Systemic Immunosuppression in Ocular Surface Stem Cell Transplantation

Abstract

To describe the systemic immunosuppression protocol used at the Cincinnati Eye Institute and University of Cincinnati, and to evaluate the success, tolerability, and side effects of systemic immunosuppression in patients undergoing ocular surface stem cell transplantation (OSST). Retrospective study of all patients who had OSST from 1997 to 2007 and received follow-up for systemic immunosuppression at the Cincinnati Eye Institute. Patients were analyzed for demographics, systemic immunosuppression exposure, ocular surface stability, efficacy, and toxicity variables. A total of 225 eyes from 136 patients with a mean age of 43.6 years (range, 8.9-80.6 years) underwent OSST with systemic immunosuppression. The most common systemic immunosuppression regimen consisted of tacrolimus, mycophenolate mofetil, and a short course (1-3 months) of prednisone (102/136 patients, 75%). Prophylactic valganciclovir and trimethoprim/sulfamethoxazole (dapsone if sulfa allergy was present) were also used. Mean duration of immunosuppression was 42.1 months (range, 3.6-128 months) and mean follow-up time after OSST was 53.9 months (range, 3.6-147.3 months). At the patients' final follow-up visit, 105/136 patients (77.2%) had a stable ocular surface. There were 3 severe adverse events in 2 patients (1.5%) and 21 minor adverse events in 19 patients (14.0%). Of the 21 patients with adverse events, 10 (47.6%) had systemic comorbidities at initial presentation. The prevention of graft rejection with the use of systemic immunosuppression after OSST is crucial and should be approached with the same rigor as in solid organ transplantation. With appropriate long-term monitoring by the cornea specialist and transplant physician, the risk of irreversible toxicity at current dosages of systemic immunosuppression in this population is minimal.