Myasthenia Gravis (MG)

 

Overview

When nerve impulse transmission is interrupted at the neuromuscular junction where nerve cells and muscles connect, due to acetylcholine receptors being blocked or destroyed by antibodies. Acetylcholine receptors activate muscle contractions; thus, their destruction prevents those contractions from occurring.

Common Symptoms

Weakness of the extrinsic ocular muscles and include drooping of the eyelids, blurred or double vision, difficulty swallowing, shortness of breath, impaired speech, and weakness in the arms, hands, fingers, legs, and neck. MG can also lead to respiratory failure.

Coexisting Diseases and Conditions

Thyroiditis, rheumatoid arthritis, systemic lupus erythematosus, neuromyelitis optica spectrum disorder, and myocarditis.

Risk Factors and Prevalence

MG can occur at any age and can impact both males and females. Early-onset MG is diagnosed before age 50, and occurs more commonly in females, whereas late-onset MG (over 50 years) arises mainly in males.

Sources

  1. Article Sources and Footnotes

    1. Jayam Trouth, A., Dabi, A., Solieman, N., Kurukumbi, M., & Kalyanam, J. (2012). Myasthenia Gravis: A Review. Autoimmune Diseases, 2012, e874680. https://doi.org/10.1155/2012/874680
       

    2. Myasthenia Gravis Fact Sheet | National Institute of Neurological Disorders and Stroke. (n.d.). Retrieved July 9, 2021, from https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Myasthenia-Gravis-Fact-Sheet

    3. Sieb, J. P. (2014). Myasthenia gravis: An update for the clinician. Clinical & Experimental Immunology, 175(3), 408–418. https://doi.org/10.1111/cei.12217