What Is Myasthenia Gravis?
Myasthenia Gravis (MG) is a chronic autoimmune disorder, in which the patient’s antibodies destroy the communication between nerves and muscles and result in weakness of the skeletal muscles. The condition affects the body’s voluntary muscles, especially those that control the eyes, throat, mouth, and limbs. Although the exact cause of myasthenia gravis is not clear, the condition could involve a combination of factors, including genetics.
Let us read further to learn about myasthenia gravis is hereditary, along with risk factors that trigger the condition, the life expectancy of people with MG, diagnosis, and treatments for the condition.
Is Myasthenia Gravis Hereditary?
No, myasthenia gravis is not considered to be hereditary. According to the advocacy group Conquer Myasthenia Gravis, it has been mentioned that it is quite rare for more than one family member to suffer from myasthenia gravis.(1)
Myasthenia gravis is an autoimmune disease, and it is not unusual for several members of a family to have an autoimmune disease condition, even if they all do not have the same condition. So, genetics may play a major role in the development of myasthenia gravis, and researchers have been taking a closer look into whether there could be higher rates of this autoimmune condition within families.
A study conducted in 2020, which involved more than 1, 000 individuals with a specific type of myasthenia gravis has shown that the rate of MG within families was higher than what would be expected of any random disease. It was also found that a certain number of participants with the condition had a personal or family history of autoimmune disease.
These findings suggest that genetics play a specific role in the development of myasthenia gravis. More research is required to completely understand the potential link between genetics and the development of myasthenia gravis.
What Is Transient Neonatal Myasthenia Gravis?
Transient neonatal myasthenia gravis is a temporary form of myasthenia gravis that mothers can pass on to their newborns. However, this lasts only for a few days to a few weeks.
What is Congenital Myasthenia Syndrome?
Congenital myasthenia syndrome is another condition that exists. However, it is not an autoimmune condition, but an inherited genetic disorder.
What Are the Symptoms Associated With Myasthenia Gravis?
Common symptoms associated with myasthenia gravis include:
- Experiencing ptosis or drooping of one or both eyelids.
- Weakness of the eye muscles, also known as ocular myasthenia.
- Double or blurred vision.
- Changes in facial expressions.
- Impaired speech or dysarthria
- Shortness of breath.
- Difficulty swallowing.
- Weakness in the hands, arms, fingers, neck, and legs.
What is Myasthenic Crisis?
Sometimes the muscles that control breathing weaken and the affected person needs a ventilator to breathe. This is known as a myasthenic crisis and requires emergency medical attention. Infection, surgery, stress, or any adverse reaction to medication can trigger a myasthenic crisis.
Who is More Likely To Get Myasthenia Gravis?
Anyone can develop myasthenia gravis. However, it is more often seen in young women (20 to 30 years of age) and men (50 years and above). As per the Genetic and Rare Diseases Information Center, the average age at which women notice symptoms of MG is 28 years and men notice symptoms is 42 years.(3) Apart from this, people also tend to develop myasthenia gravis after suffering from an illness or infection.
One could be at a higher risk of myasthenia gravis if:
- They suffer from another autoimmune disease.
- They have family members with autoimmune diseases.
- They have abnormal thymus glands.
What Triggers Myasthenia Gravis?
Being an autoimmune disorder, myasthenia gravis happens when our body’s immune system mistakenly attacks healthy parts of the body. In the case of myasthenia gravis, it involves the creation of antibodies that interfere with signals between nerve cells and muscles.
This autoimmune disorder might also be linked with abnormalities of the thymus gland, and it occurs in around 75% of individuals having MG.(4)
Some other triggers that worsen the symptoms of myasthenia gravis include fatigue, lack of sleep, overexertion, anxiety, stress, depression, illness or infection, bright lights and sunlight, extreme temperature, and humidity, intake of alcohol, low potassium levels, abnormal thyroid levels, exposure to specific chemicals.
In addition to this, certain medications can also trigger myasthenia gravis. These medications are antibiotics, Botox, beta-blockers, calcium channel blockers, magnesium, muscle relaxants, lithium, and verapamil.
How is Myasthenia Gravis Diagnosed?
Several tests can confirm a diagnosis of myasthenia gravis. Some of these include:
Physical and Neurological Examination
The doctor reviews your medical history and performs a physical examination. In a neurological examination, the doctor checks muscle strength and tone, sense of touch, eye coordination, and eye movements.
Electrodiagnostics
Diagnostic tests for myasthenia gravis include:
- Repetitive Nerve Stimulation: It uses small pulses of electricity to stimulate the nerves and the physician tests the electrical responses of the muscles that receive those stimuli.
- Single Fiber Electromyography (EMG): It is a sensitive test for myasthenia gravis that detects impaired nerve-to-muscle transmission. This is essential in diagnosing mild cases of myasthenia gravis.
Blood Test
Individuals with myasthenia gravis typically have significantly elevated levels of acetylcholine receptor antibodies or anti-MuSk antibodies. A blood test can detect these antibodies. However, in some people with MG, neither of these antibodies is present. This is known as seronegative myasthenia.
What Are The Treatment Options For Myasthenia Gravis?
Medication, surgery, and other therapies are various ways to treat myasthenia gravis. Some of the treatment methods for myasthenia gravis include:
- Anticholinesterase medications
- Monoclonal antibody treatment
- Immunosuppressive drugs
- Intravenous immunoglobulin therapy (IVIG)
- Plasma exchange
- Thymectomy
Apart from all these treatment approaches, self-care is one of the most important ways to improve symptoms of myasthenia gravis. Below are some self-care techniques to get over myasthenia gravis.
- Rest your eyes and take naps whenever required.
- Have a good full night’s sleep.
- Get physically active when you have high energy levels.
- Avoid extreme temperatures.
- Incorporate nutritious foods into your daily diet.
- Visit your doctor regularly and take prescribed medications.
What is The Life Expectancy of Persons With Myasthenia Gravis?
Usually, most people with myasthenia gravis have an average outlook, with no drops in life expectancy. However, treatment at the right time is plays a significant role. Treatments can help in minimizing the severity of symptoms in cases of myasthenia gravis.
Some affected individuals have surgery to remove their abnormal thymus gland, known as a thymectomy.
According to the National Institute of Neurological Disorders and Stroke, it has been mentioned that about half of them experience long-term remission.(5) Some people who undergo that treatment might also be able to stop taking medications for MG at some point.
Conclusion
Myasthenia gravis is not a heriditary disease. However, a genetic component can be involved in the development of this condition. Anyone can have myasthenia gravis at any point in time, though it is more likely to occur after an illness or infection.
Being an autoimmune disorder that runs in families, your risk of developing myasthenia gravis can be higher if you or others in your family have another autoimmune condition. Talk to your doctor about the appropriate diagnosis and treatment for your condition.
- https://www.myastheniagravis.org/about-mg/mg-faq/
- https://bmjopen.bmj.com/content/10/9/e037909
- https://rarediseases.info.nih.gov/diseases/7122/myasthenia-gravis
- https://rarediseases.org/rare-diseases/myasthenia-gravis/
- https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Myasthenia-Gravis-Fact-Sheet
Also Read:
- Myasthenia Gravis: Causes, Signs, Symptoms, Investigations, Treatment- Medications, Surgery
- How Do You Get Myasthenia Gravis?
- Can Myasthenia Gravis Go Away On Its Own?
- Recovery Period For Myasthenia Gravis
- Can I Drive With Myasthenia Gravis?
- What Is The Best Treatment For Myasthenia Gravis?
- Does Myasthenia Gravis Cause Blindness?