AIDS-related Histoplasma capsulatum var. capsulatum infection: 25 years experience of French Guiana.

Objective: Histoplasma capsulatum var. capsulatum infection is a major AIDS-defining illness in French Guiana. Although it affects South and Central American countries, the number of published cases is low. We present the largest series of AIDS-related histoplasmosis. The aim of this work is to describe clinical features and to help optimize investigations in settings where antigen detection methods are not available.
Design: Two hundred cases of AIDS-related histoplasmosis, diagnosed in the hospitals of French Guiana, were included retrospectively between 1982 and 2007.
Results: At the time of diagnosis, 92% of patients did not receive highly active antiretroviral therapy. CD4 cell count was less than 100 cells/microl for 80% of them. Most patients had fever, lymphadenopathies, and pulmonary and digestive symptoms. Neurological signs and skin/mucosal locations were less common. Other opportunistic infections were associated in 36.6% of cases (mostly tuberculosis). In most of the patients, lactic dehydrogenase was at least four times the normal value, and there was a moderate increase of aspartate aminotransaminase but not alanine aminotransaminase levels. Bone marrow aspirations were useful, but cultures of liver and lymphadenopathy specimens were the most contributive. Following treatment initiation, 17.5% died within a month. Presumptive treatment was started before diagnostic confirmation in 14.3% of the cases.
Conclusion: In high prevalence settings, histoplasmosis often revealed AIDS in severely immunodeficient and poorly followed patients. In the absence of a quick sensitive technique, skin smear and fungal tissue cultures are contributive. Nevertheless, given the diagnostic delays and the poor prognosis, presumptive treatment with amphotericin B-containing regimens should be recommended when clinical and epidemiological contexts are evocative.