Atypical Bickerstaff brainstem encephalitis: ataxic hypersomnolence without ophthalmoplegia

Abstract

Ophthalmoplegia can be absent or incomplete in BBE, and the absence of this clinical feature should not exclude BBE from the clinicians' differential. Such cases of incomplete BBE could be defined as 'ataxic hypersomnolence without ophthalmoplegia'.

Another CNS phenotype of anti-GQ1b antibody syndrome

“…Another explanation is the diverse fine specificities of anti-GQ1b antibodies, which have already been investigated within PNS phenotypes of anti-GQ1b antibody syndrome: anti-GQ1b antibodies from MFS patients rarely cross-react with GD1b ganglioside, whereas those from patients with acute sensory ataxic neuropathy without ophthalmoplegia frequently do 5. Disappointingly, data regarding the cross-reactivity of anti-GQ1b antibodies are not available in the current description3 and it is impossible to evaluate this hypothesis in the CNS phenotypes of anti-GQ1b antibody syndrome. If this is true also in the CNS phenotypes, we should open the door for further assessment of anti-ganglioside antibodies in the CNS disorders.…”

“…Wakerley et al 3 describe two cases of atypical CNS phenotype of anti-GQ1b antibody syndrome, in which the neurological picture and clinical course resemble that of BBE, except for absent or incomplete ophthalmoplegia. Ophthalmoplegia is often the predominant feature in BBE and, conversely, lack of ophthalmoplegia in cases of brainstem encephalitis has been recognised as the important cue for unlikeliness of anti-GQ1b antibody syndrome.…”

“…Ophthalmoplegia is often the predominant feature in BBE and, conversely, lack of ophthalmoplegia in cases of brainstem encephalitis has been recognised as the important cue for unlikeliness of anti-GQ1b antibody syndrome. The observation by Wakerley et al 3 indicates that this is not always true, and that anti-GQ1b antibody testing should be considered in the case of acutely progressive impaired consciousness with ataxia regardless of whether ophthalmoplegia is apparent. This is especially important in the case of (brainstem) encephalitis/encephalopathy without abnormalities in cerebrospinal fluid analysis and brain imaging (CT/MRI) like typical BBE.…”

Bickerstaff brainstem encephalitis: more common than we think?

“…The report by Wakerley et al 4 describes two patients presenting acute ataxia and hypersomnolence without ophthalmoplegia, and anti-ganglioside assay showed high titer of serum IgG anti-GQ1b antibodies. One patient received immunoglobulin therapy and had returned to normal 4 weeks later, whereas the other had spontaneous recovery within 4 weeks.…”

“…In both ‘incomplete’ FS and BBE, the positivity of anti-GQ1b antibodies strongly supports the diagnosis, and the antibody should be measured in these regional variants. Wakerley et al 4 proposed the term, ‘ataxic hypersomnolence without ophthalmoplegia’, and it is possible that there is another reverse variant of ‘ophthalmoplegic hypersomnolence without ataxia’. BBE may be more common than we think.…”