Clinical features of laryngeal myasthenia gravis: A case series

Am J Otolaryngol. 2019 Mar-Apr;40(2):292-296. doi: 10.1016/j.amjoto.2018.11.002. Epub 2018 Nov 5.

Abstract

Background: Myasthenia gravis (MG) is an autoimmune disease. Dysarthria, dysphagia, and difficulty swallowing as exclusive initial and primary complaints in MG (laryngeal MG) are rare and seldom reported.

Methods: Here we review and analyze the largest series of laryngeal MG patients.

Results: A total of 30 patients with laryngeal MG as primary manifestation were found in 20 case reports/series. Dysarthria was the most frequent primary symptom (14/30), followed by dysphagia (11/30), slurred speech (4/30) and dysphonia (1/30). Sixty-three percent visited the otolaryngology department first. Only 23.33% of patients were diagnosed with MG at the first clinic visit. Forty-five percent laryngeal MG patients were acetylcholine receptor (AChR) antibody positive, 52.9% showed decremental response in the repetitive nerve stimulation (RNS) test, and 92.6% were positive in the neostigmine/edrophonium test. Fluctuating weakness was examined in 16 of 30 patients and observed in 14/16 patients.

Conclusion: Laryngeal MG is a rare and possibly under-diagnosed condition. The patients can present with dysarthria, dysphagia, or difficulty swallowing. Fluctuation in severity of disease by neostigmine/edrophonium test is a typical feature for MG patients. AChR antibody and RNS tests should be included to evaluate the pathologic changes in the neuromuscular junction.

Keywords: Diagnosis; Dysarthria; Dysphagia; Laryngeal; Myasthenia gravis.

Publication types

  • Review

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Autoantibodies / blood
  • Biomarkers / blood
  • Child
  • Child, Preschool
  • Deglutition Disorders / etiology
  • Diagnostic Techniques, Neurological
  • Dysarthria / etiology
  • Dysphonia / etiology
  • Female
  • Humans
  • Laryngeal Diseases / complications
  • Laryngeal Diseases / diagnosis*
  • Laryngeal Diseases / physiopathology*
  • Male
  • Middle Aged
  • Myasthenia Gravis / complications
  • Myasthenia Gravis / diagnosis*
  • Myasthenia Gravis / physiopathology*
  • Receptors, Cholinergic / immunology
  • Speech Disorders / etiology
  • Young Adult

Substances

  • Autoantibodies
  • Biomarkers
  • Receptors, Cholinergic