Background Whether or not antiganglioside antibodies are related to axonal or demyelinating Guillain–Barré syndrome (GBS) is still a matter of controversy, as detailed in previous studies conducted in Western and Asian countries.

Objective To clarify whether antiganglioside antibodies are associated with axonal dysfunction in Japanese and Italian GBS patient cohorts.

Methods Clinical and electrophysiological profiles were reviewed for 156 GBS patients collected from Japan (n=103) and Italy (n=53). Serum IgG antibodies against GM1, GM1b, GD1a and GalNAc-GD1a were measured by ELISA in the same laboratory. Electrodiagnostic criteria and results of serial electrophysiological studies were used for classification of GBS subtypes: acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN).

Results In both Japanese and Italian cohorts, any of the antibodies were positive in 36% of the patients, and antibody positivity had a significant association with the AMAN electrodiagnosis. Approximately 30% of Japanese and Italian antiganglioside positive patients showed the AIDP pattern at the first examination whereas sequential studies showed that most finally showed the AMAN pattern. Clinically, seropositive patients more frequently had preceding diarrhoea and pure motor neuropathy in both Japanese and Italian cohorts; vibratory sensation was normal in 97% of Japanese and in 94% of Italian seropositive patients.

Conclusions In GBS, clinical and electrophysiological features appear to be determined by antiganglioside antibodies, and the antibodies are associated with motor axonal GBS in both Japan and Italy. Classification of the GBS subtypes as a disease entity should be made, combining the results of antiganglioside assays and serial electrodiagnostic studies.