Trend, not severity, of acute kidney injury affects graft outcome in deceased donor kidney transplantation

Deceased donor kidneys (DDKs) with acute kidney injury (AKI) are difficult to allocate for fear of the expected graft outcome. We aimed to evaluate the impact of donors' AKI severity and trend on graft outcomes in DDK transplantation. This was a retrospective study of DDK transplantation performed from 2005 to 2014. Based on maximum and terminal serum creatinine values before transplantation, the AKI trends were categorized as improving or worsening. Of 413 DDKs, 275 developed AKI: 177 stage 1, 52 stage 2, and 46 stage 3. DDKs with AKI had 212 improving AKI and 63 worsening AKI. Graft outcomes were similar based on AKI stage. Worsening AKI did not affect delayed graft function development; however, it significantly elevated graft failure risk even after adjusting for AKI stage and Kidney Donor Risk Index. Graft survival of the improving group was similar to DDKs with no AKI. This study showed that AKI severity of DDKs did not affect overall graft outcomes. Notably, DDKs with improving AKI showed a similar graft survival rate to DDKs without AKI, although worsening AKI had a worse prognosis. Consideration of the AKI trend, rather than its severity, is needed when DDKs with AKI are allocated.