Chronic central nervous system histoplasmosis in an immunocompetent patient

Background: Histoplasma capsulatum is an endemic fungus in America that may present as a lung self-limiting infection or be asymptomatic. Disseminated histoplasmosis can occur in cell-mediated immunity disorders and acquired immunodeficiency syndrome. Isolated central nervous system (CNS) histoplasmosis is uncommon, furthermore in immunocompetent patients.

Methods: A 34 year old inmunocompetent male is reported. He presented with several pathogenic forms of neurohistoplasmosis: chronic meningitis, meningovascular histoplasmosis with stroke, acute myelopathy and chronic recurrent hydrocephalus. Other causes of chronic infectious meningitis were ruled out. Cerebrospinal flow (CSF) analysis showed an increased white cell count, hyperproteinorraquia and decrease of glucose levels. Brain magnetic resonance imaging (MRI) showed hydrocephalus and gadolinium enhancement of the meninges; a spinal cord MRI detected a cervical and thoracic myelopathy. A chronic unspecific inflammatory process and absence of granulomata were observed in a meninge biopsy. Electronic microscopy showed the presence of yeasts in the CSF. Histoplasma capsulatum was isolated in a specific culture from two consecutive CSF samples. The patient was treated with ev amphotericin B and fluconazol, plus 6 months of oral itraconazole.

Conclusions: Isolated chronic CNS histoplasmosis may present as recurrent episodes of stroke, meningitis, myelopathy and hydrocephalus. CSF specific culture can help in the diagnosis.