First Reported Case of Ocrelizumab-Associated Leukocytoclastic Vasculitis in Primary Progressive Multiple Sclerosis:...

Leukocytoclastic vasculitis (LCV) is a small vessel vasculitis primarily affecting the skin, and its association with specific drugs is not widely documented. This case study explores the occurrence of LCV following the initiation of ocrelizumab, a monoclonal antibody used in the treatment of primary progressive multiple sclerosis (PPMS).

A 49-year-old Iranian female with PPMS developed lower limb edema and diffuse palpable purpura 1 week after starting ocrelizumab therapy. Skin biopsy confirmed LCV, showing vessel wall destruction, neutrophil infiltration, and fibrinoid necrosis. Laboratory tests revealed elevated inflammatory markers, including ESR 1 h: 52 and CRP: 52.8, supporting the diagnosis. The patient's symptoms improved after a course of intravenous methylprednisolone, and ocrelizumab was resumed without recurrence of skin lesions. This case highlights the need for vigilance in detecting drug-related vasculitis in ocrelizumab-treated patients.

This case is the first reported instance of LCV associated with ocrelizumab in the treatment of multiple sclerosis. It underscores the need for awareness of potential drug-induced vasculitis in patients undergoing new or modified treatments and contributes to the growing understanding of adverse effects associated with ocrelizumab.