Diagnosis, pathogenesis and treatment of Miller Fisher syndrome and related disorders: clinical significance of antiGQ1b IgG antibody.

Miller Fisher syndrome is a variant of Guillain-Barré syndrome, characterized by ophthalmoplegia, ataxia and areflexia. The antiGQ1b immunoglobulin G antibody is a specific marker of Miller Fisher syndrome and related disorders, such as Guillain-Barré syndrome with ophthalmoplegia, atypical Miller Fisher syndrome characterized by acute ophthalmoplegia or acute ataxia and Bickerstaff's brainstem encephalitis. The antiGQ1b immunoglobulin G antibody may play some important roles in the pathogenesis of Miller Fisher syndrome and related disorders. Possible mechanisms are discussed. Molecular mimicry between an infectious agent of the antecedent infection and the ganglioside may be a mechanism of the antibody production. Plasmapheresis or intravenous immunoglobulin therapy may be warranted for Miller Fisher syndrome and Bickerstaff's brainstem encephalitis, as well as Guillain-Barré syndrome with ophthalmoplegia.