Guillain-Barre syndrome is divided into two subtypes: acute inflammatory demyelinating polyneuropathy, and acute motor axonal neuropathy. Autoantibodies to gangliosides GM1, GM1b, GD1a, or GalNAc-GDla were proposed as serologic markers of acute motor axonal neuropathy in adults. In a previous study of Japanese children with Guillain-Barre syndrome, acute motor axonal neuropathy was associated with anti-GM1 immunoglobulin G antibodies. Larger, comprehensive studies are required to confirm this finding. The present study revealed that immunoglobulin G antibodies were against GM1 (34%), GM1b (22%), GD1a (25%), GalNAC-GD1a (13%), and any of these (44%) in 32 Japanese children with Guillain-Bane syndrome. Patients who had the autoantibodies more often manifested previous diarrhea (71% vs 11%, P = 0.001), acute motor axonal neuropathy (64 % vs 11 %, P = 0.003), and slower recovery (healthy at final follow-up: 29% vs 78%, P = 0.011; able to run with minor signs, 64 % vs 11 %, P = 0.003) than patients who did not. The clinical features were consistent with those in adults carrying anti-ganglioside antibodies. Anti-ganglioside antibody testing may help predict outcomes in pediatric patients with Guillain-Barre syndrome who prefer not to undergo repeated nerve-conduction studies. (C) 2008 by Elsevier Inc. All rights reserved.