Myasthenia Gravis (MG) is a rare autoimmune* neuromuscular** disorder characterized by muscle weakness or muscle fatigue that is caused by a breakdown in the communication between the nerves and muscles. MG can occur at any age but is most commonly found in woman younger than 40 and men older than 60.
The main symptom of MG is muscle weakness that progressively gets worse in the affected muscles as they are used over time. Although myasthenia gravis can affect any of the muscles that you control voluntarily, the following muscle groups are more commonly affected:
Eye Muscles
More than half of people who develop myasthenia gravis, the first signs and symptoms involve eye problems, such as:
- Drooping of one or both eyelids (ptosis)
- Double vision (diplopia)
Face and throat muscles
In about 15% of people with myasthenia gravis, the first symptoms involve face and throat muscles, which can:
- Impair speech causing it to sound soft or nasal, depending on which muscles have been affected.
- Difficulty swallowing that may cause someone to choke easily, making it difficult to eat, drink or take pills.
- Affect chewing muscles to wear out or weaken halfway through a meal.
- Alter facial expressions making, for example, your smile to look like a snarl.
Neck and limb muscles
Myasthenia gravis can also affect your neck, arms and legs causing weakness in your legs affecting how you walk, and weakness in neck causing difficulty to hold up head.
At this time there is no cure for Myasthenia Gravis but using a combination of therapies can help relieve signs and symptoms, such as weakness of arm or leg muscles, double vision, drooping eyelids, and difficulties with speech, chewing, swallowing, and breathing.
After a thorough physical evaluation and diagnostic tests such as:
- Electromyogram (EMG): This test measures the electrical activity of muscles.
- Nerve conduction studies: A nerve conduction velocity test measures the nerves’ ability to send electrical signals. This test is often performed along with an EMG to help determine whether symptoms are related to your nerves or muscles.
- Electrodiagnostics: With the use of small electrical impulses along your arm, leg, or face to measure the muscle reaction.
A diagnoses and treatment plan will be created to address symptoms and concerns.
Your treatment plan may include:
- A Medication treatment plan determined by your physician focusing on your disorder. Some medications relieve your symptoms by reducing the antibodies in your body, while others (called immunosuppressants) aim to slow down the body’s immune system.
- Plasmapheresis which is a therapy, also called plasma exchange, filters your blood through a machine that removes harmful antibodies (similar to dialysis).
- Immunoglobulin therapy where the body receives an injection of high doses of good antibodies from healthy donor blood. These new antibodies help block the antibodies that may be attacking your nervous system.
It’s important to contact your doctor if you are having the following symptoms for proper diagnosis and treatment:
- Breathing
- Seeing
- Swallowing
- Chewing
- Walking
- Using your arms or hands
- Holding up your head
*Autoimmune: An illness that occurs when the body tissues are attacked by its own immune system. The immune system is a complex
**Neuromuscular: Of, relating to, or affecting both nerves and muscles.
Myasthenia Gravis | Symptoms and causes – Mayo Clinic
Myasthenia Gravis | Allegheny Health Network (ahn.org)