The benefit of exchanging donor kidneys among transplant centers.

Whether kidneys from cadaver donors should be exchanged among transplant centers is controversial. We analyzed the effect of matching for HLA-B and HLA-DR antigens on graft survival in patients treated with cyclosporine. The results in 9369 recipients of kidneys obtained and transplanted in the same center were compared with those in 5553 recipients of kidneys shipped from one center to another. In both patient subgroups, the association of HLA matching with graft survival was statistically significant (P less than 0.0001). Moreover, well-matched exchanged kidneys survived better than poorly matched locally transplanted kidneys. Among patients receiving their first cadaver transplant, graft survival at one year was 13 percentage points higher (P less than 0.0001) in exchanged kidneys without mismatches than in local kidneys with four mismatches. Among patients receiving their second transplant, graft survival was 21 percentage points higher (P less than 0.001). Kidney preservation for up to 48 hours did not affect graft survival significantly. Transplantation of poorly matched local kidneys preserved with a short period of cold ischemia (less than 24 hours) had significantly lower rates of success than did transplantation of well-matched exchanged kidneys with a longer period of cold ischemia (up to 48 hours) (P less than 0.0001). Our data indicate that the exchange of cadaver kidneys among transplant centers to obtain grafts with better HLA matching can improve the success rate of renal transplantation.