MuSK-antibody positive myasthenia gravis: clinical and electrodiagnostic patterns.

Journal Article (Journal Article)

OBJECTIVE: To examine the clinical manifestations and patterns of electromyographic abnormalities in MuSK-Ab positive myasthenia gravis. METHODS: The clinical evaluations and electrodiagnostic testing results of 20 MuSK-Ab positive myasthenia gravis patients were retrospectively reviewed and compared with matched AChR-Ab positive (N = 72) and MuSK-Ab negative/AChR-Ab negative (N = 24) patients. RESULTS: MuSK-Ab positive patients were younger and more frequently female and African-American, and compared to the AChR-Ab positive patients, were more likely to present with respiratory symptoms or neck extension weakness. MuSK-Ab positive patients were less likely to have abnormal jitter in a limb muscle: only 59% had abnormal jitter in the extensor digitorum communis muscle, compared to 80% of the AChR-Ab negative/MuSK-negative patients and 91% of the AChR-Ab positive patients. CONCLUSIONS: Our MuSK-Ab positive patients not only differ demographically from our MuSK-Ab negative cohort, but they also appear to have a more limited distribution of SFEMG abnormalities. SIGNIFICANCE: The possibility that electrophysiologic abnormalities may not be widely distributed should be considered during electrodiagnostic evaluation of suspected MuSK-Ab positive MG and in selecting muscles for molecular, morphologic, or microphysiologic studies in this condition.

Full Text

Duke Authors

Cited Authors

  • Stickler, DE; Massey, JM; Sanders, DB

Published Date

  • September 2005

Published In

Volume / Issue

  • 116 / 9

Start / End Page

  • 2065 - 2068

PubMed ID

  • 16043398

International Standard Serial Number (ISSN)

  • 1388-2457

Digital Object Identifier (DOI)

  • 10.1016/j.clinph.2005.06.003


  • eng

Conference Location

  • Netherlands