Predictive value of donor kidney quality assessment and risk quantification scores on 5-year outcomes of deceased donor kidney transplantation.

Abstract

Due to the excess demand for deceased donor kidneys, risk quantification scores were developed to help with kidney allocation. The kidney donor risk index (KDRI) is used in the US kidney allocation system. We currently use expanded criteria (UNOS) and Remuzzi scoring for allocation of deceased donor kidneys and the utility of KDRI in our cohort is unknown. We aim to evaluate the association of KDRI with relation to 5year graft and patient survival. Retrospective cohort study of 225 adults who received a deceased donor kidney transplant between 1 Nov 2005 and 30 June 2014. Patients were followed up for 5years or until graft-loss or death. Implant biopsies of donor kidneys were done and the Remuzzi score was calculated. The median age was 48 (IQR 42, 52.5) years and 50.7% were male. KDRI-USA, KDRI-THAI, and KDRI-AUST were found to have no correlation with 5year graft survival. Donor characteristics which define an expanded criteria donor kidney, not associated with 5year graft survival are age (p = 0.58), terminal creatinine (p = 0.71) and history of hypertension (p = 0.35). Donor cerebrovascular accident (CVA) as a cause of death (p = 0.02) and Remuzzi score were associated with graft survival at 5years, with 75.8% with Remuzzi score ≤ 3 vs 24.2% with Remuzzi score of > 3 achieving 5year graft survival (p = 0.001). The association of KDRI with graft and patient survival was not demonstrated in our cohort. Histological assessment of the transplant kidney remains the best method of predicting long-term survival during donor selection.