Background: Histoplasma capsulatum is an environmental fungus that causes opportunistic
infections in AIDS patients in endemic areas but is uncommon in Europe. It shares clinical
features with other opportunistic infections and lymphoproliferative disorders common in AIDS patients.
The World Health Organization included Histoplasma antigen tests on the Lists of Essential
In Vitro Diagnostics, however, they are not routinely available in non-endemic countries. Consequently,
mycoses can be a great challenge for clinicians in non-endemic countries.
Case Presentation: We report the case of a 42-year-old Colombian woman admitted to an Italian
university hospital with diarrhea, acute renal failure, psychomotor impairment and fever. When a
screening HIV test came back positive, she was screened for opportunistic infections with no results.
Given the severity of her clinical condition a broad spectrum antibacterial and antifungal therapy
was started in addition to HAART. A blood smear documented leucocytes inclusions, identified
as capsular structures. On suspicion of Histoplasma capsulatum the patient was started on empiric
amphotericin B. The diagnosis was confirmed by positive serology. Despite therapy, the patient
died shortly after. In the following days, the mycology laboratory managed to grow Histoplasma
capsulatum, thus confirming the diagnosis of invasive histoplasmosis in AIDS.
Conclusion: The case highlights the need for a high index of suspicion for the diagnosis of endemic
mycosis outside of endemic areas, and the necessity of expanding access to tests. Even if antigen/
antibody tests are not available, however, blood smear has worldwide feasibility and allows a