Muscle diseases in Singapore.

This study aims to establish the pattern of muscle diseases in Singapore. Two hundred consecutive muscle biopsies collected prospectively over a period of 7 yr (1978-1984) were studied using light microscopy, histochemistry and electron microscopy. Muscle diseases were not uncommon. There was no racial predilection. The common muscle diseases were polymyositis, spinal muscular atrophies and muscular dystrophies. Less common ones included congenital myopathies and storage diseases due to disorders of glycogen and lipid metabolism. Other muscle diseases were uncommon. Polymyositis was the commonest muscular disorder in adults and spinal muscular atrophy in childhood. This finding is encouraging as polymyositis is a treatable condition. The common occurrence of spinal muscular atrophies in this country was not fully appreciated. They were often misdiagnosed clinically as muscular dystrophies. It is hoped that this finding will result in greater awareness of this condition which is necessary for proper genetic counselling and management.