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A case of congenital neuromuscular disease with uniform type 1 fiber
Sang-Jun Na1, Seong-Woong Kang, Kee-Oog Lee
1Department of Neurology, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
Abstract:
Congenital neuromuscular disease with uniform type 1 fiber (CNMDU1) is a rare but distinct form of nonprogressive, congenital myopathy. CMNDU1 is characterized by a type 1 muscle fiber content of more than 99%. This condition has only been previously described in a few reports. The authors report an 11-year-old girl who exhibited delayed developmental milestones, proximal muscle weakness, and bilateral ptosis. Her serum creatine kinase level was normal but an electromyographic study showed myopathic changes. A biopsy specimen from the left deltoid muscle revealed a uniformity of type 1 fibers (greater than 99%) with a moderate variation in fiber size. This is the first case of CNMDU1 reported in Korea.
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