A new allocation plan for renal transplantation

Background. A novel plan of renal allograft allocation has been conducted b y United Network for Organ Sharing Region 1 transplant centers since Septem ber 3, 1996, based upon HLA matching, time waiting, and population distance points. The objectives of this plan were to achieve a balance between incr easing the opportunity of renal transplantation for those patients listed w ith long waiting times and promoting local organ donor availability. Methods. A single list of candidates was formulated for each cadaver donor, assigning a maximum of 8 points for time waiting, a maximum of 8 points fo r population distance from the donor hospital, and HLA points based upon th e degree of B/DR mismatch. Additional points were awarded to a cross-match- negative patient with a panel-reactive antibody of >80%, and to pediatric p atients. Results. The total number of kidneys transplanted to patients who had waite d >3 years was 100 (46%), and to patients who had waited >2.5-3 years was 2 9 (13%). However, the total number of kidneys transplanted to patients with the maximum population distance points was only 72 (33%), Thus, although t he plan achieved a favorable distribution of kidneys to patients with longe r waiting times (nearly 60%), the other, equally important objective of pro moting local donor availability was not initially accomplished. Moreover, m inor HLA B/DR differences between the donor and the recipient (i.e., not ph enotypically matched) were unexpectedly consequential in determining alloca tion. As a result of these observations, the following adjustments were made in t he plan las of December 3, 1997): a maximum of 10 points for population dis tance, a maximum of 8 points for time waiting (both by a linear correlation ), and the retention of HLA points for 0 B/DR mismatch only. After these in terval changes, the percentage of patients receiving a kidney with some pop ulation distance points increased from 85% to 96%. Conclusions. We have shown that a heterogeneous region of multiple transpla nt centers can devise land modify) an innovative and balanced plan that pro vides an equitable system of allocation for an ever-increasing number of pa tients.