Interferon-Induced Retinopathy

Interferons were discovered in 1957 by Issacs and Lindenmann during investigations into virus interference and have since become essential in treating hepatitis C, cancers, and immune-mediated disorders such as multiple sclerosis. Although interferon therapy is considered effective, it has the potential to induce adverse effects on different systems within the body. A significant adverse effect associated with interferon is retinopathy, identified by flame-shaped retinal hemorrhages, cotton wool spots, and macular edema observed during funduscopic examination. Interferon-induced retinopathy is a potential complication of interferon therapy that may cause temporary and asymptomatic effects. However, due to the risk of vision loss, it is important to take a vigilant approach to prevention and early detection. In 1986, the Food and Drug Administration (FDA) approved the use of interferon-α-2a and interferon-α-2b for treating hairy cell leukemia. Since then, the application of interferons has broadened to encompass a variety of conditions. Despite their efficacy, interferon-α treatment may lead to systemic toxicity affecting the central nervous, gastrointestinal, endocrine, cardiovascular, renal, and musculoskeletal systems. The first reported case of ocular toxicity associated with interferon therapy was obtained from Ikebe and associates in 1990. They documented a 39-year-old patient who developed retinal hemorrhages and cotton wool spots after receiving intravenous interferon (see Cotton Wool Spots). Determining whether to continue interferon treatment or opt for a dose reduction can be challenging due to the various manifestations that may arise. These manifestations may be caused by the occlusion of retinal capillaries or other ischemic etiologies due to immune complex deposition. Although less likely, severe adverse effects such as retinal artery and vein occlusion and optic neuritis are possible.