Cognitive impairment and memory loss associated with Histoplasmosis: A case study

Histoplasmosis is a rare disease caused by inhalation of the fungus Histoplasma capsulatum. It can spread via cerebral circulation to the central nervous system as a manifestation of a disseminated infection; particularly in patients with immune suppression, which can result in isolated ring-enhancing lesions and inflammation in the brain. Of the reported disseminated histoplasmosis cases (approximately 1 in 2000 per year), only 5-20% have evidence of central nervous system involvement. This paper reviews a single case study of a 57-year-old female diagnosed with disseminated CNS histoplasmosis. Patients complaints included reduced short-term memory, word-finding problems, and difficulty organizing, making decisions, getting lost while driving, recalling names, retaining information while reading, and slowed processing speed. There was also a history of mild depression and anxiety. Direct testing revealed deficits in multiple cognitive domains including complex attention, processing speed, semantic fluency, visual scanning, motor speed, set-shifting, naming, nonverbal memory, and verbal memory. Neuropsychological deficits suggest cortical and subcortical brain dysfunction, including anterior, temporal, and mesialoral regions. This case illustrates the need for neuropsychologists to understand histoplasmosis, the related pathophysiology, and the neuropsychological impact; particularly with the potential for delayed progression.