Epidemiology and risk factors for corneal graft rejection

Abstract

Objective: The aim of this study was to evaluate the frequency and main risk factors for corneal graft rejection.

Patients and methods: This retrospective study included 285 eyes in 256 patients who underwent a penetrating keratoplasty (KPT) from January 1995 to December 2004. The minimum follow-up was 12 months to evaluate graft evolution. Except for complications, the follow-up was weekly, then monthly for 6 months, and ultimately quarterly during the first year. Thereafter the follow-up was performed semi-annually. Patients were informed about the functional signs for which they have to urgently consult.

Results: Immunologic rejection of the corneal graft occurred in 128 KPT in 112 patients (rejection frequency = 41%). The identified main risk factors were new vascularization of the recipient cornea over 2 or more quadrants, corneal opacity due to an infectious origin, posttraumatic corneal opacity or congenital glaucoma, graft diameter >8 mm, and therapeutic KPT.

Conclusions: Rejection of the corneal graft is the primary cause of KPT failure. One out of 2 graft failures was due to rejection. Two criteria are unanimously recognized as risk factors for rejection: neovascularization of recipient cornea and antecedents of corneal rejection. The rejection must be treated early to not endanger graft success, which imposes a close follow-up for grafted patients.