[Congenital centronuclear myopathy. Two morphological variants in one family (author's transl)].

This report deals with a family in which the mother and her two daughters suffer from a congenital, slowly progressive neuromuscular disease. Histological, histochemical and ultrastructural observations of the mother's muscle biopsy reveal the characteristics of the centronuclear myopathy. In this case central nuclei and pericentronuclear abnormalities of muscle fibers are found in almost all fibers. Biopsies obtained of the two daughters show alterations especially of type I-fibers, which often are smaller than normal. The presence of these two forms of centronuclear myopathy in one family indicates that these may be only different morphological types of states of one illness. Additionally, other structural findings (rod bodies, core like regions) emphasize the similarities with other congenital slowly progressive myopathies (nemaline myopathy, central core disease).