Abstract
Few comprehensive epidemiological studies of the prevalence of muscle diseases have been undertaken, and none has been carried out in our locality. The present cross-sectional study was conducted in Assiut Governorate (Upper Egypt) to estimate the prevalence of different types of primary muscular disorder in 1997. The study involved 52,203 subjects, 15,617 (30%) from the rural community and 36,586 (70%) from the urban community. Patients were identified from a door-to-door survey, and all were subjected to a full clinical examination, with confirmation of the diagnosis through electrophysiological, and biochemical investigations. Histopathological studies were performed for the classification of muscular dystrophies. Forty patients with muscular disorders were identified, with a point prevalence of 76.6 per 100,000 in the total community with no significant differences between the rural and urban communities. The creatine kinase level was abnormally high (>225 IU/l) in 80% of the cases, increased in all patients with muscular dystrophy or myositis, in 88.8% of patients with systemic myopathy and 66.6% of patients with myotonia. None of the cases of myasthenia showed an increase in the creatine kinase level. The lifetime prevalence per 100,000 was 26.8 for muscular dystrophy, 11.49 for myotonia, 11.49 for myositis, 17.24 for systemic myopathy and 9.57 for myasthenia.