Myopathy With Storage Of Glycoproteins And Glycosaminoglycans

Ionasescu et al. (1984) described mother and daughter, aged 28 and 5 years, respectively, who showed mild to moderate weakness and atrophy of facial and shoulder muscles with congenital onset and minimal progression. Serum creatine kinase was elevated in the child. Muscle biopsy showed normal light-microscopic and histochemical findings, but scattered sarcoplasmic vacuoles with storage of granular material on electron microscopy. Granular material was identified also in fibroblasts. Cultured fibroblasts were shown to have excessive storage of glycosaminoglycans and glycoproteins. Cultured fibroblasts also showed a 1.7-3.4 times increased uptake of labeled glucosamine as compared with controls; the rate of turnover of the radioisotope was normal. The clinical picture was that of mild facioscapulohumeral muscular dystrophy with congenital onset and minimal progression. The authors cited 3 other reports, but all were sporadic cases which showed clinical features different from those in this mother and daughter (Karpati et al., 1969; Radu et al., 1974).