The role of HLA matching in renal transplantation: experience from one center

The influence of serology-based HLA matching on the risk of acute rejection episodes and of graft loss was analyzed in a material of 678 living donor (LD) and 997 cadaveric donor (CD) renal transplantations performed in our center in the period 1989-97. In LD transplantation, recipients of HLA-identical sibling grafts had the lowest rejection risk and the best graft survival, with a half-life estimate of 30 years. One-HLA-haplotype mismatched grafts did better than two-haplotype mismatched related or unrelated donor grafts. Matching for HLA-DR significantly reduced the rejection risk of one-haplotype mismatched grafts. In CD first transplants, HLA-DR matched grafts had a lower incidence of rejection and better survival than HLA-DR mismatched grafts. Expected half-life for HLA-DR matched grafts was 12 years compared to less than 7 years for HLA-DR mismatched grafts. The effects of matching for HLA-A and -B did not reach statistical significance. In CD regrafts, a two-antigen mismatch for HLA-A or -DR led to a significantly poorer graft survival, but the panel-reactive antibody (PRA) status of the recipient was the most influential factor. In CD renal transplantation, we conclude that organ allocation based on matching for HLA-DR 1-14 is effective and not too difficult to obtain even in centers with a short patient waiting list.