Leukocytoclastic vasculitis induced by adalimumab biosimilar in an elderly female with rheumatoid arthritis: A case-based review

Background: Adalimumab is one of the most frequently used tumor necrosis factor (TNF) inhibitors con-sidered in the treatment of several autoimmune diseases including rheumatoid arthritis (RA). There have been reports of being adversely associated with the development of lupus and vasculitis. Leukocytoclastic vasculitis (LCV) is the most common form of cutaneous vasculitis that could be associated with different medications including TNF inhibitors.Case presentation: A 64-year-old Iranian female with RA for 11 years presented to the rheumatology clinic, Imam Reza Hospital, Kermanshah University, complaining of erythematous patches, plaques, and erosions on her lower extremities for 20-days. She had been receiving methotrexate (MTX) for 11 years (on 5 mg/week) and adalimumab biosimilar 40 mg every other week for nine months prior to developing the skin lesions. There were no signs of RA activity. The routine laboratory tests and immuno-logical workup including anti-nuclear antibodies (ANA), anti-neutrophil cytoplasmic antibody (ANCA) and serum complements were within normal limits. Abdominopelvic sonography showed no pathologi-cal finding. A skin biopsy confirmed the diagnosis of LCV. Adalimumab and MTX were discontinued and she was started on prednisolone (5 mg/day) and mycophenolate mofetil (2 g/day). Gradual improvement was observed. Similar reported cases of adalimumab-related LCV are presented. Conclusion: Leukocytoclastic vasculitis could be a possible adverse event of TNF inhibitors. Complete improvement occurs after withdrawal of the culprit drug in most cases while corticosteroids and immunosuppressive medications are required in some cases. LCV associated with adalimumab biosimilar should raise the awareness of rheumatologists about this possible complication for appropriate management.(c) 2023 THE AUTHORS. Publishing services by ELSEVIER B.V. on behalf of The Egyptian Society of Rheu-matic Diseases. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).