Living unrelated donors in kidney transplants - Better long-term results than with non-HLA-identical living related donors?

Background. Given the severe organ shortage and the documented superior res ults obtained with living (vs, cadaver) donor kidney transplants, we have a dopted a very aggressive policy for the use of living donors. Currently, we make thorough attempts to locate a living related donor (LRD) or a living unrelated donor (LURD) before proceeding with a cadaver transplant. Methods. We compared the results of our LURD versus LRD transplants to dete rmine any significant difference in outcome. Results. Between 1/1/84 and 6/30/98, we performed 711 adult kidney transpla nts with non-HLA-identical living donors. Of these, 595 procedures used LRD s and 116 used LURDs, Immunosuppression for both groups was cyclosporine-ba sed, although LURD recipients received 5-7 days of induction therapy (antil ymphocyte globulin or antithymocyte globulin), whereas LRD recipients did n ot. LURD recipients tended to be older, to have inferior HLA matching, and to have older donors than did the LRD recipients (all factors potentially a ssociated with decreased graft survival). Short-term results, including ini tial graft function and incidence of acute rejection, were similar in the t wo groups. LURD recipients had a slightly higher incidence of cytomegalovir us disease (P=NS), We found no difference in patient and graft survival rat es. However, the incidence of biopsy-proven chronic rejection was significa ntly lower among LURD recipients (16.7% for LRD recipients and 10.0% for LU RD recipients at 5 years posttransplant; P=0.05). LRD recipients also had a greater incidence of late (>6 months posttransplant) acute rejection episo des than did the LURD recipients (8.6% vs. 2.6%, P=0.04), The exact reason for these findings is unknown. Conclusion. Although LURD recipients have poorer HLA matching and older don ors, their patient and graft survival rates are equivalent to those of non- HLA-identical LRD recipients. The incidence of biopsy-proven chronic reject ion is lower in LURD transplants. Given this finding and the superior resul ts of living donor (vs, cadaver) transplants, a thorough search should be m ade for a living donor-LRD or LURD-before proceeding with a cadaver transpl ant.