Leishmaniasis is a protozoan disease whose diverse clinical manifestations are dependent both on the infecting species of Leishmania and on the immune response of the host. Transmission of the disease occurs through the bite of a sand fly infected with Leishmania parasites. Infection may be restricted to the skin in cutaneous leishmaniasis, limited to the mucous membranes in mucosal leishmaniasis, or spread throughout the reticuloendothelial system in visceral leishmaniasis or kala azar. Three rare clinical variants of cutaneous leishmaniasis include diffuse cutaneous leishmaniasis, leishmaniasis recidivans, and post-kala-azar dermal leishmaniasis.