A case of brainstem encephalitis with CT scan abnormality mimicking Fisher syndrome.

A 7-year-old boy with brainstem encephalitis is described. He was drowsy in the acute phase. CSF showed pleocytosis without elevated protein. EEG showed diffuse slow wave activity during wakefulness. CT scan disclosed a low density abnormality in the basal ganglia area, which disappeared as the patient recovered. The clinical signs, CT scan abnormality and EEG findings suggest that this case is not a variant of the Guillain-Barré syndrome but is brainstem encephalitis mimicking Fisher syndrome.