An unusual presentation of scleromyxedema as inflammatory myopathy

Scleromyxedema is a rare cutaneous mucinosis with frequent extracutaneous manifestations. Myopathy in scleromyxedema is a poorly recognized syndrome among neurologists and can mimic idiopathic and connective tissue disease-associated inflammatory myopathy. Diagnosis is suspected by the characterization of the skin lesions and clinched by skin and muscle biopsies. Here, we report a patient with scleromyxedema and myopathy with the characteristic histopathological feature of mucin deposition in skin biopsy. Her muscle biopsy showed a picture consistent with scleromyxedema myopathy with vacuolar and inflammatory changes. The association with paraproteinemia, propensity to life-threatening central nervous system disease and good response to intravenous immunoglobulin necessitate the accurate diagnosis of this condition.