A 72-year-old man with acute lung injury and anti-melanoma differentiation-associated gene 5 antibody: A case report.

Anti-melanoma differentiation-associated gene 5 antibody (anti-MDA-5 Ab) is associated with amyopathic dermatomyositis (DM). These patients are particularly at high-risk for developing acute and rapidly progressive interstitial lung disease (ILD). Given the lack of muscle-related symptoms, along with its sudden onset and rapid clinical progression, the diagnosis of anti-MDA-5 Ab + ILD represents a challenge for clinicians. Even after the diagnosis is established, prognosis remains dismal owing to a hyperinflammatory state, mimicking cytokine storm, commonly refractory to potent immunosuppressive therapy. Hence, we present an elderly African American man who developed acute and rapidly progressive ILD in the setting of positive anti-MDA5 Ab, in whom lung histopathology was consistent with organizing phase of diffuse alveolar damage. Despite receiving combined immunosuppression with corticosteroids, cyclosporine, and cyclophosphamide, he developed irreversible lung injury within a month and was eventually referred for lung transplant evaluation.