Histocompatibility testing for keratoplasty in high-risk patients.

Forty-eight consecutive patients at high risk for corneal graft rejection were transplanted with corneas from donors selected on the basis of a negative lymphocyte crossmatch, ABO blood group compatibility, and maximized HLA-A, -B matching. Graft survival in this study group was compared to a retrospective control group of 72 consecutive high-risk transplants performed in patients receiving randomly obtained corneal donors. Demographic parameters, cause of primary disease, and incidence of prior graft rejection were no different between the two groups. Graft survival at one year, calculated by the Kaplan-Meier method, was 78% for the negative crossmatch study group vs 52% in the uncrossmatched control group (P less than 0.05%). All graft failures in the negative crossmatch group were in poorly HLA matched recipients. While patients with evidence of nondonor specific humoral presensitization to HLA antigens experienced earlier graft rejection, overall graft survival was not associated with such nonspecific presensitization. These findings indicate that prospective histocompatibility testing can improve corneal allograft survival for high-risk patients by better identification of appropriate donors.