Myasthenia Gravis - Symptoms and Treatment

Myasthenia gravis is a chronic autoimmune neuromuscular disease characterized by varying degrees of weakness of the skeletal (voluntary) muscles of the body. Skeletal muscles are primarily muscle fibers that contain bands or striations that are connected to bone. Myasthenia gravis causes rapid fatigue and loss of strength upon exertion that improves after rest. MG most commonly occurs in young adult women and older men but can occur at any age. Although MG may affect any voluntary muscle, certain muscles including those that control eye movements, eye lids, chewing, swallowing, coughing, and facial expressions are more often affected. Weakness may also occur in the muscles that control breathing and arm and leg movements.

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 first noticeable symptoms of myasthenia gravis may be weakness of the eye muscles, difficulty in swallowing, or slurred speech.

Symptoms vary in type and severity. Myasthenia gravis is not directly inherited nor is it contagious. The first steps in diagnosing myasthenia gravis include a review of the individual's medical history and physical and neurological examinations. If the doctor suspects myasthenia gravis, several diagnostic tests are available to confirm the diagnosis, including a special blood test that can detect the presence of immune molecules or acetylcholine receptor antibodies.

Myasthenia gravis is an autoimmune disease that affects the transmission of signals from nerves to muscles. The name myasthenia gravis, which is Latin and Greek in origin, literally means "grave muscle weakness. "Today, however, most cases of myasthenia gravis are not as "grave" as the name implies. In fact, for the majority of individuals with myasthenia gravis, life expectancy is not lessened by the disorder. Common symptoms are trouble with eye and eyelid movement, facial expression and swallowing. If you have myasthenia gravis, it is important to follow your treatment plan. If you do, you can expect your life to be normal or close to it.

Myasthenia gravis is caused by a problem in the transmission of nerve signals to your muscles. Normally, nerve endings release a substance that attaches to receptors on your muscles. That tells your muscles to contract. If you have myasthenia gravis, your body's own immune system makes antibodies to block that signal. Medicine can help improve nerve-to-muscle messages and make muscles stronger. Other medicines can keep your body from making so many abnormal antibodies. Sometimes surgery to take out the thymus gland helps.

Causes of Myasthenia Gravis

Find common causes and risk factors of Myasthenia Gravis:

Myasthenia Gravis is caused by a defect in the transmission of nerve signals to muscles. It occurs when normal communication between the nerve and muscle is interrupted at the neuromuscular junction - the place where nerve cells connect with the muscles they control. Normally when impulses travel down the nerve, the nerve endings release a neurotransmitter substance called acetylcholine. Acetylcholine travels through the neuromuscular junction and binds to acetylcholine receptors which are activated and generate a muscle contraction. In myasthenia gravis, antibodies block, alter, or destroy the receptors for acetylcholine at the neuromuscular junction which prevents the muscle contraction from occurring. These antibodies are produced by the body's own immune system. Thus, myasthenia gravis is an autoimmune disease because the immune system - which normally protects the body from foreign organisms - mistakenly attacks itself.

Signs and Symptoms of Myasthenia Gravis

Sign and symptoms may include the following :

• Double vision.
• Muscle weakness in your arms or legs .
• Fatigue brought on by repetitive motions.
• Difficulty in breathing, talking, chewing or swallowing.
• Weakness of muscles including those of the face.

Treatment for Myasthenia Gravis

MG can be treated and is completely curable. Treatment may involve surgery on the thymus gland if it has a tumor. Drugs that prolong the action of acetylcholine, and steroids are used in the treatment of Myasthenia Gravis. Other therapies include plasmapheresis, a procedure in which abnormal antibodies are removed from the blood, and high-dose intravenous immune globulin, which temporarily modifies the immune system and provides the body with normal antibodies from donated blood.

Treatment may include:

• Anticholinesterase medications, such as Prostigmin or Tensilon; steroids; and/or immunosuppressive (suppress the immune system's response) medications may be used.
• A blood product that helps to decrease the immune system's attack on the nervous system, given intravenously (IV).
• A procedure that removes abnormal antibodies from the blood and replaces the blood with normal antibodies through donated blood.
• Surgical removal of the thymus gland (helps rebalance the immune system).
• Plasma exchange (plasmapheresis), in which the person's blood plasma containing the abnormal antibodies is removed and fresh plasma is put back .
• Corticosteroid medications such as prednisone.
• Medications that suppress the immune system, such as Imuran (azathioprine) and cyclosporine.