Pattern of reactions in leprosy: a clinical appraisal

The term 'reactions' is applied in the present text, to describe the acute episodes, recognized with the different types of leprosy. The incidence of reactions was found to be 9.7% of 1053 cases examined. They were seen in all types of leprosy, but their frequency and severity was marked in lepromatous and borderline cases, and in majority of them, the age ranged from 20-40 years. The precipitating factor(s) could not be established in many; in some dapsone was incriminated, followed by bacterial infection and malnutrition. The exacerbations of the existing lesion(s) either alone or in combination with new lesions (E.N.L.) and E.N.L. lesions alone, were the presenting clinical features. The constitutional symptoms were observed largely in the types other than the tuberculoid. Foot drop and contractures of the fingers were the common sequels of the reactions. An attempt has been made to explain their mechanisms in the light of the recent literature.