A Case of Acute Viral Myositis

Diffuse myalgia is common in transient systemic viral infections but overt myositis, with weakness and signs of muscle inflammation, rarely accompanies viral infection in chidren. We describe a 8-year-old boy with severe myalgia and tenderness in both lower extremities, whose unusual skeletal muscle uptake on Technetium-methylene diphosphate bone scan helped to diagnosis of myositis. Clinical course, muscle-derived enzyme studies(AST, ALT, LD, CK), electromyogram findings, histopathologic findings obtained from left gastrocnemius muscle biopsy and serologic studies for enteroviral antibodies (enterovirus type 71 and Coxsackie B4 neutralization antibody titer 1:128 respectively) were all compatible with acute viral myositis.