INFLUENCE OF HLA MATCHING ON REJECTIONS AND SHORT-TERM AND LONG-TERM PRIMARY CADAVERIC ALLOGRAFT SURVIVAL

Distribution of cadaveric donor kidneys, based upon the donor-recipient HLA match grade, remains one of the major controversies in transplantation. To determine whether matching results in fewer rejection episodes and better graft survival, we retrospectively studied our single-center patient population of 683 cyclosporine-prednisone-treated primary cadaveric renal allograft recipients. For 237 recipients of well-matched HLA A, B kidneys (less than or equal to 2 HLA A, B mismatches [MM]) the 1-, 3-, 5-, and 7-year graft survivals of 76%, 66%, 62%, and 61%, respectively, were not significantly different from those of 71%, 65%, 63%, and 63%, respectively, for the 446 poorly matched HLA A, B (>2 HLA A, B MM) recipients. Similarly, the 1-, 3-, 5-, and 7-year graft survivals for the 307 recipients of well-matched HLA-DR kidneys (0 or 1 DR MM) of 74%, 65%, 63%, and 61%, respectively, were not significantly different from those of 72%, 65%, 63%, and 62%, respectively, for the 366 poorly matched (2 DR MM) recipients. Patient survivals were comparable at each time point for well- vs. poorly matched recipients. Similarly, donor-recipient HLA A, B, and DR matching was not beneficial in retransplant recipients who were transplanted following negative NIH and antiglobulin (AHG) crossmatches when testing both historical (high-PRA) and pretransplant sera. Since rejection episodes may be a more sensitive indicator of immune response than graft loss, we also analyzed the relationship between donor-recipient HLA match grade and posttransplant rejections. A total of 60% (n=413) of recipients experienced no rejections and had 1-, 3-, 5-, and 7-year graft survivals of 82%, 78%, 74%, and 73%, respectively; 32% (n=215) of patients who experienced 1 rejection had 1-, 3-, 5-, and 7-year graft survivals of 58%, 48%, 44%, and 43%, respectively (P<0.001 for graft survival of 0 vs. 1 rejection). The remaining 8% (n=55) of recipients experienced more than 1 (>1) rejection and had 1-, 3-, 5-, and 7-year graft survivals of 62%, 38%, 36%, and 36%, respectively (P<0.001 for graft survival of 0 vs. >1 rejection and P<0.01 for graft survival of 1 vs. >1 rejection). The mean numbers of rejections/patient experienced by well-matched vs. poorly matched recipients were comparable and not significantly different. Finally, while no differences were observed for the graft survivals of the 254 untransfused vs. the 401 transfused recipients, transfused recipients did experience significantly (P<0.01) fewer rejections than untransfused recipients. Therefore, our data do not support the notion that HLA A, B, and DR donor-recipient matching impacts graft survival or rejection.