Myasthenia gravis is an autoimmune condition of the neuromuscular system that’s characterized by impaired communication between the nerves and muscles. This condition leads to weakness in the skeletal muscles.
Multiple sclerosis (MS) is a chronic neurological condition that’s characterized by progressive nerve damage. The condition leads to decreased central nervous system communication and neurological symptoms.
In this article, we take a look at the similarities and differences between myasthenia gravis and MS.
|myasthenia gravis||multiple sclerosis|
|Causes||autoimmune condition in which the neuromuscular junction is attacked||immune-mediated condition in which the nerves within the central nervous system are attacked|
|Symptoms||primarily involves the skeletal muscles||can involve any system within the body, including the skeletal muscles|
|Demographics||often diagnosed from ages 40–60 and is equally prevalent across ethnicities and genders||primarily diagnosed from ages 20–50 and is more prevalent in people assigned female at birth and those of white European descent|
|Diagnosis||diagnosed through a physical exam, electromyography (EMG), and antibody testing||diagnosed through a physical exam, lumbar puncture, visual evoked potential (VEP) test, and imaging tests|
|Treatment||medication can help reduce immune response, while surgeries and procedures can help reduce chronic symptoms||disease-modifying therapies and other medications can help reduce chronic symptoms and relapses|
Myasthenia gravis causes
Myasthenia gravis is an autoimmune disorder. This is a disorder that occurs when the immune system mistakenly attacks the body.
In people with myasthenia gravis, the immune system attacks the neuromuscular junction, which is responsible for sending signals from the nerves to the muscle fibers. When this junction is damaged, it prevents the neurotransmitter acetylcholine from being able to transmit these signals, and the muscles can no longer contract properly.
Multiple sclerosis causes
MS is an immune-mediated condition with autoimmune features which, like myasthenia gravis, is caused by the body attacking itself.
In people with MS, the immune system attacks the central nervous system, including the:
- protective myelin around the nerves
- myelin-producing cells
When these nerves become damaged, they’re no longer able to effectively send or receive signals from the rest of the body, resulting in a variety of neurological symptoms.
Myasthenia gravis symptoms
Myasthenia gravis primarily causes muscle weakness that is often made worse by periods of exertion or activity. Sometimes, these symptoms can appear without warning and may be confused for other neurological conditions.
- blurry or double vision
- drooping eyelids
- eye muscle weakness
- facial paralysis
- shortness of breath
- speech impairment
- trouble swallowing or chewing
- weakness in the limbs or neck
In severe cases, weakness of the respiratory muscles can lead to complications such as respiratory failure.
Multiple sclerosis symptoms
Multiple sclerosis primarily causes neurological symptoms that can range in severity based on whether a person is in relapse or remission. Most of these differences depend on which stage of MS the person is in.
More common symptoms of MS include:
- bladder dysfunction
- bowel problems
- cognitive disturbances
- chronic pain sensations
- dizziness or vertigo
- emotional disturbances
- muscle spasticity or weakness
- numbness or tingling
- sexual dysfunction
- trouble walking
- vision disturbances
Other uncommon symptoms of MS may also include:
Myasthenia gravis demographics
Myasthenia gravis is
Multiple sclerosis demographics
Multiple sclerosis also affects people of all races and ethnicities. However, it is most common in people who are white and of European descent.
Most cases are diagnosed between the ages of 20 and 50, but children, teenagers, and older adults can also be diagnosed with the condition. MS is 3 times as common in females as it is in males.
Diagnosing myasthenia gravis
Myasthenia gravis is often misdiagnosed as a different neurological condition with similar symptoms, such as MS or ALS. With this in mind, the following tests may be used to determine if symptoms are due to myasthenia gravis or another condition:
- Physical exam. A physical examination generally includes a review of someone’s medical history and a full-body examination. A neurological exam can also be performed to look for abnormalities in muscle strength, muscle tone, and coordination.
- Specialized tests. An edrophonium test is used to check temporary muscle improvements in people with myasthenia gravis. Generally, this test is most beneficial for ocular myasthenia. Single-fiber electromyography (EMG) is the most sensitive test for myasthenia gravis because it measures if there is impairment between the nerves and muscles.
- Blood tests. A blood test can be used to check for either acetylcholine receptor antibodies or anti-MuSK antibodies, both of which can be present in myasthenia gravis.
- Imaging tests. Both CT scans and MRI scans may be used to check for the presence of any tumors that can be linked to myasthenia gravis.
Diagnosing multiple sclerosis
Multiple sclerosis is also a difficult disorder to diagnose because there’s no specific test for the condition. Instead, it is more likely to be diagnosed after other conditions have been ruled out using tests such as:
- Specialized tests. A lumbar puncture can be used to remove cerebrospinal fluid (CFS) from the spine, which can then be tested for certain antibodies, proteins, or other immune system cells. A visual evoked potential (VEP) test can be used to measure the electrical activity along the optic nerve pathway, which is often one of the first pathways affected in people with MS.
- Blood tests. A blood test can be used to help rule out any other conditions that may be causing the symptoms, such as HIV or AIDS, Lyme disease, or syphilis. In some cases, genetic testing can help determine if an underlying hereditary disorder is present.
- Imaging tests. An MRI can help look for other underlying conditions or indications of MS, which can include demyelination of the nerves or other scarring and inflammation consistent with MS.
Treating myasthenia gravis
Although there’s no cure for myasthenia gravis, treatment can help manage the long-term symptoms. Treatment options for this condition include:
- Medication. Certain medications, such as immunosuppressants and corticosteroids, can help suppress the immune system response that’s present in myasthenia gravis. Other medications, such as cholinesterase inhibitors, can help the nerves and muscles communicate better.
- Procedures and surgeries. Plasmapheresis, or plasma exchange, can help remove autoimmune antibodies from the blood and decrease muscle weakness. Intravenous immune globulin (IVIG) can also change the levels of antibodies in the blood. In some people with myasthenia gravis, the removal of the thymus gland — which helps produce antibodies — can help improve muscle strength.
Treating multiple sclerosis
Like myasthenia gravis, there’s no current cure for MS, but certain medications and other treatment options can help improve symptoms and reduce relapses. Treatment options for this condition include:
- Medication. Disease-modifying therapies (DMTs) are medications designed to help improve MS outcomes by reducing disease progression, relapses, and new damage. DMTs can be administered orally or via injection, and they include options such as Avonex, Betaseron, Tecfidera, and
Lemtrada. Other medication options are aimed at improving the symptoms of the disease, and can include corticosteroids, pain medications, antidepressants, and more.
- Lifestyle changes. Lifestyle changes can also help people with MS manage or reduce the symptoms of the disease. Getting enough sleep, engaging in gentle exercise, or even undergoing physiotherapy are all examples of activities that can help improve the quality of life for people with MS.
Myasthenia gravis and multiple sclerosis are both immune-mediated conditions that can cause a wide range of neurological symptoms. While the two conditions may seem similar, there are notable differences that distinguish them from one another.
Myasthenia gravis involves the neuromuscular junction, primarily affects the skeletal muscles, and is treated using medications and other procedures to help reduce immune system activation. MS involves the central nervous system, can affect the entire body, and is primarily treated using medications and lifestyle changes to reduce symptoms and relapses.
If you’ve been diagnosed with either of these conditions, receiving the proper diagnosis and getting the right treatment can help improve your overall quality of life.