Cardiac involvement in a case of juvenile dermatomyositis with positive anti‐melanoma differentiation associated protein 5 antibody

Abstract

Juvenile dermatomyositis (JDM) is an autoimmune disease characterized by muscle weakness and specific skin lesions, as well as non‐muscular involvement such as interstitial lung disease (ILD), cardiac involvement and arthritis. Anti‐melanoma differentiation‐associated protein 5 (anti‐MDA5)‐positive JDM patients are typically characterized by the presence of skin ulcers and rapidly progressing ILD (RP‐ILD). Although cardiac involvement is not an expected involvement in anti‐MDA5‐positive JDM cases, it is significant because it can be fatal. In this report, an anti‐MDA5 myositis‐specific autoantibody‐positive JDM case referred with the diagnosis of psoriatic arthritis in whom cardiomyopathy and arrhythmia were detected in follow‐up is presented. Since cardiac involvement is associated with mortality, it would be useful to follow up anti‐MDA5 positive patients for cardiac involvement in addition to lung involvement. Tofacitinib is a promising treatment option in treatment‐resistant JDM.