title: Miller Fisher syndrome: axonal, demyelinating or both?
abstract: Controversy exists concerning whether Miller Fisher syndrome (MFS) is the result of a predominantly axonal or demyelinating polyneuropathy and whether the Guillain-Barré syndrome variant of acute ataxia and areflexia without ophthalmoplegia, ataxic Guillain-Barré syndrome (atxGBS), has a distinct pathophysiology. We explored these issues by reviewing the electrophysiologic features of 6 patients with MFS and 2 patients with atxGBS. EMG laboratory records were reviewed and electrophysiologic findings were categorized as axonal or demyelinating neuropathy using previously defined criteria. Of the 6 patients with MFS, 5 had electrophysiologic evidence suggestive of an axonal, predominantly sensory polyneuropathy; only 1 patient met criteria for demyelinating polyneuropathy. Both patients with atxGBS had demyelinating sensorimotor polyneuropathy. Electrophysiologic abnormalities in MFS typically suggest a predominantly axonal, sensory polyneuropathy, though demyelinating forms occur and may be under-diagnosed using current criteria. AtxGBS, in our experience, is a predominantly demyelinating polyneuropathy.
authors.affiliation: Department of Neurology, Beth Israel Medical Center, New York, New York, USA. SScelsa@BethIsraelNY.Org
authors.forename: S N
authors.initials: SN
authors.lastname: Scelsa
authors.forename: S
authors.initials: S
authors.lastname: Herskovitz
mesh_terms: D000328:Adult; D000368:Aged; D001259:Ataxia / Q000150:complications; D001369:Axons / Q000502:physiology*; D002648:Child; D003711:Demyelinating Diseases / Q000150:complications*; D004576:Electromyography; D005260:Female; D020275:Guillain-Barre Syndrome / Q000150:complications / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D019846:Miller Fisher Syndrome / Q000209:etiology* / Q000503:physiopathology*; D012016:Reference Values; D012021:Reflex, Abnormal