Myasthenia Gravis causes weakness and rapid fatigue of the muscles that are under voluntary control in the body. This condition is caused by a communication problem between the nerves and the muscles. There isn’t a cure for this condition, but there are treatments that can make the symptoms more manageable and which can improve the quality of life for those who suffer from the condition.
This condition can cause a range of symptoms depending upon which muscles are affected. Often symptoms are mild at first and become progressively worse over time.
The most common early symptoms of Myasthenia Gravis are symptoms that impact the eyes. Many people will experience drooping of one or both eyelids or have double vision that improves when they close one eye.
Face and throat muscles can also be impacted in about 15% of Myasthenia Gravis cases. The symptoms associated with throat impairment are difficulty swallowing, impaired speaking, problems with chewing, and changes to facial expressions.
The neck and the limbs can also be impacted and can feel weak, heavy, or uncoordinated. Over time, patients will begin to experience some combination of all of these symptoms together, which can lead to more serious complications like an inability to breathe, walk, or talk.
The cause of Myasthenia Gravis is an issue with the neurotransmitters at the nerve/muscle junction. When the immune system produces antibodies in those with Myasthenia Gravis, the receptor sites have been blocked or destroyed. This means that muscles are weaker since they have fewer receptor sites available for this communication. Antibodies can also attack the proteins that allow muscle function, causing advanced weakness related to this condition.
Some patients also have tumours of the thymus gland, which is responsible for producing acetylcholine which allows nerve function to happen correctly in the body. These tumours are typically not cancerous but can cause widespread nerve function issues in the body. In rare cases, this condition can be congenital.
The risk factors for Myasthenia Gravis are:
A neurological examination is key to getting a correct diagnosis for Myasthenia Gravis. These tests evaluate the reflexes, muscle strength and tone, and sensory responses to touch and sight. Your coordination and balance might also be tested.
The ice pack test is used to see if droopy eyelids improve after a bag filled with ice is placed on the eyelid. There are also blood analysis tests that can be done to look for missing antibodies in the blood that are linked with Myasthenia Gravis expression.
Nerve stimulation tests and single-fibre electromyography can also be used to test nerve function in the body. If the patient is struggling with breathing properly, pulmonary tests will likely be done, and imaging can be conducted to ensure that there are no tumours in the body that might be impacting nerve function or creating symptoms that look like Myasthenia Gravis.
This condition typically cannot be prevented. You might have the genetic markers to experience symptoms related to this condition but be symptom-free. The mechanism by which this disease becomes active is not yet fully understood.
Treatment often involves a combination of factors. Many patients will need to take corticosteroids to help control inflammation and help inhibit the immune system reactions that lead to the weakening of the muscles. Cholinesterase inhibitors can also help to provide support for and enhancement of the communication between nerves and muscles in the body.
Immunosuppressant drugs are also sometimes given to patients with this condition to help keep the immune reaction in check, which is leading to damage of the neurotransmitters that allow successful nerve function.