Outcomes of Kidney Transplants From Donors With Stage 3 Acute Kidney Injury Requiring Dialysis: A National Cohort Study.

BACKGROUND: Whether severe donor acute kidney injury (AKI) requiring dialysis affects posttransplant outcomes remains debated and may influence center-level acceptance decisions.

METHODS: This retrospective cohort study of United States deceased-donor kidney transplants (2015-2020) used OPTN data with follow-up through September 2024. Donor AKI was staged by KDIGO 2012 criteria, and dialysis was identified using a validated rule-based natural language processing (NLP) algorithm applied to DonorNet records. The primary outcome was all-cause graft failure (ACGF). Secondary outcomes included delayed graft function (DGF), 1-year estimated glomerular filtration rate (eGFR), and a composite tolerability outcome within 6 months defined as DGF, eGFR <30 mL/min/1.73 m2, graft failure, or death. Models used inverse probability weighting (IPW), clustering by transplant center, and exploratory interpretable machine learning.

RESULTS: Of 74 939 transplants, 24.6% were from AKI donors (Stage 2 7.8%, Stage 3 without dialysis 5.8%, Stage 3 with dialysis 2.1%). DGF increased with AKI severity (Stage 3 with dialysis 54.5% vs Stage 2 38.1%), but adjusted ACGF risk was similar across groups. Donor KDPI and recipient EPTS were stronger predictors of graft failure than AKI stage. Exploratory tolerability analyses showed that early adverse outcomes were driven primarily by recipient age, BMI, dialysis duration, and organ quality, not by donor AKI severity or dialysis.

CONCLUSIONS: Among transplanted kidneys, Stage 3 AKI requiring donor dialysis was associated with higher early DGF but similar adjusted graft survival compared with Stage 2 AKI after accounting for organ quality and recipient risk. These findings reflect outcomes among AKI-affected kidneys accepted for transplantation and should not be generalized to declined or discarded kidneys.