Immunological Risk in Recipients of Kidney Transplants from Extended Criteria Donors

Background: Determining if a kidney from a marginal donor is likely to elicit a strong and specific immune response, leading to an increased risk of acute rejection, is of importance in renal transplantation.

Methods: In this study, we analysed the effect of extended criteria donor (ECD) on the incidence of biopsy-proven acute rejection (BPAR) and the effect of immunological risk factors on graft outcome in a large cohort of kidney transplant recipients (n = 2121 patients) grafted with ECD (n = 656 patients) or optimal donor (OD) (n = 1465 patients).

Results: The incidence of BPAR was not statistically different between the ECD group recipients (105/656, 16%) and the OD group recipients (251/1465, 17%) (P = 0.52). These values remained similar after adjustment for immunological risk [defined as retransplantation and/or panel-reactive antibody (PRA) level >20%] (P = 0.92 for patients with immunological risk and P = 0.47 for patients without immunological risk). We next analysed the death-censored graft survival data for OD and ECD groups, as a function of immunological status, and found that the immunological risk factor did not affect graft survival in ECD transplant recipients (P = 0.64).

Conclusion: Although our groups were not homogenous, our study did not reveal an increased risk of acute rejection in recipients of ECD allograft.