Predisposing factors in corneal graft rejection.

During a period of 12 years, 390 patients were treated with perforating keratoplasty and given regular annual follow-ups. Of these, 357 records were evaluated, and there was a 20% incidence of immunoreactions. The transplants were assessed according to four criteria and subdivided into a low-risk and a high-risk group. For high-risk patients, the relative risk of developing an immunoreaction was 2.9 times greater with subdivision according to the preoperative diagnosis, 2.1 times greater with a transplant diameter of 7.5 mm or more, 2.6 times greater with compatibility between fewer than two HLA-B or -DR antigens of the donor and recipient, and 4.2 times greater with blood or fibrin in the anterior chamber on the first postoperative day. There was a linear relation between the frequency of being placed into the less-favorable-prognosis group and the occurrence of an immunoreaction.