Two patients admitted to the hospital because of severe bacterial infection were diagnosed as having visceral leishmaniasis. The types of bacterial infection were perianal abscess and pneumonia; Escherichia coli and Streptococcus pneumoniae were isolated from exudates and blood cultures, respectively. A third patient admitted because of acute necrotizing infection of the pharynx and visceral leishmaniasis is also discussed. Cultures from this patient failed to yield pathogens. Anemia, leukopenia, or thrombocytopenia was present in all patients, and bone marrow aspirate revealed the presence of Leishmania in macrophages. We conclude that in areas where leishmaniasis is endemic, early bone marrow aspirate should, in most instances, be performed in patients with bacterial infection associated with anemia, leukopenia, or thrombocytopenia if hepatomegaly and/or splenomegaly is present. © 1990 by The University of Chicago.