Congenital myopathy with cytoplasmic bodies.

Since early infancy, a 15-year-old girl had suffered from an apparently static neuromuscular disorder that chiefly afflicted her proximal muscles but did not spare her distal ones. Her CPK values had repeatedly been mildly elevated and her electromyogram had been considered "myopathic". There were no similar neuromuscular disorders in the family. Quadriceps muscle biopsy showed a type I myofiber predominance of 96%, this girl's muscle disease represented "congenital myopathy with cytoplasmic bodies" as cytoplasmic bodies were recently reported in other sporadic and hereditary neuromuscular disorders of unknown origin.