Primary Central Nervous System Infection by Histoplasma in an Immunocompetent Adult

Central nervous system (CNS) infection by Histoplasma capsulatum is a rare disease in immunocompromised individuals in endemic areas. About one quarter of cases result from hematogenous dissemination. A 23-year-old upholsterer with chronic occipital headache had developed intracranial hypertension and dizziness, incoordination with ataxic gait, and acute confusion 5 months prior to admission. Laboratory examinations and chest roentgenogram were normal. Postcontrast T1-weighted MRI of the brain revealed a multiple ring-enhancing cerebellar, brain stem and parietal lobe lesions, and meningeal contrast enhancement. Cerebrospinal fluid culture was positive for H. capsulatum species complex, which was confirmed by phylogenetic analysis. Thirteen years after the diagnosis and treatment, there was no H. capsulatum recurrence; sequels related to complications due to the ventriculoperitoneal shunt. This case shows a primary neurological presentation of cerebral histoplasmosis, without meningitis or disseminated disease in nonimmune-compromised patient. The authors propose a categorization of the diagnosis of CNS histoplasmosis. Routine diagnostics of sibling species within the H. capsulatum complex proved to be difficult.