Transaminitis as the Initial Presentation of Anti-MDA5 Positive Juvenile Dermatomyositis: A Case Report

Anti-MDA5 positive JDM is associated with rapidly progressive ILD, causing high morbidity and mortality. We present a case of a child with anti-MDA5 positive JDM who presented with transaminitis and elevated CPK, leading to an original diagnosis of infective myositis of multiple sites. Seven days after the initial encounter, the patient returned with classic JDM symptoms of skin erosions, heliotrope rash, and Gottron’s papules, leading to a diagnosis of anti-MDA5 positive JDM with ILD. Why should an emergency physician be aware of this? Liver dysfunction is a growing concern among anti-MDA5 positive JDM and may be associated with risk factors that lead to poorer prognosis. Because this patient did not originally present with classic skin findings of JDM, diagnosis and treatment of her condition was delayed. Early identification of anti-MDA5 positive JDM is crucial to prevent rapidly progressive ILD.