Parasites in Sudanese cutaneous and mucosal leishmaniasis

Abstract

Amastigotes from 18 Sudanese cases of visceral, cutaneous and mucosal leishmaniasis were measured, their immunodiffusion reactions tested and their infectivity examined in mice and hamsters. All 18 strains were serologically identical. Their amastigotes varied in size but the mucosal parasites more closely resembled the visceral than the cutaneous parasites, which were also the largest. The cutaneous parasites behaved like the Leishmania of zoonotic cutaneous leishmaniasis, being virulent to mice and producing skin lesions in both mice and hamsters following intradermal inoculation. After intraperitoneal inoculation the infection spread to the genitalia, lymph nodes, viscera and skin. In contrast, mucosal leishmaniasis parasites were indistinguishable from the visceral parasites, both types failing to infect mice by intradermal or intraperitoneal inoculation and able to infect hamsters only by the intraperitoneal injection. All inoculated hamsters developed visceral disease, usually accompanied by lymph nodal and genital infection. It is concluded that L. donovani, which usually causes visceral leishmaniasis, is also the cause of mucosal leishmaniasis, while L. major is the cause of the cutaneous disease.