Myasthenia Gravis - Symptoms & Treatment

Myasthenia gravis is a chronic disorder characterized by weakness and rapid fatigue of any of the muscles under your volitional control. The muscle weakness increases during periods of activity and meliorates after periods of rest. MG often involves muscles which regulate eye and eyelid movement, facial expression, chewing, talking, and swallowing. Less often, the muscles involved in breathing may be affected. MG affects about one person in every 10,000 in the UK. It can develop at any age, but is most common in women under the age of 40 and men over the age of 60. Weakness is typically caused by circulating antibodies which shroud acetylcholine receptors at the post-synaptic neuromuscular junction, inhibiting the stimulative effect of the neurotransmitter acetylcholine. A myasthenic extremity may give rise to a generalized paralysis and assisted ventilation may be required to sustain life. Acetylcholine is a chemical substance which endures muscle contraction by stimulating the muscle fibers by binding to its receptors. The immunologic reaction against these receptors and successive damage of the neuromuscular endplate give rise to deficient stimulation of muscle fibers. Patients frequently present with circumscribed movements of eye muscles and eyelids, difficulty swallowing and speaking, generalized weakness and fatigue. Myasthenia gravis is usually treated with cholinesterase inhibitors, immunosuppressive drugs, thymectomy and plasma interchange. Though the term gravis means grave, recent developments in disease treatment have made the prognosis more opportune. Nonetheless a considerable portion of patients still find it necessary to seek admission to the intensive care units for assisted ventilation.

Myasthenia Gravis (MG) is a chronic autoimmune disorder which inhibits neuromuscular transmissions by blocking the acetylcholine receptors with autoantibodies. The name myasthenia gravis, that is Latin and Greek in genesis, literally means "grave muscle weakness." With current therapies, however, most cases of myasthenia gravis are not as "grave" as the name insinuates. In fact, for the majority of individuals with myasthenia gravis, life anticipation is not lessened by the disorder.

Causes of Myasthenia Gravis

Common causes and risk factor's of Myasthenia Gravis include the following :

• Systemic lupus erythematosus .
• Thyrotoxicosis.
• Rheumatoid arthritis.

Symptoms of Myasthenia Gravis

Some common Symptoms of Myasthenia Gravis :

• Double vision.
• Slurred speech.
• Difficulty chewing and swallowing.
• Weakness in arms and legs.
• Facial muscle weakness, including drooping eyelids.
• Shortness of breath.

Treatment of Myasthenia Gravis

• A blood product which helps to reduce the immune system's attack on the nervous system, offered intravenously (IV).
• Anticholinesterase medications, such as Prostigmin or Tensilon; steroids; and/or immunosuppressive (suppress the immune system's response) medications may be used.
• A procedure which removes abnormal antibodies from the blood and replaces the blood with normal antibodies through donated blood.
• Surgical removal of the thymus gland. The role of the thymus gland in MG is not fully understood, and the thymectomy may or may not improve a child's symptoms.