The significance of the IgG anti-B-cell crossmatch on renal transplant outcome.

Transplantation in the presence of anti-class I antibodies usually results in allograft hyperacute rejection. Because of the perception of its uncertain clinical significance, B-cell crossmatch which identifies presence of anti-class II antibodies is not universally performed. In a retrospective study, the clinical course of renal transplant recipients with IgG anti-B-cell antibodies was analyzed and compared with case control patients transplanted contemporaneously, matched demographically and immunologically. The incidence of hyperacute, acute, and chronic rejection as well as graft loss were significantly higher in the group with anti-IgG B-cell antibodies compared to the control. We conclude that anti-B-cell IgG antibodies are harmful to allografts with a spectrum of events that include hyperacute, acute, vascular and chronic rejection. While allografts were successful in some patients, our experience suggests caution whenever anti-donor B-cell IgG is present. If transplants are performed, then more potent immunosuppression should be used.