Tell your doctor about any medications or supplements you take. Some drugs can make MG symptoms worse. One of the most dangerous potential complications of MG is myasthenic crisis. This consists of life-threatening muscle weakness that can include breathing problems. Talk with your doctor about your risks. If you start to have trouble breathing or swallowing, call or go to your local emergency room immediately.
Individuals with MG are at a higher risk of developing other autoimmune disorders such as lupus and rheumatoid arthritis. The long-term outlook for MG depends on a lot of factors. Some people will only have mild symptoms. Others may eventually become confined to a wheelchair.
Talk to your doctor about what you can do to minimize the severity of your MG. Early and proper treatment can limit disease progression in many people. The vagus nerve is the longest of the 12 cranial nerves.
Here, learn about its anatomy, functions, and the kinds of health problems that can occur. Muscle twitching refers to small muscle contractions in the body. Learn more about the causes and treatment here. Parosmia is term used to describe health conditions that distort your sense of smell.
If you have parosmia, you may experience a loss of scent…. Abnormal posturing refers to rigid body movements and chronic abnormal positions of the body.
Learn more here. Many people find they're worse towards the end of the day, and better the next morning after getting some sleep.
Read more about the symptoms of myasthenia gravis. See a GP if you have long-lasting or worrying symptoms that could be caused by myasthenia gravis. The GP may refer you to a specialist for tests to help diagnose myasthenia gravis or look for other possible causes of your symptoms.
Tests you may have include a blood test , a test to see how well your nerves are working, and some scans, such as a CT scan or MRI scan. Read more about tests for myasthenia gravis. If the symptoms suddenly get worse — for example, you develop severe breathing or swallowing difficulties — you may need urgent treatment in hospital. Read more about how myasthenia gravis is treated.
At the normal neuromuscular junction, a nerve cell causes a muscle cell to contract by releasing the chemical acetylcholine ACh. ACh attaches to the ACh receptor — a pore or "channel" in the surface of the muscle cell — twisting it open and allowing an inward flux of electrical current that triggers muscle contraction.
These contractions enable someone to move a hand, to dial the telephone, to walk through a door, or to complete any other voluntary movement. Some treatments block acetylcholinesterase AChE , an enzyme that breaks down ACh, while others target the immune system. The antibodies Y-shaped protein that immune cells, called B cells, use to attack bacteria and viruses target and destroy many of the AChRs on muscle.
Scientists do not know what triggers most autoimmune reactions, but they have a few theories. One possibility is that certain viral or bacterial proteins mimic "self-proteins" in the body such as the AChR , stimulating the immune system to unwittingly attack the self-protein.
There's also evidence that an immune system gland called the thymus plays a role in MG see illustration below. Neurotransmitters are chemicals that neurons, or brain cells, use to communicate information. Normally when electrical signals or impulses travel down a motor nerve, the nerve endings release a neurotransmitter called acetylcholine that binds to sites called acetylcholine receptors on the muscle.
The binding of acetylcholine to its receptor activates the muscle and causes a muscle contraction. This is most often caused by antibodies to the acetylcholine receptor itself, but antibodies to other proteins, such as MuSK Muscle-Specific Kinase protein, also can impair transmission at the neuromuscular junction.
The thymus gland controls immune function and may be associated with myasthenia gravis. It grows gradually until puberty, and then gets smaller and is replaced by fat. Throughout childhood, the thymus plays an important role in the development of the immune system because it is responsible for producing T-lymphocytes or T cells, a specific type of white blood cell that protects the body from viruses and infections.
In many adults with myasthenia gravis, the thymus gland remains large. People with the disease typically have clusters of immune cells in their thymus gland and may develop thymomas tumors of the thymus gland. Thymomas are most often harmless, but they can become cancerous.
Scientists believe the thymus gland may give incorrect instructions to developing immune cells, ultimately causing the immune system to attack its own cells and tissues and produce acetylcholine receptor antibodies—setting the stage for the attack on neuromuscular transmission.
Myasthenia gravis affects both men and women and occurs across all racial and ethnic groups. It most commonly impacts young adult women under 40 and older men over 60 , but it can occur at any age, including childhood.
Myasthenia gravis is not inherited nor is it contagious. Occasionally, the disease may occur in more than one member of the same family..
Although myasthenia gravis is rarely seen in infants, the fetus may acquire antibodies from a mother affected with myasthenia gravis—a condition called neonatal myasthenia. Rarely, children of a healthy mother may develop congenital myasthenia.
This is not an autoimmune disorder but is caused by defective genes that produce abnormal proteins in the neuromuscular junction and can cause similar symptoms to myasthenia gravis.
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