[Acute disseminated encephalomyelitis (ADEM)-like exacerbation in the patients with cryptococcus meningitis treated successfully by steroid pulse therapy].

A 58-year-old man was admitted to our hospital with suspicion of aseptic meningitis. He had been well until the day before admission, when he became suffering from headache and nausea. Cerebral spinal fluid (CSF) analysis on admission revealed Cryptococcus neoformans. Neurological examination and brain CT scan showed no abnormality. On the 5th hospital day, he noticed ataxia and weakness in his right extremities and soon fell into drowsy to comatose state. CSF study revealed marked elevation of pleocytosis and oligoclonal IgG bands. The T2 weighted image of brain MRI showed multiple high intensity areas, mainly in the white matter, in cerebellar hemisphere, vermis, left medulla oblongata, left occipital lobe and parieto-occipital lobe. Steroid pulse therapy remarkably improved neurological deficit as well as MRI abnormalities. He became alert at the next day. Ataxia and motor weakness disappeared in a week. Laboratory examination before the pulse therapy revealed impairment of T cell response to mitogens and reduced number of CD8-positive cells. These abnormalities in the cell-mediated immunity were completely corrected by the steroid pulse therapy. It was hypothesized that cryptococcus infection induced the autoimmune mechanism which resulted in the ADEM-like exacerbation.