Acta Reumatológica Portuguesa
Rituximab in the treatment of anti-MDA5 dermatomyositis-associated interstitial lung disease: a case-based literature review
Interstitial lung disease (ILD) occurs with Idiopathic Inflammatory Myopathy (IIM) as a life-threating complication and is considered the most important prognostic determinant in this disease group. The antibody anti-melanoma differentiation–associated gene 5 (anti-MDA5) is associated to rapidly progressive ILD and poor overall survival. Rituximab (RTX) is becoming a drug of choice in management of refractory IIM-ILDs and rapidly progressive ILDs, despite its low level of evidence. We report the case of a 49-year-old man with new-onset clinically amyopathic dermatomyositis (CADM) with severe respiratory symptoms and mixed radiologic pattern of non-specific interstitial and organizing pneumonia, refractory to high dose corticosteroids and intravenous immunoglobulin and oxygen dependent. He was started on RTX 375mg/m2/week of which he completed 4 perfusions, with significant clinical improvement, and has been on maintenance to date with the rheumatology RTX standard protocol with no need for oxygen supplementation. RTX may represent a rescue therapy for patients with severe anti-MDA5-related CADM-ILD refractory to conventional immunotherapies. We identified reports of a total of 12 patients treated with RTX. Infection was the only reported adverse event (25%). Respiratory improvement (defined by symptoms, imaging or PFTs) was observed in 75% of patients, with 2 (17%) having achieved clinical remission. A total of three deaths occurred (25%), all resulting from ILD progression despite treatment. No therapeutic protocol with RTX seems to be more efficient nor associated with more adverse events than the others. Comparative studies are necessary.
Joana Nascimento, Catarina Tenazinha, Raquel Campanilho-Marques, Inês Cordeiro, Sara Salgado. Rituximab in the treatment of anti-MDA5 dermatomyositis-associated interstitial lung disease: a case-based literature review. ARP Rheumatology, Vol 1, nº2 2022:168-173. PMID: 35810375