A single-center cohort study to define the role of pretransplant biopsy score in the long-term outcome of kidney transplantation.

Background. The role of pretransplant biopsy in defining the quality of kidney grafts is still debated. The aim ofthis study was to investigate the influence of pretransplant biopsy score on long-term graft outcome.Methods. In a retrospective cohort study, we analyzed 372 recipients of single kidney transplantation (SKT) fromdeceased donors between 1997 and 2007, with an available pretransplant biopsy. We evaluated 5- and 10-year graftsurvival, incidence of delayed graft function, and estimated glomerular filtration rate at 1 and 5 years.Results. Graft survival at 5 and 10 years was significantly better for recipients with a score of 0 compared to trans-plants with a score of 1 to 5, whereas we did not observe any significant difference among transplants with a score of1 through 4. Survival of kidneys with a score of 5 was significantly worse compared to grafts with a score of 1 to 4.In a multivariate Cox model, only pretransplant histological score was significantly associated with graft survival.Transplants with a score of 0 and 5 had the best and the worst graft function, respectively, both at 1 and 5 years,whereas we did not observe any difference among patients with a score of 1 through 4. In a multivariate logisticregression, pretransplant histological score was independently associated with the prevalence of an estimated glomeru-lar filtration rate less than 30 mL/min at 5 years. Finally, delayed graft function rate was significantly higher in recipientswith a score of 5 compared to patients with a score of 1 to 4 and score of 0.Conclusions. Our data suggest that 1) pretransplant histological score may predict long-term graft outcome and 2)allocation of kidneys with a score of 4 to SKT provides an acceptable long-term graft function and survival.Keywords: Renal transplantation, Graft outcome, Pretransplant renal biopsy, Expanded criteria donors.(Transplantation 2014;97: 934Y939)