Guillain-barré syndrome.

Guillain-Barré syndrome (GBS) is currently divided into the two major subtypes: acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). This review highlights relevant recent publications, particularly on the pathophysiology of AMAN. Molecular mimicry of the bacterial lipo-oligosaccharide by the human gangliosides is now considered an important cause of AMAN. Gangliosides GM1, GM1b, GD1a, and GalNAc-GD1a expressed on the motor axolemma are likely to be the epitopes for antibodies in AMAN. At the nodes or paranodes, deposition of antiganglioside antibodies initially cause reversible conduction block followed by axonal degeneration. Electrodiagnostic findings support this process. Disruption of glycolipids, which are important to maintain ion channel clustering at the nodes and paranode, may impair nerve conduction. Genetic polymorphisms of Campylobacter jejuni determine the expression of the gangliosides on the bacterial wall. In contrast, target molecules in AIDP have not yet been identified. Meta-analyses show efficacy of plasmapheresis and immunoglobulin therapy, but not corticosteroids, in hastening recovery.