Rinsho Shinkeigaku (Clinical Neurology)

Case Report

A case of LGMD2A (Calpainopathy) clinically presenting as Miyoshi distal myopathy

Toshihiko Shirafuji, M.D.1), Yoshihisa Otsuka, M.D.1), Hiroshi Kobessho, M.D.1), Narihiro Minami, Ph.D2), Yukiko Hayashi, M.D.3), Ichizo Nishino, M.D.3) and Fumio Kanda, M.D.1)

1)Division of Neurology, Department of Internal Medicine, Kobe University Graduate School of Medicine
2)Department of Laboratory Medicine, Musashi Hospital, National Center of Neurology and Psychiatry
3)Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP)

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.
Full Text of this Article in Japanese PDF (524K)

(CLINICA NEUROL, 48: 651|655, 2008)
key words: Calpain 3 gene mutation, Miyoshi distal myopathy, LGMD2A gene analysis

(Received: 25-Apr-08)