Multiple sclerosis

A progressive disease of the central nervous system in which patches of myelin in the brain and spinal cord are destroyed. Multiple sclerosis (or MS) is an autoimmune disorder, in which the immune system attacks the myelin sheath that covers some nerves in the brain and spinal cord. Affected nerves cannot conduct nerve impulses, so functions such as movement and sensation may be lost. Any area of the body can be affected. Symptoms range from numbness and tingling to paralysis and incontinence. Attacks of symptoms are followed by a variable period of remission, in which dramatic improvements may be made. Women are more likely to develop MS than men, and there may be a genetic factor, as the disease sometimes runs in families. There may also be an environmental factor, as MS is more common in temperate zones than in the tropics. Symptoms usually develop early in adulthood. Spinal cord damage may cause tingling, numbness, weakness in the extremities, spasticity, paralysis, and incontinence. Damage to white matter (myelinated nerves) in the brain may cause fatigue, vertigo, clumsiness, muscle weakness, slurred speech, blurred vision, numbness, weakness, or facial pain. Attacks may last several months. After a variable remission period, a relapse occurs, which may be precipitated by injury, infection, or stress. Some people have mild relapses and long periods of remission, with few permanent effects. Some people become gradually more disabled from the first attack. A few suffer gross disability within the 1st year. There is no single diagnostic test, but MRI may show damage to white matter in the brain. Evoked response tests on the eyes also provide strong evidence. There is no specific treatment. Some people claim that dietary modifications such as sunflower or evening primrose oils are beneficial. In some cases, interferon beta can extend the time between attacks and reduce the rate of decline.


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