title: Bulbar involvement in patients with antiganglioside antibodies against NeuNAc(alpha2-3)Gal.
abstract: BACKGROUND
  Reactivity against terminal NeuNAc(alpha2-3)Gal, common to several gangliosides such as GD1a, GT1b and GM3, has rarely been reported. The authors recently described a patient with a clinical picture of acute relapsing sensory ataxic neuropathy and bulbar involvement in whom they demonstrated concomitant reactivity against NeuNAc(alpha2-3)Gal and disialosyl epitopes. The authors suggested a correlation between NeuNAc(alpha2-3)Gal reactivity and bulbar involvement.
  
  
  OBJECTIVE
  To determine the frequency of reactivity against terminal NeuNAc(alpha2-3)Gal in acute and chronic immune-mediated disorders, and its possible correlation with bulbar involvement.
  
  
  METHODS
  The authors retrospectively reviewed reactivity in the serum of more than 3000 consecutive patients with acute and chronic disorders in which antiganglioside antibodies were studied. The authors selected those patients who were simultaneously positive, by ELISA or thin-layer chromatography, for IgG or IgM antibodies anti-GM3, GD1a and GT1b, and reviewed their clinical features.
  
  
  RESULTS
  Reactivity against NeuNAc(alpha2-3)Gal, shared by GM3, GD1a and GT1b gangliosides, was detected in 10 patients: isolated in one patient, and concomitant with reactivity against other gangliosides in the remaining patients. Reactivity against NeuNAc(alpha2-3)Gal was frequently associated (8/10) with symptoms suggestive of bulbar involvement, such as dysphagia, dysarthria or dysphonia. Severe respiratory failure requiring mechanical ventilation was observed in four patients.
  
  
  CONCLUSIONS
  Reactivity against the NeuNAc(alpha2-3)Gal epitope is rare and is generally found in association with reactivity against the disialosyl epitope. It can be detected in patients with acute or chronic disorders and could be a serological marker of clinical bulbar involvement and, to a lesser extent, associated with the development of severe respiratory failure.
authors.affiliation: Department of Neurology, Neuromuscular Diseases Unit, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain. rrojas@santpau.cat
authors.forename: Ricard
authors.initials: R
authors.lastname: Rojas-Garcia
authors.forename: Eduard
authors.initials: E
authors.lastname: Gallardo
authors.forename: Noemi
authors.initials: N
authors.lastname: De Luna
authors.forename: Candido
authors.initials: C
authors.lastname: Juarez
authors.forename: Eugenia
authors.initials: E
authors.lastname: Martinez-Hernandez
authors.forename: Alejandra
authors.initials: A
authors.lastname: Carvajal
authors.forename: Carlos
authors.initials: C
authors.lastname: Casasnovas
authors.forename: Eva
authors.initials: E
authors.lastname: Fages
authors.forename: Pablo
authors.initials: P
authors.lastname: Davila-González
authors.forename: Isabel
authors.initials: I
authors.lastname: Illa
mesh_terms: D000918:Antibody Specificity; D010244:Bulbar Palsy, Progressive / Q000276:immunology* / Q000503:physiopathology*; D005260:Female; D005679:G(M3) Ganglioside / Q000276:immunology*; D005732:Gangliosides / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D007075:Immunoglobulin M / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D005679:G(M3) Ganglioside; D005732:Gangliosides; D007074:Immunoglobulin G; D007075:Immunoglobulin M; C021298:ganglioside, GD1a