Delayed kidney transplantation in combined liver-kidney transplantation: A validation analysis by the UNOS registry
Am J Transplant
Background: Delayed kidney transplantation (KT) for patients undergoing combined liver-kidney transplant (CLKT) have been suggested to improve outcomes compared to simultaneous KT in CLKT. This study aims to validate the efficacy of delayed KT in CLKT using the UNOS registry. Methods: We examined all adult CLKT from 01/01/2003 to 03/31/2017. Delayed KT in CLKT was defined as the difference between kidney and liver cold ischemia time ≥24hr and simultaneous KT as ≤6hr. Delayed and simultaneous KT in CLKT were matched by propensity scores adjusting for recipient and donor factors. Multivariable cox and logistic models were fitted to compare various outcomes. Results: We analyzed 4460 simultaneous KT and 915 delayed KT in CLKT. Delayed KT was associated with worse 1-year patient (HR = 1.42; P = 0.036), liver (HR = 1.44; P = 0.024), and kidney (HR = 1.45; P =0.021) survival compared to simultaneous KT in those with MELD ≥35. Delayed KT was a protective factor for delayed kidney graft function (DGF) in MELD ≤25 (HR = 0.65; P = 0.039) and ≥35 (HR = 0.67; P = 0.023). No differences in 3, 6, or 12-month eGFR were observed. Conclusions: Delayed KT in CLKT is associated with worse 1-year patient, liver, and kidney survival in MELD ≥35, protective against DGF in recipients with MELD ≤25 and ≥35, and have comparable post-transplant eGFR compared to simultaneous KT. Risk stratification based on MELD should be considered among patients receiving delayed KT in CLKT. (Figure Presented).