Effectiveness of Cyclosporine A and HLA-Matching in the Prevention of Immune Reactions and Graft Failure in High-Risk Keratoplasties

Abstract

Purpose: : Postoperative immunosuppression is a measure to prevent graft failure in high risk keratoplasty. Although cyclosporine A is frequently used, it is not yet considered standard of care. In this retrospective study the long-term effectiveness of systemic cyclosporine A after high risk keratoplasties was analysed.

Methods: : From January 2001 to January 2009 a total of 70 high risk keratoplasties treated with postoperative CSA treatment were analysed retrospectively according to the number of risk factors, the degree of preoperative corneal vascularization and tissue matching of the graft. Endpoints included immunological graft rejection, graft failure, and the development of visual acuity.

Results: : Clear graft survival after 1 year was noted in 89.5% of the grafts, after 3 years in 56.4%. Overall, there was a trend towards an improvement of visual acuity (41 of 62 patients). Patients with expected postoperative surface problems showed a significant increase of graft failure (p = 0.014) and a worse functional outcome. In cases of matched grafts in only 2 of 13 cases graft failure occurred. Six out of 26 graft failures were failures from rejection (23.1%). After 1 year 84.4% of the grafts were rejection-free, after 3 years 71.1%. Patients with 3-4 quadrants of corneal vascularization showed higher rates of graft rejection than patients with avascular corneas. In 9 of 63 patients (14.3%) side effects of the CSA treatment were noted. In 2 cases treatment was terminated because of serious adverse events.

Conclusions: : Vascularization is the main risk factor for immune reactions independent of other risk factors. Especially in these vascularized corneas CSA seems to be highly efficient in the prevention of immune reactions, but not of graft failures. Thus, graft failure of other causes than graft rejection still remains a problem despite CSA treatment and is a main reason for a low functional outcome. The risk for graft failure depends on the preoperative diagnosis and pre-existing other risk factors. HLA matching seems to be an effective additional measure to CSA treatment for preventing graft failure in high risk keratoplasties.

Keywords: cornea: clinical science • immunomodulation/immunoregulation • neovascularization