomes after intestinal transplantation with University of Wisconsin or HTK solution have shown no significant difference and animal studies indicate intraluminal preservation may be beneficial. SUMMARY: The University of Wisconsin solution is the standard criterion static cold preservation for the procurement of liver, kidney, pancreas, and intestine. University of Wisconsin, HTK, and Celsior solutions all provide similar allograft outcomes in most clinical trials, but subtle differences have become more apparent in the recent studies and registry reports.
Assuntos
Criopreservação/métodos , Intestinos , Rim , Fígado , Soluções para Preservação de Órgãos , Pâncreas , Abdome , Adenosina , Aloenxertos , Alopurinol , Dissacarídeos , Eletrólitos , Glucose , Glutamatos , Glutationa , Histidina , Humanos , Insulina , Manitol , Transplante de Órgãos , Cloreto de Potássio , Procaína , Rafinose , Traumatismo por Reperfusão/prevenção & controle , Doadores de TecidosRESUMO
BACKGROUND: Pancreas transplant biopsy practices for the diagnosis of rejection or other pathologies are not well described. METHODS: We conducted a survey of staff at US pancreas transplant programs (March 22, 2022, to August 22, 2022) to assess current program practices and perceptions about the utility and challenges in the performance and interpretation of pancreas allograft biopsies. RESULTS: Respondents represented 65% (76/117) of active adult pancreas transplant programs, capturing 66% of recent pancreas transplant volume in the United States. Participants were most often nephrologists (52%), followed by surgeons (46%), and other staff (4%). Pancreas allograft biopsies were performed mostly by interventional radiologists (74%), followed by surgeons (11%), nephrologists (8%), and gastroenterologists (1%). Limitations in the radiologist's or biopsy performer's comfort level or expertise to safely perform a biopsy, or to obtain sufficient/adequate samples were the two most common challenges with pancreas transplant biopsies. Pancreas transplant biopsies were read by local pathologists at a majority (86%) of centers. Challenges reported with pancreas biopsy interpretation included poor reliability, lack of reporting of C4d staining, lack of reporting of rejection grading, and inconclusive interpretation of the biopsy. Staff at a third of responding programs (34%) stated that they rarely or never perform pancreas allograft biopsies and treat presumed rejection empirically. CONCLUSIONS: This national survey identified significant variation in clinical practices related to pancreas allograft biopsies and potential barriers to pancreas transplant utilization across the United States. Consideration of strategies to improve program experience with percutaneous pancreas biopsy and to support optimal management of pancreas allograft rejection informed by histology is warranted.