Broad organ acceptance and equitable access to early kidney transplantation.

BACKGROUND: Broad organ acceptance can increase early kidney transplantation (KTX) within <1-year of dialysis initiation while improving access inequity. METHODS: Single-center data of adult isolated deceased-donor KTX recipients between 2013 and 2020 were stratified into three 2.5-year periods before-, early after-, and late after our center's deceased-donor organ acceptance practice change, excluding a 6-month implementation period. Outcomes were assessed within five recipient subgroups based on demographic and clinical characteristics. RESULTS: Of 704 recipients, the frequency of early KTX was 22% pre-change, 36% early post-change, and 34% late post-change. Given similar post-change frequencies of early KTX, post-change eras were combined to improve analytic power of subgroup analyses. After the organ acceptance practice change (vs. pre-change), the likelihood of early KTX increased variably within historically underserved groups, including recipients who were older (37%-39%, p = .859), Black (10%-21%, p = .136), female (21%-37%, p = .034), diabetic (13%-32%, p = .010), and BMI≥35 kg/m2 (20%-34%, p = .007). Despite the practice change, Black recipients continued to experience less early KTX compared to non-Black recipients. The likelihood of delayed graft function was significantly increased (p < .001), and 1-year creatinine was significantly higher (p < .001) post-practice change, but between-era risk-adjusted death-censored graft survival was similar. CONCLUSIONS: Transition to broader donor acceptance was associated with more early KTXs among historically underserved patient subgroups. However, the effect was non-significant among Black recipients, suggesting the need for additional strategies to impact early transplant access for this population. Studies of broad organ acceptance are needed to examine both access and outcomes.

Tocilizumab for the treatment of chronic antibody mediated rejection in kidney transplant recipients.

BACKGROUND: Chronic active antibody-mediated rejection (CAAMR) constitutes a dominant form of late allograft failure. Several treatment strategies directed at CAAMR have been attempted but proven ineffective at delaying kidney function decline or reducing donor-specific antibodies (DSA). We describe our single-center experience using tocilizumab in patients with CAAMR. METHODS: This is a retrospective analysis using electronic medical records. 38 kidney transplant recipients at Columbia University Irving Medical Center who had been prescribed tocilizumab and followed for at least 3 months between August 2013 through December 2019 were included. RESULTS: Tocilizumab use was associated with a decrease in the rate of estimated glomerular filtration rate (eGFR) decline in the 6 months following treatment initiation as compared to the 3 months before tocilizumab was initiated (difference between slopes before and after initiation of treatment = 2.6 mL/min/1.73 m2 (SE = .8, p = .002) per month for up to 6 months following Tocilizumab initiation). Allograft biopsies showed significant improvement in interstitial inflammation scores (score 1(0,1) to 0 (0,1), p = .03) while other histologic scores remained stable. There was no significant change in proteinuria or DSA titers post-treatment with tocilizumab. CONCLUSIONS: Treatment of CAAMR with tocilizumab was associated with a decrease in the rate of eGFR decline and a reduction in interstitial inflammation scores in patients with CAAMR.

High rate of renal recovery in survivors of COVID-19 associated acute renal failure requiring renal replacement therapy.

INTRODUCTION: A large proportion of patients with COVID-19 develop acute kidney injury (AKI). While the most severe of these cases require renal replacement therapy (RRT), little is known about their clinical course. METHODS: We describe the clinical characteristics of COVID-19 patients in the ICU with AKI requiring RRT at an academic medical center in New York City and followed patients for outcomes of death and renal recovery using time-to-event analyses. RESULTS: Our cohort of 115 patients represented 23% of all ICU admissions at our center, with a peak prevalence of 29%. Patients were followed for a median of 29 days (2542 total patient-RRT-days; median 54 days for survivors). Mechanical ventilation and vasopressor use were common (99% and 84%, respectively), and the median Sequential Organ Function Assessment (SOFA) score was 14. By the end of follow-up 51% died, 41% recovered kidney function (84% of survivors), and 8% still needed RRT (survival probability at 60 days: 0.46 [95% CI: 0.36-0.56])). In an adjusted Cox model, coronary artery disease and chronic obstructive pulmonary disease were associated with increased mortality (HRs: 3.99 [95% CI 1.46-10.90] and 3.10 [95% CI 1.25-7.66]) as were angiotensin-converting-enzyme inhibitors (HR 2.33 [95% CI 1.21-4.47]) and a SOFA score >15 (HR 3.46 [95% CI 1.65-7.25). CONCLUSIONS AND RELEVANCE: Our analysis demonstrates the high prevalence of AKI requiring RRT among critically ill patients with COVID-19 and is associated with a high mortality, however, the rate of renal recovery is high among survivors and should inform shared-decision making.

Impact of Deceased Donor Kidney Procurement Biopsy Technique on Histologic Accuracy.

INTRODUCTION: The factors that influence deceased donor kidney procurement biopsy reliability are not well established. We examined the impact of biopsy technique and pathologist training on procurement biopsy accuracy. METHODS: We retrospectively identified all deceased donor kidney-only transplants at our center from 2006 to 2016 with both procurement and reperfusion biopsies performed and information available on procurement biopsy technique and pathologist (n = 392). Biopsies were scored using a previously validated system, classifying "suboptimal" histology as the presence of at least 1 of the following: glomerulosclerosis ≥11%, moderate/severe interstitial fibrosis/tubular atrophy, or moderate/severe vascular disease. We calculated relative risk ratios (RRR) to determine the influence of technique (core vs. wedge) and pathologist (renal vs. nonrenal) on concordance between procurement and reperfusion biopsy histologic classification. RESULTS: A total of 171 (44%) procurement biopsies used wedge technique, and 221 (56%) used core technique. Results of only 36 biopsies (9%) were interpreted by renal pathologists. Correlation between procurement and reperfusion glomerulosclerosis was poor for both wedge (r 2 = 0.11) and core (r 2 = 0.14) biopsies. Overall, 34% of kidneys had discordant classification on procurement versus reperfusion biopsy. Neither biopsy technique nor pathologist training was associated with concordance between procurement and reperfusion histology, but a larger number of sampled glomeruli was associated with a higher likelihood of concordance (adjusted RRR = 1.12 per 10 glomeruli, 95% confidence interval = 1.04-1.22). CONCLUSIONS: Biopsy technique and pathologist training were not associated with procurement biopsy histologic accuracy in this retrospective study. Prospective trials are needed to determine how to optimize procurement biopsy practices.