Autoimmune disorders are conditions that occur when the immune system--the body’s defense system--attacks the body's own tissues as if they were foreign. That leads to destruction of healthy tissue, changes in organ function or abnormal growth of an organ.
Autoimmune disorders of the nervous system can attack the central nervous system (CNS), which includes the brain and spinal cord, or the peripheral nervous system, consisting of nerves that connect the CNS with the limbs and organs. The most common disorders are multiple sclerosis and myasthenia gravis.
Multiple sclerosis (MS) is a chronic inflammatory autoimmune disorder of the CNS. In MS, the myelin sheaths that coat nerves and assist in nerve impulse transmission are destroyed. This process is called demyelination, and it results in damaged nerves that cannot transmit impulses.
Demyelination can happen in parts of the CNS that control different body functions, leading to symptoms in various organs. They include muscle symptoms (balance-loss, numbness, difficulty walking, weakness), bowel and bladder symptoms, eye symptoms (double vision, vision loss) and other symptoms, including pain, depression, memory loss and poor judgment.
Myasthenia gravis is a chronic autoimmune disorder that attacks skeletal (voluntary) muscles and the nerves that control them, resulting in muscle weakness that worsens with activity and improves with rest. This is due to a defect in transmission of the nerve impulses between the nerves and muscles.
Symptoms include difficulty breathing, swallowing, talking, climbing stairs or lifting objects; facial paralysis; and fatigue.
Less Common Disorders
In Guillain-Barré syndrome, myelin sheaths of the peripheral nervous system are destroyed. Such nerves cannot transmit signals to the muscles, leading to muscle weakness--sometimes even paralysis.
Rare chronic inflammatory demyelinating polyneuropathy (CIDP) is caused by swelling of nerve roots and destruction of myelin sheaths, leading to weakness, paralysis, and/or impairment in motor function.
Transverse myelitis (TM) is an uncommon syndrome caused by inflammation of the spinal cord, causing weakness, back pain, and bowel and bladder problems.
According to the American Autoimmune Related Diseases Association (AARD), autoimmune diseases remain among the most poorly understood of any category of illnesses. Predisposition to the autoimmune disorders may be inherited, but genes alone do not cause the disorders. Environmental factors may be disease triggers, such as bacteria, viruses, toxins and some drugs. In MS, myelin damage is due to inflammation, but what triggers the inflammation remains unknown.
Treatment and Help
Autoimmune diseases of the nervous system are often chronic, requiring lifelong care and monitoring. Corticosteroids and intravenous immunoglobulin therapy are used to try and slow the immune disorders.
There is no known cure for MS, but drugs can slow the progression of the disease, decrease the severity of attacks, and/or control the symptoms and help patients maintain a normal quality of life. Physical and speech therapy, exercise and healthy lifestyles can help reduce the symptoms of MS.
Myasthenia gravis has no known cure, but treatment may result in prolonged periods without any symptoms, including medications that improve the communication between nerves and muscles. Planning activity with rest periods usually is necessary for sufferers to function.
Support groups are available for many of these disorders to inform patients and help them cope with their diseases.