Cutaneous Necrosis After Injection of Polyethylene Glycol–Modified Interferon Alfa

In 2005, a study by Dalmau et al. reported that five patients receiving weekly subcutaneous injections of pegylated interferon alfa-2b developed cutaneous necrosis at the injection sites. These patients were being treated for chronic hepatitis C or chronic myelocytic leukemia. The resulting ulcers healed slowly with local therapy, but some patients required dose reductions or discontinuation of treatment. Histopathologic examination indicated epidermal necrosis, acute dermal inflammation, tissue eosinophilia, and focal vasculitis. Thrombosis in one biopsy suggested that small vessel endothelial alterations might contribute to the necrosis. The study emphasized the need for awareness of this complication and the potential necessity for changing injection sites and adjusting dosages. It was noted that while injection site pain is rare, skin reactions occur in up to 75% of patients, and in cases of livedoid necrosis, surgical treatment may be needed. Continuation of treatment at alternative sites is possible, but persistent skin issues may require stopping the drug. Prevention strategies include proper self-injection training, rotating injection sites, and monitoring for persistent erythema, with topical care and hydrocolloid bandages being effective treatments.