Coexistence of Dermatomyositis and Alopecia Areata: Insight into Pathogenesis

A 9-year-old girl with juvenile dermatomyositis (DM) and alopecia areata (AA) presented with muscle weakness and a heliotrope rash. She had a history of progressive nonscarring baldness. Diagnostic tests confirmed DM, and treatment with methotrexate and prednisolone led to significant improvement in both muscle power and hair regrowth within a month. The coexistence of DM and AA in this patient suggested a potential etiological link between the two immune-mediated diseases, possibly involving interferon-α and major histocompatibility complex (MHC) class I molecules. This rare association highlighted the need for further research into the shared pathogenesis of these conditions.