Generalized myasthenia gravis (gMG)
What is gMG?
Generalized myasthenia gravis (gMG) is a rare autoimmune disorder characterized by loss of muscle function and severe muscle weakness. gMG can occur at any age but it most commonly begins for women before the age of 40 and for men after the age of 60.1,2 It typically begins with weakness in the muscles that control the movements of the eyes and eyelids, and often progresses to the more severe symptoms such as weakness of the head, neck, trunk, limb and respiratory muscles.3-5 gMG impacts the neuromuscular junction (NMJ), which is the connection point between nerve cells and the muscles they control.6
Patients with gMG can suffer from slurred speech, choking, impaired swallowing, double or blurred vision, extreme fatigue, lack of balance and episodes of respiratory failure.4,5
80% of people with gMG are anti-acetylcholine receptor (AChR) antibody-positive.6 In patients with AChR+ MG, the body’s own immune system turns on itself to produce antibodies against AChR, a receptor that plays an important role in the communication between nerves and muscles.
The binding of these antibodies to AChR activates the complement cascade, causing the immune system to attack the NMJ. This leads to inflammation and a breakdown in communication between the brain and the muscles.6-8
gMG Symptoms
gMG symptoms include: 4,5
Blurred or double vision
Slurred speech
Lack of balance
Difficulty swallowing or choking
Extreme fatigue
Respiratory failure
It was a relief to have an answer. Now I knew why I was feeling what I was feeling, so we could make a plan."Liz
Living with gMG
References
- Jung-Plath W, et al. Assessment of myasthenia gravis patients quality of life. The Journal of Neurological and Neurosurgical Nursing. 2023;12(2):74-83
- Cavanagh N, et al. Exploring the impairments and allied health professional utilization in people with myasthenia gravis: a cross-sectional study. J Clin Neurosci. 2023;114:9-16.
- Sanders DB, Wolfe GI, Benatar M, et al. International consensus guidance for management of myasthenia gravis: executive summary. Neurology. 2016;87(4):419-425.
- Catalin J, et al. Clinical presentation of myasthenia gravis. Thymus. 2019.
- Farid ZR, et al. Factors affecting generalization of ocular myasthenia gravis. Sriwijaya Journal of Ophthalmology. 2020;3(2):48-54.
- Omar A, et al. Physiology, neuromuscular junction. StatPearls. 2023.
- Zhu Y, et al. Clinical features of myasthenia gravis with neurological and systemic autoimmune diseases. Front Immunol. 2023;14(14):1223322.
- Huang YF, et al. Visualization and characterization of complement activation in acetylcholine receptor antibody seropositive myasthenia gravis. Muscle Nerve. 2024.
Veeva ID: US/UNB-g/0731