Anti-GQ1b ganglioside antibody and ophthalmoplegia of undetermined cause.

BACKGROUND/AIM Serum antibody against ganglioside GQ1b is reported to be closely associated with immune mediated ophthalmoplegia in the Fisher and Guillain-Barré syndromes. Its presence against glycolipids, in particular ganglioside GQ1b, was investigated in patients with ophthalmoplegia of unknown origin. METHODS 16 patients with ophthalmoplegia, the cause of which could not be confirmed from clinical findings or diagnostic testing, were tested. 34 patients who had ophthalmoplegia of definite cause, 16 healthy people, and 23 patients with typical Fisher syndrome served as the controls. The ELISA was used to check for serum antibodies against glycolipids in all study participants. RESULTS Two of the 16 patients with ophthalmoplegia of unknown cause had serum IgG antibody against GQ1b but not against other glycolipids, and 22 of the 23 patients with typical Fisher syndrome had this antibody. No anti-GQ1b antibodies were found in the patients with ophthalmoplegia of definite cause or in the normal controls. CONCLUSION A common underlying cause appears to bring about the pathogenesis of palsy in Fisher syndrome and in the ophthalmoplegia with positive anti-GQ1b IgG antibody, called atypical Fisher syndrome. This antibody may prove a useful clinical marker for differentiating Fisher syndrome, typical and atypical, in patients with ophthalmoplegia.