Nationwide survey of patients in Japan with Bickerstaff brainstem encephalitis: epidemiological and clinical characteristics

摘要: Backgroud Information regarding the epidemiological background of Bickerstaff brainstem encephalitis (BBE) is limited. Methods We conducted a nationwide survey BBE in Japanese population two steps: first aimed to identify patients with for specified 3 year period and second evaluate whether clinical picture met our diagnostic criteria BBE. Results The number was estimated as 704 (95% CI 478 930) over 3 years. annual onset roughly 100 cases, which accounted 43% encephalitis. slightly male predominant often young onset. Among patients, characterised by antecedent infectious symptoms, oropharyngeal palsy sensory disturbance at distal extremities absent or decreased tendon reflexes, addition triad symptoms (external ophthalmoplegia, ataxia impaired level consciousness) shorter duration peak, good outcome. Anti-GQ1b antibodies were present 75% cases. Several atypical features without anti-GQ1b also identified. These cases had marked CSF pleocytosis, abnormal brain MRI findings longer peak sometimes considerable residual deficits. Conclusions rare disorder but accounts major proportion consists typical Typical has similar neurological serological Fisher syndrome shows recovery whereas delayed recovery, negative antibodies, other possible pathogeneses.