With treatment, most individuals with myasthenia can significantly improve their muscle weakness and lead normal or nearly normal lives. Some cases of myasthenia gravis may go into remission—either temporarily or permanently—and muscle weakness may disappear completely so that medications can be discontinued. Stable, long-lasting complete remissions are the goal of thymectomy and may occur in about 50 percent of individuals who undergo this procedure. In a few cases, the severe weakness of myasthenia gravis may cause respiratory failure, which requires immediate emergency medical care.
How is Myasthenia Gravis Treated?
Thymectomy, the surgical removal of the thymus gland (which often is abnormal in individuals with myasthenia gravis), reduces symptoms in some individuals without thymoma and may cure some people, possibly by re-balancing the immune system. Thymectomy is recommended for individuals with thymoma. Other therapies used to treat myasthenia gravis include plasmapheresis, a procedure in which serum containing the abnormal antibodies is removed from the blood while cells are replaced, and high-dose intravenous immune globulin, which temporarily modifies the immune system by infusing antibodies from donated blood. These therapies may be used to help individuals during especially difficult periods of weakness. A neurologist will determine which treatment option is best for each individual depending on the severity of the weakness, which muscles are affected, and the individual’s age and other associated medical problems.
- Mediastinoscopy: A procedure used to examine the mediastinum. The space behind the breastbone (sternum) in the middle of the chest, between the two lungs.
- Anterior mediastinotomy (Chamberlain procedure): A minimally invasive operation used to biopsy lymph nodes or a mass in the center of the chest.
- EBUS (EndoBronchial UltraSound): A procedure used to diagnose infections, lung cancer, and other diseases in the chest.
Within the Federal government, the National Institute of Neurological Disorders and Stroke (NINDS), one of the National Institutes of Health (NIH), has primary responsibility for conducting and supporting research on brain and nervous system disorders, including myasthenia gravis.
Much has been learned about myasthenia gravis in recent years. Technological advances have led to more timely and accurate diagnosis, and new and enhanced therapies have improved management of the disorder. There is a greater understanding about the structure and function of the neuromuscular junction, the fundamental aspects of the thymus gland and of autoimmunity, and the disorder itself. Despite these advances, however, there is still much to learn. Researchers are seeking to learn what causes the autoimmune response in myasthenia gravis, and to better define the relationship between the thymus gland and myasthenia gravis.
Different drugs are being tested, either alone or in combination with existing drug therapies, to see if they are effective in treating myasthenia gravis. One study is examining the use of methotrexate therapy in individuals who develop symptoms and signs of the disease while on prednisone therapy. The drug suppresses blood cell activity that causes inflammation. Another study is investigating the use of rituximab, a monoclonal antibody against B cells which make antibodies, to see if it decreases certain antibodies that cause the immune system to attack the nervous system. Investigators are also determining if eculizumab is safe and effective in treating individuals with generalized myasthenia gravis who also receive various immunosuppressant drugs.
Another study seeks further understanding of the molecular basis of synaptic transmission in the nervous system. The objective of this study is to expand current knowledge of the function of receptors and to apply this knowledge to the treatment of myasthenia gravis.
Thymectomy is also being studied in myasthenia gravis patients who do not have thymoma to assess long-term benefit the surgical procedure may have over medical therapy alone.
One study involves blood sampling to see if the immune system is making antibodies against components of the nerves and muscle. Researchers also hope to learn if these antibodies contribute to the development or worsening of myasthenia gravis and other illnesses of the nervous system.
Investigators are also examining the safety and efficacy of autologous hematopoietic stem cell transplantation to treat refractory and severe myasthenia gravis. Participants in this study will receive several days of treatment using the immumosuppressant drugs cyclophosphamide and antithymocyte globulin before having some of their peripheral blood cells harvested and frozen. The blood cells will later be thawed and infused intravenously into the respective individuals, whose symptoms will be monitored for five years.
For more information on neurological disorders or research programs funded by the National Institute of Neurological Disorders and Stroke, contact the Institute’s Brain Resources and Information Network (BRAIN) at:
P.O. Box 5801
Bethesda, MD 20824