Usefulness of anti-GQ1b IgG antibody testing in Fisher syndrome compared with cerebrospinal fluid examination.

Fisher syndrome (FS), a variant of Guillain-Barré syndrome (GBS), is a rare disorder, and there are few reported studies of a large number of patients with FS. Cerebrospinal fluid (CSF) albuminocytological dissociation was found in 59% of 123 FS patients during the first 3 weeks of illness, while serum anti-GQ1b IgG antibody was positive in 85%. Whereas the incidence of CSF albuminocytological dissociation increased from the first to second weeks in FS, anti-GQ1b IgG antibody peaked in the first week, but there was no CSF albuminocytological dissociation. Statistically, anti-GQ1b antibody testing was superior to a CSF examination in supporting a diagnosis of FS during the first 3 weeks of illness, especially in the first week.