Abstract
Purpose::
To evaluate the efficacy of interferon (IFN) alfa-2a for the treatment of long lasting refractory cystoid macular edema (CME) in non-infectious uveitis.
Methods::
Retrospective analysis of a consecutive interventional case series. IFN alfa-2a was administered at an initial dose of 3 or 6 million IU (depending on bodyweight) per day subcutaneously. Afterwards IFN alfa-2a was tapered slowly over six months and discontinued finally if possible. If CME relapsed IFN alfa-2a was reinstituted in a dose of 3 million IU every second day and tapered slowly again in order to evaluate the lowest maintenance dose to keep remission. Control of treatment efficacy was performed by OCT.
Results::
26 eyes of 15 patients (5 male, 10 female; mean age 50.1 years, 19-74 years) with CME (mean duration 64.6 months, 16-132 months) due to non-infectious intermediate (n=12) or posterior (n=3) uveitis were analyzed. Ineffective pre-treatment consisted of systemic steroids and acetazolamide (all patients) and at least one additional immunosuppressive drug (13 patients). IFN alfa-2a showed effective (= complete resorption of CME within four weeks, able to taper IFN) in 17 eyes (65.4%), partially effective (= incomplete resorption of CME, unable to taper IFN) in 5 eyes (19.2%) and not effective (= no response or recurrence of CME due to preexisting or newly developed auto-antibodies against IFN) in 4 eyes (15.4%). In 8 patients (15 eyes) IFN alfa-2a was discontinued after six months in complete remission of CME. One of these patients was lost to follow-up then. In the other 7 patients (13 eyes) IFN alfa-2a had to be reinstituted due to a relapse of CME. However, all 7 patients responded again. During a mean follow-up period of 23.1 months (4 patients 33-36 months, 3 patients 3-14 months) since restart of therapy we were able in all 7 patients to taper IFN alfa-2a to maintenance doses between 3 million IU every third day and 1 million IU every tenth day without a recurrence of CME in any of the 13 eyes. Treatment with IFN alfa-2a was generally well tolerated by the patients. Common side effects such as flu-like symptoms and increased liver enzymes were dose-dependent and did not necessitate cessation of treatment.
Conclusions::
Our data show IFN alfa-2a as an effective and well tolerated treatment for otherwise therapy resistant CME in non-infectious uveitis. Whether and when IFN alfa-2a can be stopped without further relapses of CME is one of the questions that have to be answered in the future.
Keywords: uveitis-clinical/animal model • edema • drug toxicity/drug effects