A-waves in Guillain-Barré syndrome: Correlation with electrophysiological subtypes and antiganglioside antibodies

摘要

Objective: To investigate the relationship of A-waves with conventional electrophysiological subtypes of Guillain-Barré syndrome (GBS), as well as with anti-ganglioside antibodies. Methods: The subjects consisted of 30. GBS patients who were classified into acute inflammatory demyelinating polyradiculoneuropathy (AIDP), acute motor axonal neuropathy, and unclassified based on the results of nerve conduction studies. " Abundant A-waves" were defined for the upper-limb nerves (median and ulnar nerves) using receiver-operator characteristic curves. The presence or absence of IgG anti-ganglioside antibodies was also noted. Results: Abundant A-waves at weeks 3-6 from onset were observed in 64% of the 14 AIDP patients and 0% of 16 non-AIDP patients, and in 60% of 15 antibody-negative patients and 0% of 15 antibody-positive patients. In the earlier period, this relationship was less clear. The correlation between the conventional electrophysiological subtypes and antibodies was present, but was much weaker. Conclusions: Abundant A-waves in GBS after the acute phase were strongly associated with demyelination that was not mediated by antiganglioside antibodies, possibly through the mechanism of proximal re-excitation induced by electrical inhomogeneities due to segmental demyelination. Significance: Abundant A-waves are promising as a novel reliable marker of demyelination.