J Neurol Neurosurg Psychiatry 76:1099-1102 doi:10.1136/jnnp.2004.052415
  • Paper

The features of myasthenia gravis with autoantibodies to MuSK

  1. D Lavrnic1,
  2. M Losen3,
  3. A Vujic1,
  4. M De Baets3,
  5. L J Hajdukovic4,
  6. V Stojanovic1,
  7. R Trikic1,
  8. P Djukic2,
  9. S Apostolski1
  1. 1The Institute of Neurology, Clinical Centre of Serbia, Belgrade, Serbia and Montenegro
  2. 2Institute of Cardiovascular Surgery, Clinical Centre of Serbia, Belgrade, Serbia and Montenegro
  3. 3Department of Cellular Neuroscience, Universiteit Maastricht, The Netherlands
  4. 4Institute for the Application of Nuclear Energy, Belgrade, Serbia and Montenegro
  1. Correspondence to:
 Dr D Lavrnic
 Institute of Neurology, Clinical Centre of Serbia, 11000 Belgrade, 6 Dr Subotica Street, Serbia and Montenegro; joltruthsezampro.yu
  • Received 22 August 2004
  • Accepted 16 December 2004
  • Revised 8 November 2004


Objectives: To determine if myasthenia gravis (MG) with antibodies to MuSK is a distinct subgroup of seronegative MG.

Methods: We assayed antibodies to muscle specific tyrosine kinase (MuSK) in 55 MG patients who had no antibodies to acetylcholine receptors and looked for the specific phenotype, comparing clinical features of anti-MuSK positive and anti-MuSK negative MG patients.

Results: MG with anti-MuSK antibodies was characterised by a striking prevalence of female patients (15 women, two men). Age at onset ranged from 22 to 52 years, with 70.6% of patients presenting at <40 years of age. The majority of patients (82.4%) had prevalent involvement of facial and bulbar muscles. One third of them did not respond well to anticholinesterase drugs. Steroid immunosuppression was effective in eight patients (44.4%). Nine patients underwent thymectomy; six of these had no thymus pathology, while three had a hyperplastic thymus. At the end of the observation period, six (35.3%) patients were in remission, five (29.4%) improved, four (23.6%) did not change, and two (11.7%) had died.

Conclusions: MG patients with antibodies to MuSK have characteristic clinical features that are different from features of the remaining seronegative MG patients. This emphasises the predictive value of anti-MuSK antibody analysis in seronegative MG patients.


  • Competing interests: none declared

Visit the full archive of podcasts for JNNP here >>

Free sample
This recent issue is free to all users to allow everyone the opportunity to see the full scope and typical content of JNNP.
View free sample issue >>

Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.

Navigate This Article