Distal Myopathy of Miyoshi Type: 1 Case

J Korean Neurol Assoc > Volume 17(6); 1999 > Article

Journal of the Korean Neurological Association 1999;17(6): 916-919.

임상적으로 미요시형의 원위부 근육병증으로 진단된 1예

홍석찬, 김병준 ·이은아 ·서연림*

성균관대학교 의과대학 삼성서울병원 신경과,진단병리과*

Distal Myopathy of Miyoshi Type: 1 Case

Seok Chan Hong, M.D., Byoung Jun Kim, M.D., Eun A Lee, M.D., Yeon-Lim Suh, M.D.*

Department of Neurology, Diagnostic Pathology * Samsung Medical Center, School of Medicine, Sungkyunkwan University

Abstract

Miyoshi myopathy (MM) is a type of distal myopathy that is characterized by an early adult onset and a prominent involvement of the gastrocnemius muscles. Weakness usually appears between 15 and 30 years of age starting in the posterior compartment of the legs. Creatine kinase (CK) values are characteristically elevated to levels 10 to 100 fold above normal range. Here we report one patient who was diagnosed as MM. She developed a motor weakness in her early thirties. There was an early and predominant involvement of the gastrocnemius muscles. Creatine kinase activity was elevated 10 to 15 fold above normal range. Electromyography revealed fibrillations, positive sharp waves, and a myopathic pattern of motor unit potentials, particularly in the distal muscles of the lower limbs. Myopathic features without vacuoles were seen in the vastus lateralis muscle. This is the first case report of MM in Korea, which should be considered in the differential diagnosis of slowly progressive weakness of distal legs. J Korean Neurol Assoc 17(6):916~919, 1999 Key Words : Distal myopathy, Miyoshi myopathy