Fisher Syndrome

Abstract

Fisher syndrome is a disorder characterized by acute onset of ataxia, areflexia, and ophthalmoplegia. It is regarded as a subtype of Guillain-Barré syndrome. Prior infection has previously been implicated, and a high proportion of patients prove positive for anti-GQ1b antibodies. An analysis of patients treated in our institution showed that this condition was more common in young men, and approximately 90% of all patients had a history of prior infection. Ophthalmoplegia rarely shows total extraocular muscle palsy, while abducens palsy accounts for the majority of cases. The mean time required for recovery from diplopia was approximately 70 days. GQ1b antigens are believed to be localized in large quantities around the nodes of Ranvier and Schwann cells of the extramedullary parts of the abducens, trochlear, and oculomotor nerves. Anti-GQ1b antibodies bind to these antigens, causing impaired transmission, which results in the onset of nerve paralysis. Recently, it was shown that antibodies to a ganglioside complex consisting of two different gangliosides, rather than a single ganglioside, are implicated in its onset. With an etiology based on the molecular mimicry hypothesis and the complement system has been reported, Fisher syndrome is becoming understood at the molecular genetic level.