Effect of interferon α2a in cystoid macular edema due to intraocular infection

Purpose: Cystoid macular edema (CME) is a severe complication and a major cause of visual loss in patients with intraocular infection. In this type of CME, therapeutic strategies remain controversial. We aimed to investigate the efficacy and tolerability of interferon (IFN)-alpha 2a in cystoid macular edema caused by intraocular infection. Methods: In this retrospective, noncomparative, interventional case series, 5 patients (6 eyes) who were diagnosed with intraocular infection with chronic CME were included. Interferon-alpha 2a (3 million units 3 times a week) was administered subcutaneously. Clinical observations were recorded before and after treatment. Results: The average duration of CME before treatment with IFN-alpha was 26 months. According to the preset criteria, IFN-alpha 2a therapy was shown to be effective in 2 patients (3 eyes), effective dose-dependent in 2 patients, and partly effective in 1 patient, and was well-tolerated in 4 patients. The most common side effect was flu-like symptoms. Conclusions: Interferon alpha-2a may be an effective alternative treatment for CME due to intraocular infection that is resistant to other treatment. Studies with larger sample sizes are required to confirm this conclusion.