Deceased donor procurement biopsy practices, interpretation, and histology-based decision-making: A survey of US kidney transplant centers

INTRODUCTION: The utility of kidney procurement biopsies is controversial. Understanding the current landscape of how clinicians obtain and use biopsies in organ evaluation may help inform consensus-building efforts. METHODS: An electronic survey was distributed to clinicians at US kidney transplant programs (April 22, 2021-June 30, 2021) to evaluate donor biopsy indications, frequency, processing and interpretation, and impact of findings on practices. RESULTS: Responses from staff involved in organ acceptance (73% surgeons, 20% nephrologists, 6% coordinators) at 95 transplant centers were analyzed, representing 40% of US transplant centers and 50% of recent deceased donor kidney transplant volume. More than a third of centers (35%) reported obtaining procurement biopsies on most-to-all kidneys. Most clinicians decided when to biopsy jointly with the Organ Procurement Organization (OPO) (82%) based on formal criteria for the decision (72%), although 41% reported having requested a biopsy outside of the criteria. Most respondents used a semiquantitative scoring system for interpretation (57%). Many respondents reported rarely or never having access to renal specialty pathologists (37%) or to telepathology (59%). Most respondents reported that a favorable biopsy result would encourage them to accept a marginal donor kidney (72%); nearly half (46%) indicated that an unfavorable biopsy result would lead to decline of a standard criteria kidney. CONCLUSION: Procurement biopsies are commonly used in organ acceptance decisions despite inconsistent access to experienced renal pathologists and heterogeneous approaches to criteria, scoring, and interpretation. Ongoing study and consensus building are needed to direct procurement biopsy practice toward increasing organ utilization and reducing allocation inefficiency

Long-term safety and efficacy of antithymocyte globulin induction: Use of integrated national registry data to achieve ten-year follow-up of 10-10 Study participants

BACKGROUND: Rabbit antithymocyte globulin (rATG, Thymoglobulin®) is the most common induction immunosuppression therapy in kidney transplantation. We applied a database integration strategy to capture and compare long-term (10-year) outcome data for US participants in a clinical trial of rATG versus FDA-approved basiliximab. METHODS: Records for US participants in an international, 1-year, randomized clinical trial comparing rATG and basiliximab induction in deceased donor kidney transplantation were integrated with records from the US national Organ Procurement and Transplantation (OPTN) registry using center, transplant dates, recipient sex, and birthdates. The OPTN captures center-reported acute rejection, graft failure, death, and cancer events, and incorporates comprehensive death records from the Social Security Death Master File. Ten-year outcomes according to randomized induction regimen were compared by Kaplan–Meier analysis (two-sided P). Non-inferiority of rATG was assessed using a one-tailed equivalence test (a-priori equivalence margins of 0–10 %). RESULTS: Of 183 US trial participants, 89 % (n = 163) matched OPTN records exactly; the remainder were matched by extending agreement windows for transplant and birthdates. Matches were validated by donor and recipient blood types. By Kaplan–Meier analysis, 10 years post-transplant, freedom from acute rejection, graft failure, or death was 32.6 % and 24.0 % in the rATG and basiliximab arms, respectively (P = 0.09). The incidence of acute rejection with rATG versus basiliximab induction was 21.0 % versus 32.8 % (P = 0.07). Patient survival (52.5 % versus 52.2 %, P = 0.92) and graft survival (34.3 % versus 30.9 %, P = 0.56) rates were numerically and statistically similar for both arms. Comparison of the composite outcome meets non-inferiority criteria even with a 0 % equivalence margin (one-sided P = 0.04). With a 10 % equivalence margin, the odds that rATG is no worse than basiliximab for 10-year risk of the composite endpoint are >99 %. CONCLUSIONS: Ten years post-transplant, rATG induction has comparable efficacy and safety to FDA-approved basiliximab. Integration of clinical trial records with national registry data can enable long-term monitoring of trial participants in transplantation, circumventing logistical and cost barriers of extended follow-up. TRIAL REGISTRATION: ClinicalTrials.gov NCT00235300 ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13063-015-0891-y) contains supplementary material, which is available to authorized users

The privilege of induction avoidance and calcineurin inhibitors withdrawal in 2 haplotype HLA matched white kidney transplantation

BACKGROUND: White recipients of 2-haplotype HLA-matched living kidney transplants are perceived to be of low immunologic risk. Little is known about the safety of induction avoidance and calcineurin inhibitor withdrawal in these patients. METHODS: We reviewed our experience at a single center and compared it to Organ Procurement and Transplantation Network (OPTN) registry data and only included 2-haplotype HLA-matched white living kidney transplants recipients between 2000 and 2013. RESULTS: There were 56 recipients in a single center (where no induction was given) and 2976 recipients in the OPTN. Among the OPTN recipients, 1285 received no induction, 903 basiliximab, 608 thymoglobulin, and 180 alemtuzumab. First-year acute rejection rates were similar after induction-free transplantation among the center and induced groups nationally. Compared with induction-free transplantation in the national data, there was no decrease in graft failure risk over 13 years with use of basiliximab (adjusted hazard ratio [aHR], 0.86; confidence interval [CI], 0.68-1.08), Thymoglobulin (aHR, 0.92; CI, 0.7-1.21) or alemtuzumab (aHR, 1.18; CI, 0.72-1.93). Among induction-free recipients at the center, calcineurin inhibitor withdrawal at 1 year (n = 27) did not significantly impact graft failure risk (HR,1.62; CI, 0.38-6.89). CONCLUSIONS: This study may serve as a foundation for further studies to provide personalized, tailored, immunosuppression for this very low-risk population of kidney transplant patients

Immune-complex deposits in “pauci-immune” glomerulonephritis: a case report and brief review of recent literature

Anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis is considered a “pauci-immune” disease, characterized by absent or mild glomerular tuft staining for immunoglobulin and/or complement. We describe a 72-year-old man with progressive renal failure over five months who was found to have P-ANCA associated crescentic glomerulonephritis. Renal biopsy also revealed immunofluorescence staining for Immunoglobulin G and C3. Treatment comprised corticosteroids, cyclophosphamide, and plasmapheresis but unfortunately kidney function did not recover, likely due to substantial interstitial fibrosis at diagnosis. This case illustrates that serologic evaluation for ANCAs should not be discounted when immune deposits are present. Prompt diagnosis is warranted

Association of ambient fine particulate matter air pollution with kidney transplant outcomes

Importance: Increased levels of ambient fine particulate matter (PM2.5) air pollution are associated with increased risks for detrimental health outcomes, but risks for patients with kidney transplants (KTs) remain unknown. Objective: To investigate the association of PM2.5 exposure with KT outcomes. Design, Setting, and Participants: This retrospective cohort study was conducted using data on patients who received KTs from 2004 to 2016 who were identified in the national US transplant registry and followed up through March 2021. Multiple databases were linked to obtain data on PM2.5 concentration, KT outcomes, and patient clinical, transplant, and contextual factors. Data were analyzed from April 2020 through July 2021. Exposures: Exposures included post-KT time-dependent annual mean PM2.5 level (in 10 μg/m3) and mean PM2.5 level in the year before KT (ie, baseline levels) in quartiles, as well as baseline annual mean PM2.5 level (in 10 μg/m3). Main Outcomes and Measures: Acute kidney rejection (ie, rejection within 1 year after KT), time to death-censored graft failure, and time to all-cause death. Multivariable logistic regression for kidney rejection and Cox analyses with nonlinear assessment of exposure-response for death-censored graft failure and all-cause death were performed. The national burden of graft failure associated with PM2.5 levels greater than the Environmental Protection Agency recommended level of 12 μg/m3 was estimated. Results: Among 112 098 patients with KTs, 70 522 individuals (62.9%) were older than age 50 years at the time of KT, 68 117 (60.8%) were men, and the median (IQR) follow-up was 6.0 (3.9-8.9) years. There were 37 265 Black patients (33.2%), 17 047 Hispanic patients (15.2%), 48 581 White patients [43.3%]), and 9205 patients (8.2%) of other race or ethnicity. The median (IQR) baseline PM2.5 level was 9.8 (8.3-11.9) μg/m3. Increased baseline PM2.5 level, compared with quartile 1 baseline PM2.5 level, was not associated with higher odds of acute kidney rejection for quartile 2 (adjusted odds ratio [aOR], 0.99; 95% CI, 0.92-1.06) but was associated with increased odds for quartile 3 (aOR, 1.11; 95% CI, 1.04-1.20) and quartile 4 (aOR, 1.13; 95% CI, 1.05-1.23). Nonlinear assessment of exposure-response for graft failure and death showed no evidence for nonlinearity. Increased PM2.5 levels were associated with increased risk of death-censored graft failure (adjusted hazard ratio [aHR] per 10 μg/m3 increase, 1.17; 95% CI, 1.09-1.25) and all-cause death (aHR per 10 μg/m3 increase, 1.21; 95% CI, 1.14-1.28). The national burden of death-censored graft failure associated with PM2.5 above 12 μg/m3 was 57 failures (95% uncertainty interval, 48-67 failures) per year among patients with KTs. Conclusions and Relevance: This cohort study found that PM2.5 level was an independent risk factor associated with acute rejection, graft failure, and death among patients with KTs. These findings suggest that efforts toward decreasing levels of PM2.5 concentration may be associated with improved outcomes after KT

Racial variation in medical outcomes among living kidney donors

BACKGROUND: Data regarding health outcomes among living kidney donors are lacking, especially among nonwhite persons. METHODS: We linked identifiers from the Organ Procurement and Transplantation Network (OPTN) with administrative data of a private U.S. health insurer and performed a retrospective study of 4650 persons who had been living kidney donors from October 1987 through July 2007 and who had post-donation nephrectomy benefits with this insurer at some point from 2000 through 2007. We ascertained post-nephrectomy medical diagnoses and conditions requiring medical treatment from billing claims. Cox regression analyses with left and right censoring to account for observed periods of insurance benefits were used to estimate absolute prevalence and prevalence ratios for diagnoses after nephrectomy. We then compared prevalence patterns with those in the 2005–2006 National Health and Nutrition Examination Survey (NHANES) for the general population. RESULTS: Among the donors, 76.3% were white, 13.1% black, 8.2% Hispanic, and 2.4% another race or ethnic group. The median time from donation to the end of insurance benefits was 7.7 years. After kidney donation, black donors, as compared with white donors, had an increased risk of hypertension (adjusted hazard ratio, 1.52; 95% confidence interval [CI], 1.23 to 1.88), diabetes mellitus requiring drug therapy (adjusted hazard ratio, 2.31; 95% CI, 1.33 to 3.98), and chronic kidney disease (adjusted hazard ratio, 2.32; 95% CI, 1.48 to 3.62); findings were similar for Hispanic donors. The absolute prevalence of diabetes among all donors did not exceed that in the general population, but the prevalence of hypertension exceeded NHANES estimates in some subgroups. End-stage renal disease was identified in less than 1% of donors but was more common among black donors than among white donors. CONCLUSIONS: As in the general U.S. population, racial disparities in medical conditions occur among living kidney donors. Increased attention to health outcomes among demographically diverse kidney donors is needed. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others.

Patterns in use and transplant outcomes among adult recipients of kidneys from deceased donors with COVID-19

IMPORTANCE: While the COVID-19 pandemic enters a new phase and the proportion of individuals with a previous COVID-19 diagnosis increases, the national patterns in kidney use and medium-term kidney transplant (KT) outcomes among patients receiving kidneys from active or resolved COVID-19-positive donors remain unknown. OBJECTIVE: To evaluate the patterns in kidney use and KT outcomes among adult recipients of kidneys from deceased donors with active or resolved COVID-19. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study was conducted using national US transplant registry data from 35 851 deceased donors (71 334 kidneys) and 45 912 adult patients who received KTs from March 1, 2020, to March 30, 2023. EXPOSURE: The exposure was donor SARS-CoV-2 nucleic acid amplification test (NAT) results, with positive NAT results within 7 days before procurement defined as active COVID-19 and positive NAT results 1 week (\u3e7 days) before procurement defined as resolved COVID-19. MAIN OUTCOMES AND MEASURES: Primary outcomes were kidney nonuse, all-cause kidney graft failure, and all-cause patient death. Secondary outcomes were acute rejection (ie, rejection in the first 6 months after KT), transplant hospitalization length of stay (LOS), and delayed graft function (DGF). Multivariable logistic regression analyses were performed for kidney nonuse, rejection, and DGF; multivariable linear regression analyses were performed for LOS; and multivariable Cox regression analyses were performed for graft failure and all-cause death. All models were adjusted for inverse probability treatment weighting. RESULTS: Among 35 851 deceased donors, the mean (SD) age was 42.5 (15.3) years; 22 319 (62.3%) were men and 23 992 (66.9%) were White. Among 45 912 recipients, the mean (SD) age was 54.3 (13.2) years; 27 952 (60.9%) were men and 15 349 (33.4%) were Black. The likelihood of nonuse of kidneys from active or resolved COVID-19-positive donors decreased over time. Overall, kidneys from active COVID-19-positive donors (adjusted odds ratio [AOR], 1.55; 95% CI, 1.38-1.76) and kidneys from resolved COVID-19-positive donors (AOR, 1.31; 95% CI, 1.16-1.48) had a higher likelihood of nonuse compared with kidneys from COVID-19-negative donors. From 2020 to 2022, kidneys from active COVID-19-positive donors (2020: AOR, 11.26 [95% CI, 2.29-55.38]; 2021: AOR, 2.09 [95% CI, 1.58-2.79]; 2022: AOR, 1.47 [95% CI, 1.28-1.70]) had a higher likelihood of nonuse compared with kidneys from donors without COVID-19. Kidneys from resolved COVID-19-positive donors had a higher likelihood of nonuse in 2020 (AOR, 3.87; 95% CI, 1.26-11.90) and 2021 (AOR, 1.94; 95% CI, 1.54-2.45) but not in 2022 (AOR, 1.09; 95% CI, 0.94-1.28). In 2023, kidneys from both active COVID-19-positive donors (AOR, 1.07; 95% CI, 0.75-1.63) and resolved COVID-19-positive donors (AOR, 1.18; 95% CI, 0.80-1.73) were not associated with higher odds of nonuse. No higher risk of graft failure or death was found in patients receiving kidneys from active COVID-19-positive donors (graft failure: adjusted hazard ratio [AHR], 1.03 [95% CI, 0.78-1.37]; patient death: AHR, 1.17 [95% CI, 0.84-1.66]) or resolved COVID-19-positive donors (graft failure: AHR, 1.10 [95% CI, 0.88-1.39]; patient death: AHR, 0.95 [95% CI, 0.70-1.28]). Donor COVID-19 positivity was not associated with longer LOS, higher risk of acute rejection, or higher risk of DGF. CONCLUSIONS AND RELEVANCE: In this cohort study, the likelihood of nonuse of kidneys from COVID-19-positive donors decreased over time, and donor COVID-19 positivity was not associated with worse KT outcomes within 2 years after transplant. These findings suggest that the use of kidneys from donors with active or resolved COVID-19 is safe in the medium term; further research is needed to assess longer-term transplant outcomes