Repetitive nerve stimulation of facial muscles in MuSK antibody-positive myasthenia gravis

Academic Article

Abstract

  • To better define electrophysiological abnormalities in myasthenia gravis (MG) patients with muscle-specific tyrosine kinase (MuSK) antibodies (Ab), we compared electrophysiological features of 14 MuSK Ab-positive, 73 acetylcholine receptor antibody (AChR Ab)-positive, and 22 MuSK and AChR Ab-negative (seronegative) patients with generalized disease. Repetitive nerve stimulation (RNS) abnormalities were observed in 86% of MuSK Ab-positive and 82% of AChR Ab-positive patients but in only 55% of seronegative patients. RNS decrements in the orbicularis oculi were more common and severe in the MuSK Ab-positive patients than the other two groups. Single-fiber electromyography (SFEMG) of the extensor digitorum communis was abnormal in 90% of MuSK Ab-positive patients. The high frequency of RNS abnormalities in facial muscles in the MuSK Ab-positive population reflects the propensity for facial muscle involvement in this form of MG and emphasizes the importance of including facial muscles in RNS protocols when evaluating these patients. © 2006 Wiley Periodicals, Inc.
  • Authors

    Published In

  • Muscle and Nerve  Journal
  • Digital Object Identifier (doi)

    Author List

  • Oh SJ; Hatanaka Y; Hemmi S; Young AM; Scheufele ML; Nations SP; Lu L; Claussen GC; Wolfe GI
  • Start Page

  • 500
  • End Page

  • 504
  • Volume

  • 33
  • Issue

  • 4