title: Dysfunction at the motor end-plate and axon membrane in Guillain-Barré syndrome: a single-fiber EMG study.
abstract: In nine patients with Guillain-Barré syndrome (GBS), stimulation single-fiber electromyography (SFEMG) and serological studies were performed in the acute stage of the illness. Increased jitter and intermittent blocking of muscle fiber action potentials occurred to a varying degree in all patients. Five patients had elevated titers of antiganglioside antibodies. The most remarkable EMG phenomenon was the occurrence in all patients of impulse blocking at normal or slightly increased jitter. The assumption that this phenomenon was due to an axolemmal dysfunction was confirmed by the occurrence in two patients of concomitant blocking of two muscle fiber action potentials at strictly normal jitter values. In one patient this sign of axonal dysfunction was demonstrated with SFEMG at voluntary activation. In another patient, concomitant blocking was associated with greatly increased but completely independent jitter of both components. The results of this study show that both a disorder of neuromuscular transmission and an axolemmal dysfunction play a role in the pathophysiology of GBS.
authors.affiliation: Department of Clinical Neurophysiology, University Hospital, Postbox 5800, 6202 AZ Maastricht, The Netherlands. fsp@fknf.azm.nl
authors.forename: Frank
authors.initials: F
authors.lastname: Spaans
authors.forename: Jan-Willem
authors.initials: JW
authors.lastname: Vredeveld
authors.forename: Humphrey H E
authors.initials: HH
authors.lastname: Morré
authors.forename: Bart C
authors.initials: BC
authors.lastname: Jacobs
authors.forename: Marc H
authors.initials: MH
authors.lastname: De Baets
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000293:Adolescent; D000328:Adult; D000368:Aged; D001369:Axons / Q000502:physiology*; D002462:Cell Membrane / Q000502:physiology*; D004558:Electric Stimulation; D004576:Electromyography; D005260:Female; D005542:Forearm / Q000503:physiopathology; D020275:Guillain-Barre Syndrome / Q000276:immunology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009045:Motor Endplate / Q000503:physiopathology*; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000276:immunology / Q000503:physiopathology; D009431:Neural Conduction / Q000502:physiology; D009469:Neuromuscular Junction / Q000503:physiopathology