Incidence and pattern of demyelinating disease in India

Abstract

In one of the major neurological centres in India, there were 69 patients among 7520 neurological admissions seen between 1965 and 1970, in whom a diagnosis of primary demyelinating disease was considered. Of these, 17 were classified as cases of probable multiple sclerosis and 52 as “possible” cases. The majority of the “possible” cases were patients with localized myelopathies of both acute and chronic varieties. Brain stem demyelinating disease and retrobulbar neuritis formed the rest of the cases in this group. The clinical features and the course of the 17 cases of multiple sclerosis resembled those observed in the Western hemisphere. However, the incidence was low, 0.22%, which is comparable to the incidence of multiple sclerosis in Korea, Japan and Indonesia. The most striking feature was the relatively high incidence of demyelinating disease other than typical multiple sclerosis. These cases formed two-thirds of the total number. Neuromyelitis optica was not observed in this series though localized myelopathies and retrobulbar neuritis occurred separately. It may be worthwhile examining in the future the aetiological factors responsible for the higher incidence of demyelinating diseases other than typical multiple sclerosis in India, with particular reference to the rôle of tropical infections and nutritional disorders.