Cryptococcal meningitis misdiagnosed as Alzheimer's disease: complete neurological and cognitive recovery with treatment.

A sixty-two year old man, with a background of Alzheimer's disease for the past three years, acutely presented with imbalance, headaches, and dizziness. Examination revealed a profound frontal disinhibited and dysexecutive syndrome and brain imaging notable for leptomeningeal enhancement; laboratory data confirmed cryptococcal meningitis. Four months after treatment, the patient was normal neurologically, cognitively and neuroradiologically. The specific cognitive impairment and neuroradiological findings may be clues to differing dementia etiologies.