Caitlin G. Peterson

Background Antibody‐mediated rejection (AMR) is a major cause of kidney allograft loss. There is a paucity of large‐scale pediatric‐specific data regarding AMR treatment outcomes. Methods Data were obtained from 14 centers within the Pediatric Nephrology Research Consortium. Kidney transplant recipients aged 1–18 years at transplant with biopsy‐proven AMR between 2009 and 2019 and at least 12 months of follow‐up were included. The primary outcome was graft failure or an eGFR <20 mL/min/1.73 m 2 at 12 months following AMR treatment. AMR treatment choice, histopathology, and DSA class were also examined. Results We reviewed 123 AMR episodes. Median age at diagnosis was 15 years at a median 22 months post‐transplant. The primary outcome developed in 27.6%. eGFR <30 m/min/1.73 m 2 at AMR diagnosis was associated with a 5.6‐fold higher risk of reaching the composite outcome. There were no significant differences in outcome by treatment modality. Histopathology scores and DSA class at time of AMR diagnosis were not significantly associated with the primary outcome. Conclusions In this large cohort of pediatric kidney transplant recipients with AMR, nearly one‐third of patients experienced graft failure or significant graft dysfunction within 12 months of diagnosis. Poor graft function at time of diagnosis was associated with higher odds of graft failure.

Background The 2014 Kidney Allocation System (KAS) introduced longevity matching for adult candidates using the Estimated Post‐Transplant Survival (EPTS) score, which includes candidate age, time on dialysis, diabetes status, and number of previous solid organ transplants. The proposed continuous distribution framework may expand the use of this attribute to pediatric candidates, but there is no data on its performance among pediatric kidney transplant recipients. Methods We performed a retrospective cohort study of 6800 pediatric kidney transplant recipients from 2001 to 2011 using Organ Procurement and Transplantation Network (OPTN) data. EPTS score was calculated for each patient and compared to reported patient survival to estimate the validity of the score in children. Results The median age of patients was 14.01 years (IQR 9.29–16.37 years), and dialysis vintage was 0.67 years (IQR 0–1.82 years). 18.2% of the cohort had a prior transplant and 1% had diabetes. Median EPTS score was 2 (IQR 1–2). Seven percent of patients died during the study period and 54.7% of the cohort was censored prior to 10 years. The c‐statistic was 0.505 (95% CI: 0.49–0.53). Conclusion Overall, EPTS is not a valid predictor of patient survival among pediatric kidney transplant recipients.