Post-COVID-19 Dermatomyositis: A Delayed Reaction That Evades Early Detection.

Dermatomyositis (DM) is a rare autoimmune disease that causes symmetrical and predominantly proximal muscle weakness in the limbs and typical skin lesions. Its prevalence increased during the coronavirus disease-2019 (COVID-19) pandemic. Viral infections may cause autoimmunity and trigger the pathogenesis of myositis. We present the case of a man with a long history of myalgia and muscle weakness, who was initially diagnosed with post-COVID-19 myalgia and subsequently developed progressive muscle weakness. Biochemical and muscle biopsy results confirmed DM. The patient responded favorably to the course of steroid treatment.