Purpose: Histoplasmosis due to Histoplasma capsulatum is a granulomatous fungic infection which appears opportunistic and disseminated in immunocompromised patients, especially among HIV patients in whom it can lead to death. Histoplasmosis is endemic in numerous areas worldwide, but in Europe most of the cases reported are imported. We describe the clinical features and the available diagnosis methods issued from our experience in French Guyana.
Methods: Contamination occurs by inhalation of spores contained in dust. Most endemic areas are located on the American continent, including the French West Indies, where the incidence of histoplasmosis among HIV patients in French Guyana varies from 1.2 to 2.2% per year. In non-immunocompromised patients, histoplasmosis is asymptomatic most of the time. In HIV patients, the disseminated form is common and may occur many years after exposure to the fungus.
Results: Non-specific symptoms, similar to those of either tuberculosis or other opportunistic infections, may reveal disseminated histoplasmosis in patients with AIDS. Early treatment (amphotericin B or itraconazole) is effective; however, it should be followed by a lifelong antifungic treatment (itraconazole) to prevent relapse.
Conclusion: The infection should be suspected in any febrile HIV-infected patient with CD4 blood cell count < 200/mm3, if he/she ever travelled in an endemic zone. Direct examination of smear relating to clinical symptoms help guide diagnosis, while culture will confirm it after at least 4 weeks. Efficient serologic techniques for HIV-infected patients are not available in Europe.