The first descriptions of Myasthenia Gravis, (MG) cases occurred more than 300 years ago, yet it was not until a series of discoveries in the mid 1970s that an understanding of and general consensus that MG symptoms are due to an autoimmune response impacting neuromuscular functions developed. The distinctive feature of MG is fluctuating muscle weakness, made worse by use of those muscles and improved at least partially by resting them. The muscles affected are called voluntary muscles … muscles that we use all the time, such as those used to move the eyes or hold the eyelids open. The muscles used for facial expressions, chewing, talking or swallowing can be selectively affected. MG can affect neck muscles holding up the head which can go into spasm because they are weak. Muscles affecting the limbs can prevent a person from accomplishing activities of daily living such as holding up an arm to comb hair, shave, shampoo or put on make-up. Getting out of the bathtub or up from a sofa, climbing stairs or walking distances may be impaired. We take these muscles for granted until they don’t work as expected.

With MG, the body’s immune system mistakenly attacks and destroys its own special proteins (acetylcholine receptors) located on the muscle surface where a nerve meets the muscle. If some acetylcholine receptors are destroyed the muscle response is reduced and weakness occurs.

The seriousness of MG is particularly noticeable when some muscles that we use in breathing are affected. If the ability to breathe becomes insufficient, the patient is said to be in a “Myasthenic crisis” and mechanical breathing assistance in a hospital may be necessary. Different muscle groups are affected from patient to patient and some only have Ocular Myasthenia involving the eye muscles. Although MG can be fatal if a respiratory crisis is not treated immediately, with proper treatment, normal life expectancy is the rule.

Myasthenia Gravis means “grave weakness”. It can affect people of all racial and ethnic groups and in both sexes, from infancy to old age. It is not uncommon for family members to have the same or different autoimmune diseases and some individuals can have more than one autoimmune condition. The prevalence rate of patients with MG is estimated to be 1 in 5,000, but because MG is often misdiagnosed, the rate may be higher. At present, the cause of MG is unknown and there is no cure.

Similar to other chronic diseases, treatment can be complex, debilitating and expensive. Potent medications and intravenous immune globulin (IVIG) and plasmapheresis, which are dispensed in a drip method through a vein, can provide side effects in themselves. Because the thymus glad is an organ involved in the development of the immune system, removal is often recommended for patients diagnosed with MG. The operation is called a thymectomy and although there may be a lessening of symptoms and reduction of MG-related drugs, there are risks with surgery and relapse is possible. As always, patients must become their own health care advocate in order to deal with insurance companies, pharmacies, physicians and other allied health professionals.