Anti-MDA-5 Dermatomyositis With Development of Drug-Mediated Necrolytic Skin Lesions

A 59-year-old male presented with 1 month of progressive dyspnea, 30-lb weight loss, and skin changes on the digits of the hands. In the 4 weeks prior to admission, he was admitted and treated twice for pneumonia at another hospital and received intravenous (IV) vancomycin, ceftriaxone, and azithromycin for a total of 10 days. After admission, he underwent computed tomography imaging of chest, which revealed findings suggestive of interstitial lung disease but given the fact that infection was not ruled out, empiric antibiotics were initiated. The skin lesions on the fingers were felt to be consistent with Gottron's papules, and his overall constellation of findings were felt to be consistent with dermatomyositis (DM). Over the following 3 days, he developed diffuse, violaceous skin lesions, elevation of liver transaminases, and severe thrombocytopenia. The skin lesions progressed to epidermal necrosis. He developed erosions of the oral mucosa and scrotum. Before skin biopsy results were finalized, IV immunoglobulin and IV dexamethasone were started empirically for suspected DM and immune-mediated thrombocytopenia. His laboratory abnormalities normalized within a week. Biopsy results of the skin were consistent with Stevens-Johnson syndrome (SJS). Autoantibody test for anti-MDA5 were positive, confirming a diagnosis of anti-MDA5 associated DM. Subsequent development of SJS was likely due to antibiotic exposure in the preceding month. Simultaneous development of anti-MDA5 DM and SJS raises the question of a link between the 2 conditions. To our knowledge, this is the first reported association of these 2 conditions reported in the literature.