Post-kala-azar Dermal leishmaniasis: Facing the challenge of eliminating Kala-Azar from South Asia

Abstract

Post-kala-azar dermal leishmaniasis (PKDL) is a cutaneous complication of visceral leishmaniasis (VL) which usually appears after treatment of a VL episode. The incidence of PKDL varies across countries and no up-to-date global estimate is available. Parasitological diagnostic tests show either low sensitivity or are difficult to decentralize in the field (e.g., polymerase chain reaction). Available treatments are long, costly, and frequently toxic. It is believed that PKDL has a multi-factorial and complex origin. It is widely accepted that persons with PKDL harbor Leishmania parasites in the skin and, therefore, act as reservoirs of infection in VL transmission, especially during interepidemic periods. PKDL poses a serious threat to the success of the VL elimination program in South Asia, and requires an immediate and focused strategy from the health authorities in charge of the national programs in India, Nepal, and Bangladesh. Control and research efforts are urgently needed to improve PKDL surveillance and case management in order to reduce delays in diagnosis and treatment and, hence, reduce morbidity and the risk of transmission.