Myopathy in a 61-year-old Hispanic man

A 61-year-old Hispanic man presented to a county hospital for subacute progressive weakness, heliotrope rash and dysphagia. There was initial suspicion for dermatomyositis (DM) given the history; however, the physical exam was not consistent. An MRI followed by a muscle biopsy revealed necrotising autoimmune myositis and anti-3-hydroxy-3-methylglutary-coenzyme A-reductase antibody titers returned positive; the patient was diagnosed with necrotising autoimmune myositis. He was treated with corticosteroids and intravenous immunoglobulin, which resulted in improvement in his weakness and functional status. This case represents a unique instance in which a cardinal feature of DM, the heliotrope rash, prompted an erroneous initial diagnosis. It highlights the necessity of developing abroad differential diagnosis and subsequent thorough investigation into patients presenting with suspected idiopathic immune-mediated myopathies.