Very commonly encountered in the United States, histoplasmosis is rare in Europe, where only 27 patients have so far been infected by this mycosis. In Africa, two varieties of histoplasmosis have been observed: those due to H. capsulatum and H. duboisii. Histoplasmosis due to H. capsulatum is one of the twelve secondary infectious diseases listed in the surveillance definitions of AIDS. This complication has been described only in approximately 20 patients with AIDS; all patients had stayed on the American Continents. We report the case of a 30-year-old African male who lived in Switzerland and in Zaire. With AIDS and multiple Kaposi's sarcoma, the patient died from disseminated histoplasmosis due to H. capsulatum; a peripheral blood smear obtained a few hours before death revealed numerous typical yeast forms of H. capsulatum inside polymorphonuclear leukocytes. Post-mortem examination and cultures confirmed the diagnosis of disseminated histoplasmosis. Histoplasmosis should be suspected in AIDS patients even in Europe, especially where they have stayed in endemic areas. Examination of blood smears and bonemarrow aspirate may allow early recognition of the disease and permit appropriate treatment with amphotericin B and ketoconazole.