[Familial form of centronuclear myopathy in the adult]

Two adult cases of centronuclear myopathy are described in a family from French Guyana. One of them, aged 23, has a slight weakness despite hypertrophic muscles. A typical picture of centronuclear myopathy was seen on muscle biopsy with atrophy of type I fibers and hypertrophy of II A fibers. His uncle, aged 53, had a progressive weakness of the lower limbs for the last 25 years, with also a pattern of centronuclear myopathy, but with more dystrophic features and atrophy of both type I and II A fibers. The mode of inheritance is dominant. These two cases are compared with the previously published reports. The pathogenesis of centronuclear myopathy is discussed.