S. Kuwabara et al., IGG ANTI-GM1 ANTIBODY IS ASSOCIATED WITH REVERSIBLE CONDUCTION FAILURE AND AXONAL DEGENERATION IN GUILLAIN-BARRE-SYNDROME, Annals of neurology, 44(2), 1998, pp. 202-208
To investigate the pathophysiological role of anti-GM1 antibody in Gui
llain-Barre syndrome (GBS), we reviewed sequential nerve conduction st
udies of 345 nerves in 34 GBS patients. Statistically significant corr
elation between IgG anti-GM1 antibodies and electrodiagnoses was found
. Sixteen IgG anti-GM1-positive patients were classified as having acu
te motor or acute motor sensory axonal neuropathy (AMAN or AMSAN) (12
patients), as having acute inflammatory demyelinating polyneuropathy (
AIDP) (3 patients), or as undetermined (1 patient) by electrodiagnosti
c criteria Besides axonal features, there was rapid resolution of cond
uction slowing and block. In 3 patients initially diagnosed as having
AIDP, conduction slowing was resolved within days, and 1 of them and 3
AMAN patients showed markedly rapid increases in amplitudes of distal
compound muscle action potentials that were not accompanied by prolon
ged duration and polyphasia The time courses of conduction abnormaliti
es were distinct from those in IgG anti-GM1-negative AIDP patients. Ra
pid resolution of conduction slowing and block, and the absence of rem
yelinating slow components, suggest that conduction failure may be cau
sed by impaired physiological conduction at the nodes of Ranvier. Reve
rsible conduction failure as well as axonal degeneration constitutes t
he pathophysiological mechanisms in IgG anti-GM1-positive GBS. In both
cases, immune-mediated attack probably occurs on the axolemma of moto
r fibers.