Serum antibody against a peripheral nerve myelin ganglioside, LM1, in Guillain-Barre syndrome

Serum IgG antibody against LM1, the predominant ganglioside in the human pe ripheral nerve myelin, was found in 7 out of 140 patients with Guillain-Bar re syndrome (GBS) in the acute phase, 1 out of 33 patients with chronic inf lammatory demyelinating polyneuropathy (CIDP), and 2 out of 47 patients wit h Miller Fisher syndrome (MFS). Anti-LM1 IgM antibody was detected only in 2 patients, each with GBS and MFS. The clinical and electrophysiological fe atures of the seven GBS patients with anti-LM1 IgG antibody in the serum we re investigated. Six patients recovered to grade 1 within one month of the onset of neuropathy. Electrophysiological studies revealed demyelination in five patients, of which one had axonal damage in addition, whereas suffici ent evidence of demyelination or axonal degeneration was not observed in th e remaining two. Five had a respiratory tract infection before the onset of neuropathy, and also had serum anti-GQ1b IgG antibody. IgG antibody agains t LM1 might he involved in the pathogenetic mechanisms of GBS, as a possibl e demyelinating factor. Presence of both anti-GQ1b and anti-LM1 antibodies may be associated with some infectious agent(s) affecting the respiratory t ract. (C) 1999 Elsevier Science B.V. All rights reserved.