Lee, Haur YuehHaur YuehLeePelivani, NedzmidinNedzmidinPelivaniBeltraminelli, HelmutHelmutBeltraminelliHegyi, IvanIvanHegyiYawalkar, NikhilNikhilYawalkarBorradori, LucaLucaBorradori2024-10-112024-10-112011https://boris-portal.unibe.ch/handle/20.500.12422/77500Amicrobial pustulosis of the folds (APF) is a recently described entity characterized by relapsing pustular lesions predominantly involving the cutaneous flexures and scalp. This disease typically occurs in association with systemic lupus erythematosus and a variety of other autoimmune diseases. We here describe an APF-like pustular eruption predominantly affecting the scalp, face and trunk, occurring during long-term infliximab treatment for Crohn's disease. Immunohistochemical staining of skin biopsy specimens for myxovirus resistance protein A, a marker for type 1 interferon-inducible proteins, showed increased staining in the epidermis and dermal mononuclear inflammatory infiltrate. Our observation further extends the spectrum of cutaneous adverse reactions potentially related to anti-tumor necrosis factor-α, the clinical context in which APF can occur as well as its clinical presentations.enarticle10.48350/70452175788200029454420000410.1159/000329428