PIP: 50 children under the age of 15 years were studied who had been hospitalized in two hospitals in the Dominican Republic with HIV diagnosed by the presence of biphasic hyperbilirubinemia and elevation of glutamic-pyruvic and glutamic-oxalacetic transaminases. The sera of the patients were examined for the presence of leptospirotic immunoglobulin M (IgM) antibodies by means of the enzymatic immunoassay method (UREASA-ELISA). The Leptospira-positive sera were also investigated for the presence of hepatitis B surface antigen (HBsAg) and for the IgM antibody (ab) of the hepatitis A virus (ab-HAV) by ELISA. 5 cases were positive for IgM Leptospira antibodies (10%), not finding in this percentage the presence of HBsAg; 3 of the 5 Leptospira-positive samples demonstrated the presence of ab-HVA-IgM. Only 2 cases (4%) presented IgM Leptospira antibodies. Out of the 5 cases with IgM antibodies, males predominated (3/5). When compared to negative cases, however, there were more rural elements among them than in negative cases: regarding origins (10% vs. 16%), agricultural workers (40% vs. 20%), contact with cattle and fresh water (80% vs. 40%), and daily contact with humid soil in living quarters (60% vs. 48%). The clinical picture of the 5 positive cases featured myalgia (p = 0.05) and abdominal pain (p = 0.05). The stiffness of neck was relatively more frequent in positive cases (20%) than in negative cases (7%); also, fever (100% vs. 80%), vomiting (60% vs. 22%), headache (80% vs. 56%), constipation (20% vs. 9%), and hepatomegaly (100% vs. 71%). There was clear evidence that leptospirotic infection must be watched and also its association with acute infectious hepatitis.