Myasthenia gravis (MG) is a chronic, complex, autoimmune disorder in which antibodies destroy neuromuscular connections. The hallmark of myasthenia gravis is muscle weakness that increases during periods of activity and improves after periods of rest. Muscles that control eye and eyelid movements, facial expression, chewing, talking, and swallowing are often, but not always, involved. The muscles that control breathing and neck and limb movements may also be affected. Myasthenia gravis is caused by a defect in the transmission of nerve impulses to muscles. Normally when impulses travel down the nerve, the nerve endings release a neurotransmitter substance called acetylcholine. In myasthenia gravis, antibodies produced by the body’s own immune system block, alter, or destroy the receptors for acetylcholine.
The diagnosis of myasthenia gravis involves an extensive physical exam and diagnostic testing. The most common symptoms include problems in vision such as drooping eyelids (ptosis) and double vision (diplopia), severe muscle weakness and fatigue, facial muscle involvement causing a mask-like appearance, difficulty in swallowing and/or pronouncing words, weakness of the neck and/or limbs.During the physical examination, the doctor will ask for a complete medical history, and may also ask if there is a family history of any medical problems.A primary characteristic of MG results in the response of an affected person to certain medications. When given an anticholinesterase medication, such as neostigmine (prostigmin) or edrophonium (Tensilon), muscle weakness often dramatically improves for a brief time. This provides strong support for the diagnosis of MG.
Myasthenia gravis is a lifelong medical condition and the key to medically managing MG is early detection and timely treatment that may help relieve signs and symptoms. Specific treatment for myasthenia gravis will be determined by your doctor based on factors such as age, overall health, medical history, extent of the condition, tolerance for specific medications, procedures, or therapies, expectations for the course of the condition and your preference.
The goal of treatment is to increase general muscle function and prevent secondary respiratory and nutritional problems since the swallowing and breathing muscles are affected by this condition. Most people with MG can improve their muscle strength and lead normal or near normal lives. In more severe cases, respiratory or nutritional support may be required due to breathing or swallowing difficulty.Treatment may includemedications, thymectomy or the surgical removal of the thymus gland, plasmapheresis which involves the removal of abnormal antibodies from the blood and replacement with donor blood having normal antibodies.
Since timely detection is the key to treatment of myasthenia gravis, doctors at GIN use the most advanced of technologies and procedures currently available to diagnose the disease and mitigate its symptoms.
The following tests may be performed to help confirm the diagnosis of myasthenia gravis:
- Blood tests: These tests look for antibodies that may be present in people with myasthenia gravis.
- Genetic tests: Diagnostic tests that evaluate for conditions that have a tendency to run in families.
- Electromyogram (EMG):This measures the electrical activity of a muscle or a group of muscles. An EMG can detect abnormal electrical muscle activity due to diseases and neuromuscular conditions.