Skin adnexa in leprosy and their role in the dissemination of M. leprae.

Skin biopsies from twenty patients each of tuberculoid, border-line and lepromatous leprosy were studied with a view to find out the presence of bacilli in sweat glands, sebaceous glands, hair follicles and arrector pili muscles and also the pattern of destruction of these tissues by leprous granuloma. M. leprae are found in large numbers in sweat glands, sweat ducts, sebaceous glands, hair follicles and arrector pili muscles. Further in lepromatous leprosy the granulomas mainly surround the skin adnexa which atrophy due to pressure by the granuloma. However in tuberculoid leprosy the inflammatory cells infiltrate the adnexal tissues and destroy them. This study confirms that M. leprae are discharged and disseminated through sweat and sebaceous secretions and therefore infection through skin to skin contact can be one of the common modes of transmission of the disease.