Concurrent human infection with Leishmania donovani and Leishmania braziliensis braziliensis.

In the suburban district of Campo Grande, Municipality of Rio de Janeiro (Brazil) cases of both Leishmania domovani and L. b. braziliensis infections occur. In March 1982 we examined a white male child, five years old, with fever, weight loss and distended abdomen, symptoms said to have started three months before. After the first month a papular lesion appeared on his forehead, rapidly increasing in size and becoming ulcerated: Parasites were isolated from both the ulcer and the bone marrow by culturing in BHI-agar with rabbit blood and a liquid overlay of modified LIT medium. Using the techniques of zymodeme analysis, schizodeme analysis and serodeme analysis using monoclonal antibodies, the parasite from the ulcer was identified as L. b. braziliensis and that from the bone marrow as L. donovani. This seems to be the first described case of concurrent infection of man with a visceral and cutaneous Leishmania. It indicates that, at least in humans, a previous infection with L. donovani does not protect against L. b. braziliensis. This result has important implications for the development of vaccines against leishmaniases.