[Case of LGMD2A (calpainopathy) clinically presenting as Miyoshi distal myopathy].
We reported a 23-year-old woman with distal myopathy and highly elevated serum creatine kinase (CK) caused by calpainopathy. Although muscle weakness was not evident, a muscle CT scan revealed replacement by adipose tissue in the medial head of the gastrocnemius. The gluteus maximus and biceps femoris were also affected to a lesser degree, but the lateral head of the gastrocnemius was preserved. A histological study of a biopsied specimen of the biceps brachii revealed obvious variation in fiber size and a few necrotic or regenerating fibers. Rimmed vacuoles or lobulated fibers were absent in vacuoles. Although the clinical features suggested Miyoshi's distal myopathy, gene analysis of calpain 3 revealed a c.802-9G > A mutation in intron 5 and a c.1319G > A (p.Arg440Gln) in exon 10. Mini-multiplex Western Blotting (MMW) of the patient's muscle showed no band in calpain 3 (p94) and calpain 3 30 kDa fragments and immunoblotting did not reveal any dysferlin abnormalities. Calpainopathy should be also considered in patients with clinical manifestations of Miyoshi distal myopathy.
Shirafuji
Toshihiko
T
Division of Neurology, Department of Internal Medicine, Kobe University Graduate School of Medicine.
Otsuka
Yoshihisa
Y
Kobessho
Hiroshi
H
Minami
Narihiro
N
Hayashi
Yukiko
Y
Nishino
Ichizo
I
Kanda
Fumio
F
D002154:Calpain / Q000235:genetics*; D003402:Creatine Kinase / Q000097:blood; D003937:Diagnosis, Differential; D049310:Distal Myopathies; D005260:Female; D006801:Humans; D009124:Muscle Proteins / Q000235:genetics*; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000473:pathology; D049288:Muscular Dystrophies, Limb-Girdle / Q000175:diagnosis* / Q000235:genetics*; D009154:Mutation; D014057:Tomography, X-Ray Computed; D055815:Young Adult
D009124:Muscle Proteins; D003402:Creatine Kinase; C105884:CAPN3 protein, human; D002154:Calpain