Renal allograft survival in patients with positive B cell crossmatch to their donor.

B cell crossmatches were performed at cold (4 C) and warm (22 C and 37 C) temperatures on 193 renal allograft recipients with negative T cell crossmatches to their donor; 152 of the patients were also tested for autoantibody to autologous B cells. Fifty-six (29%) had a positive B cell crossmatch (21 cold, 35 warm); 14 were autoantibody positive, 23 autoantibody negative, and 19 were not tested for autoantibody. There were no differences in HLA-A, B, C, or DR antigen disparity between the B cell positive (14, 0 DR mismatch; 25, 1 DR mismatch; 9, 0 DR mismatch) and the B cell negative group (40, 0 DR mismatch; 57, 1 DR mismatch; 13, 2 DR mismatch). Similarly, age, diabetic status, and number and type of pretransplant blood transfusions were comparable between B cell positive and negative groups. Although there were no hyperacute rejections, 2-year actuarial graft survival was significantly lower in the B cell positive group, regardless of donor source, graft number, or temperature of reaction. Patients with a positive B cell crossmatch, presumably due to demonstrable autoantibody, may have better graft survival rates than patients with a positive B cell crossmatch and no autoantibody.