Different characteristic phenotypes according to antibody in myasthenia gravis

Academic Article


  • OBJECTIVES: To find the characteristic phenotypes of 3 different types of myasthenia gravis (MG). METHODS: The clinical and electrophysiological features among 15 cases of muscle-specific kinase antibody positive (MuSK Ab+) MG, 59 cases of double seronegative (DSN) MG, and 161 cases of acetylcholine receptor antibody (AChR Ab)+ MG in the University of Alabama at Birmingham were compared. RESULTS: AChR Ab was positive in 69% of cases and MuSK Ab in 6% of cases. MuSK Ab+ MG was more common (14%) in African Americans compared with whites (4%). AChR Ab+ MG is characterized by male predominance, later onset, a fewer cases of ocular MG, and a higher association with thymoma. DSN-MG is characterized by a greater prevalence of ocular MG, milder forms of MG with less number of crisis, and fewer abnormalities in the repetitive nerve stimulation test. MuSK Ab+ MG is characterized by younger age at onset, severe and bulbar forms of MG, predominant faciobulbar neck weakness, and a poor response to edrophonium, anticholinesterase, and intravenous immunoglobulin. Long-term outcome showed no difference among 3 types of MG. CONCLUSIONS: AChR Ab+ MG and DSN-MG are similar, with the exception of less severity in the latter. MuSK Ab+ MG has distinct clinical and electrophysiological features. Copyright © 2012 by Lippincott Williams & Wilkins.
  • Authors

    Digital Object Identifier (doi)

    Author List

  • Oh SJ; Morgan MB; Lu L; Hatanaka Y; Hemmi S; Young A; Claussen GC
  • Start Page

  • 57
  • End Page

  • 65
  • Volume

  • 14
  • Issue

  • 2