[Transplant reaction after keratoplasty for keratoconus. Frequency and risk factors]

Graft rejection is a leading cause of graft failure in keratoplasty for keratoconus.

A consecutive series of 274 keratoplasties performed between 1980 and 1991, for keratoconus was studied, some cases retrospective and others prospectively with postoperative monitoring up to 1993. Excluded from the study were 22 eyes with previous intraocular surgery, simultaneous cataract operations, or eccentric grafts. The mean follow-up was 26.3 months.

Endothelial graft rejection was seen in 19 of the 274 eyes (6.9%), and in 4 of these eyes (1.4%) the graft failed. After 1 year the rejection-free transplant survival rate (Kaplan-Meier survival analysis) was 93.9% ( +/- 1.5% standard error) and after 4 years, 89.3 +/- 2.9%. Younger age of recipient and loosening of the suture were significant risk factors (p < 0.05 for each) for graft rejection episodes. Suture loosening was significantly more frequent in younger recipients (p < 0.001). Recipient's age was not a risk factor in eyes in which suture loosening did not occur.

Younger patients are at greater risk of graft rejection in keratoconus, not only because of their more "active" immune system but also because of a higher risk of suture problems. More attention must be paid to suture problems, especially in younger patients, to decrease the risk of graft rejection in keratoconus patients.