Clinical features and response to treatment in Guillain-Barré syndrome associated with antibodies to GM1b ganglioside.

GM1b is a minor ganglioside in human peripheral nerves. Serum anti-GM1b antibodies frequently are present in patients with Guillain-Barré syndrome (GBS). In this collaborative study, we investigated the antecedent infections, clinical features, and response to treatment of GBS patients with anti-GM1b antibodies. Of 132 GBS patients who participated in the Dutch GBS trial that compared the effect of intravenous immunoglobulins and plasma exchange, 25 (19%) patients had anti-GM1b antibodies. IgM antibodies were present in 14, IgG antibodies in 15, and both isotypes in 4 patients. The 25 patients with anti-GM1b antibodies had a clinical pattern distinct from that of the other 107 GBS patients. They more often had an episode of gastrointestinal illness and frequently showed serological evidence of recent infection by Campylobacter jejuni. The anti-GM1b-positive subgroup was marked by more rapidly progressive, more severe, and predominantly distal weakness. Cranial nerve involvement and sensory deficits were less common in the patients with anti-GM1b antibodies. The presence of anti-GM1b antibodies was associated with slower recovery. The clinical manifestations predominantly were associated with anti-GM1b antibodies of the IgG isotype. Fourteen (56%) of the 25 patients with anti-GM1b antibodies also had anti-GM1 antibodies. The group of patients with both antibodies was clinically more homogeneous and had a more rapidly progressive, pure motor neuropathy. The subgroup of anti-GM1b-positive GBS patients responded well to treatment with immunoglobulins but not to plasmapheresis. The distinctive clinical features of the patients with anti-GM1b antibodies show that acute motor neuropathy represents a specific subgroup within GBS and that recognizing these patients may have consequences as to the choice of therapy.