Abstract
Histoplasma capsulatum is one of the most common fungal respiratory infections in the world. CNS histoplasmosis is rare and difficult to diagnose because it is often overlooked or mistaken for other pathologies due to its non-specific symptoms. Failure to quickly diagnose CNS histoplasmosis leads to a poor prognosis. A 32-year-old homosexual Hispanic male with advanced AIDS presented with an altered mental status and reported confusion for the past three months. He had a GSC scale of 12, repetitive non-fluent speech, and a disconjugate gaze with a right gaze preference. Lung-CT findings indicated a pulmonary histoplasmosis infection. An MRI of the brain revealed a ring-enhancing lesion in the left caudate nucleus. A CT guided left retroperitoneal node biopsy was performed and indicated a benign inflammatory process with organisms compatible with fungal yeast. Treatment with amphotericin B followed by itraconazole was initiated in spite of negative CSF cultures and proved effective in mitigating associated CNS lesions and resolving neurologic deficits. The patient was discharged three weeks later in stable condition. Six weeks later, his left basal ganglia mass decreased from 30 x 36.9mm to 28.3 x 23.3mm. Early recognition of symptoms and proper steps are key in improving outcomes of CNS histoplasmosis. Aggressive medical management is possible in treatment of intracranial deep mass lesions, and disseminated histoplasmosis with CNS involvement can be appropriately diagnosed and treated, despite negative CSF and serology studies.