Myasthenia gravis is a neuromuscular disorder. Neuromuscular disorders involve the muscles and the nerves that control them.
Alternative Names
Neuromuscular disorder - myasthenia gravis
Causes
Myasthenia gravis is a type of autoimmune disorder. An autoimmune disorder occurs when the immune system mistakenly attacks healthy tissue. Antibodies are proteins made by the body's immune system when it detects harmful substances. Antibodies may be produced when the immune system mistakenly considers healthy tissue a harmful substance, such as in the case of myasthenia gravis. In people with myasthenia gravis, the body produces antibodies that block the muscle cells from receiving messages (neurotransmitters) from the nerve cells.
The exact cause of myasthenia gravis is unknown. In some cases, it is linked to tumors of the thymus (an organ of the immune system).
Myasthenia gravis can affect people at any age. It is most common in young women and older men.