A Case of Nemaline Myopathy

ABSTRACT

Childhood onset nemaline myopathy, first described in 1963 by Shy, et al and Conen, et al, is rare congenital myopathy, characterized by nonprogressive or slowly progressive muscle weakness associated with rod-like structures in muscle fibers, often with dysmorphic features. This myopathy was confirmed by muscle biopsy. The light microscopic features noted generally small round fibers that showed variation in size and occasional internal nuclei and characteristic rod bodies that could be demonstrated in the longitudinal sections stained with modified Gomori trichrome stain. Electromicroscopically there were accumulations of numerous irregular electron dense materials scattered between the myofibrils, particularly under the sarcolemma and enlargement and streamimg of the Z disk. We report a case of childhood onset nemaline myopathy in Korea in a 7 year- old boy who had nonprogressive muscle weakness of the limbs with a waddling gait.