title: [Steroid responsive chronic brainstem encephalitis featuring mental symptoms, abnormal eye movement and cerebellar ataxia].
abstract: A 53-year-old man presented with progressive ataxia two and a half years prior to admission. Initially he was treated in a local hospital for 4 months with a diagnosis of spinocerebellar degeneration. Subsequently he developed psychomotor excitement with hallucination and was admitted to a mental hospital for 7 months with a diagnosis of Wernicke's encephalopathy. After a year of partial remission, he presented with increasing difficulty in thinking and walking. On admission he developed mental agitation and excitement, ocular flutter and opsoclonus, and prominent cerebellar ataxia. A lymphocytic pleocytosis in the CSF and a high-intensity lesion in the superior cerebellar peduncle of the upper brainstem revealed on a T2-weighted MRI led to a diagnosis of brainstem encephalitis. Treatment with steroid (two series of 3 days of 1,000mg methylprednisolone DIV, followed by 60mg oral prednisolone) brought about a dramatic improvement in mental and ocular symptoms corresponding with the CSF findings. He was left with mild cerebellar ataxia and returned to work on a small dose of steroids. Differential diagnoses including Bickerstaff's encephalitis and pathomechanism were discussed.
authors.affiliation: Department of Neurology, Yokohama City Hospital, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Watanabe
authors.forename: H
authors.initials: H
authors.lastname: Tachikawa
authors.forename: R
authors.initials: R
authors.lastname: Hayashi
authors.forename: M
authors.initials: M
authors.lastname: Honda
mesh_terms: D001933:Brain Stem / Q000473:pathology*; D002524:Cerebellar Ataxia / Q000209:etiology*; D002908:Chronic Disease; D004660:Encephalitis / Q000150:complications* / Q000175:diagnosis / Q000188:drug therapy* / Q000473:pathology; D006212:Hallucinations / Q000209:etiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008775:Methylprednisolone / Q000008:administration & dosage*; D008875:Middle Aged; D015835:Ocular Motility Disorders / Q000209:etiology*; D011239:Prednisolone / Q000008:administration & dosage*; D011595:Psychomotor Agitation / Q000209:etiology*
chemical_list: D011239:Prednisolone; D008775:Methylprednisolone