[Miyoshi distal myopathy: specific signs and incidence].
We report 21 French patients (12 males and 9 females), presenting a distal myopathy of Miyoshi type. The main clinical features of these patients were 1) onset in late adolescence or early adulthood (mean age: 20.3 years), 2) early and predominant involvement of the posterior compartment muscles of legs, 3) marked elevation of serum CK (from 10 to 50 times the normal value), 4) dystrophic features with a necrotic regeneration pattern without vacuole in muscle biopsy. All cases were sporadic and a consanguinity of parents was found in five cases. The clinical course was relatively mild: twelve patients could walk without aid; However four patients were severely disabled. Four patients were initially considered as having polymyositis; corticosteroids and immunosuppressive drugs were always inefficient. A genetic linkage to chromosome 2 was ascertained in five cases. In our experience the Miyoshi distal myopathy is the most common form of distal myopathy, particularly in young patients.
Eymard
B
B
Institut de Myologie, Fédération de Neurologie Mazarin, INSERM U 523, Hôpital de la Salpêtrière, Paris.
Laforêt
P
P
Tomé
F M
FM
Collin
H
H
Leroy
J P
JP
Hauw
J J
JJ
Richard
I
I
Beckmann
J
J
Fardeau
M
M
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007866:Leg; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology; D009136:Muscular Dystrophies / Q000175:diagnosis* / Q000453:epidemiology* / Q000503:physiopathology; D016138:Walking