AUTHOR=Żukowicz-Wyrwa Wioletta Katarzyna , Markiet Karolina , Damps Tatsiana , Ciarka Aleksandra , Karaszewski Bartosz , Nowicki Roman TITLE=Case Report: Severe psoriasis skin lesions following ofatumumab treatment for multiple sclerosis JOURNAL=Frontiers in Immunology VOLUME=Volume 16 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2025.1595947 DOI=10.3389/fimmu.2025.1595947 ISSN=1664-3224 ABSTRACT=The article explores a case study of a patient diagnosed with relapsing-remitting multiple sclerosis (RRMS) who, while receiving treatment with the anti-CD20 monoclonal antibody ofatumumab, developed psoriatic skin lesions. Initially, sharply demarcated, scaly, erythematous lesions were observed only in the anogenital area. After several weeks, additional lesions appeared on the ear lobes, scalp, and lower legs following subsequent administrations of ofatumumab. A comprehensive differential diagnosis of the skin lesions was performed, which included consideration of autoimmune chronic diseases, infectious disease manifestations, and skin carcinomas. Biopsies of the lesions were obtained and underwent histopathological examination. Based on the clinical presentation and further investigations, it was concluded that the skin lesions were an atypical adverse reaction to ofatumumab, manifesting as psoriasis. In addition to presenting this case, we analyze the spectrum of common adverse reactions associated with ofatumumab, as well as the occurrence of psoriasis following other anti-CD20 therapies. To the best of our knowledge, this is a rare, documented instance of psoriasis occurring in a patient receiving ofatumumab for the treatment of multiple sclerosis.