Search

Monospecific IgG antibodies to GD1b ganglioside (GD1b-specific antibodies) have been found in patients with acute ataxic neuropathy and Guillain-Barré syndrome, but the association of the GD1b-specific antibodies with specific neurological conditions has yet to be established. We tested sera from more than 10,000 patients with various neurological disorders, and found six sera, which contained IgG antibodies to GD1b, but not to LM1, GM1, GM1b, GD1a, GalNAc-GD1a, GT1a, GT1b and GQ1b. All six patients who carried GD1b-specific antibodies presented with acute onset of ataxia and monophasic course of the illness, of whom five demonstrated cerebellar-like ataxia. Four patients had antecedent symptoms of upper respiratory tract infection. The six patients demonstrated areflexia, and four complained of distal numbness. All the six patients who had the GD1b-specific antibodies carried IgG antibodies to complex of GQ1b/GM1 and GT1a/GM1. GD1b-specific antibodies were significantly absorbed by GQ1b/GM1 and GT1a/GM1 and anti-GQ1b/GM1 and -GT1a/GM1 antibodies were absorbed by GD1b. In conclusion, the GD1b-specific antibodies, which recognizes GQ1b/GM1 or GT1a/GM1 complex, are associated with acute ataxia. [ABSTRACT FROM AUTHOR]

Whether Bickerstaff's brainstem encephalitis (BBE) is a distinct disease or a subtype of Fisher syndrome (FS) is unclear as there have been no clinical studies with sufficiently large numbers of patients with FS or BBE. Our aim was to clarify the nosological relationship. Medical records of patients suffering acute ophthalmoplegia and ataxia within four weeks of onset were reviewed. BBE was the diagnosis for patients with impaired consciousness, FS for those with clear consciousness and areflexia. Clinical features, neuroimages, and laboratory findings were analyzed. Patients were grouped as having BBE (n = 53), FS (n = 466), or as unclassified (n = 62). The BBE and FS groups had similar features; positive serum anti-GQ1b IgG antibody (68 % versus 83 %), antecedent Campylobacter jejuni infection (23 % versus 21 %), CSF albuminocytological dissociation (46 % versus 76 %), brain MRI abnormality (11 % versus 2 %), and abnormal EEG findings (57 % versus 25 %). BBE (n = 4) and FS (n = 28) subgroups underwent detailed electrophysiological testing. Both groups frequently showed absent soleus H-reflexes, but normal sensory nerve conduction (75 % versus 74 %) and a 1-Hz power spectrum peak on postural body sway analysis (67 % versus 72 %). Common autoantibodies, antecedent infections, and MRI and neurophysiological results found in this large study offer conclusive evidence that Bickerstaff's brainstem encephalitis and Fisher syndrome form a continuous spectrum with variable CNS and PNS involvement. [ABSTRACT FROM AUTHOR]