What is Multiple Sclerosis?
Multiple Sclerosis (MS) is a disease of the nervous system, mainly the brain and spinal cord. The nervous system acts as a communications center, sending and receiving messages to and from the brain. These messages are conveyed as impulses traveling along nerve fibers from the brain through the spinal cord and through the nerves branching off it. Most of these nerve fibers are covered along their length with a substance called myelin. MS attacks the myelin, causing scarring (sclerosis).
Causes of Multiple Sclerosis
The cause is unknown, but many researchers think that the immune system is in some way involved. There may also be an inherited tendency that increases susceptibility to Multiple Sclerosis. One common theory holds that an unidentified virus, acquired in youth, triggers the immune system to turn against itself. As part of this response, the immune system attacks the body’s own myelin, resulting in MS. The disease is unevenly distributed over the globe, with a much lower incidence in tropical areas. The critical geographical factor seems to be the area in which people spend the first 15 years of their lives. After this age, their probability of developing the disease corresponds to its incidence in the area they spent their childhood and early adolescence.
Symptoms of MS
Symptoms vary widely, may occur in any order and may disappear for long periods. Among the more common symptoms are:
- Loss of vision in one eye and double vision
- Psychological changes, such as mood swings, apathy and lack of judgment
- Staggering or loss of balance
- Dragging one or both feet
- Hand tremors
- Facial numbness or pain
- Loss of bladder control leading to increased urinary tract infections
- Speech problems
- Loss of hearing
- Pins and needles sensations in various parts of the body, prickling or numbness
- Increasing disability or paralysis on one side
- Impotence in men
How is MS diagnosed?
MS is difficult to diagnose because the symptoms are so variable and so intermittent. A physical examination may reveal nothing in early stages, and the person’s complaints may be dismissed as imaginary or emotional. Often, diagnosis is by a series of tests to eliminate other possible causes. MS may be confirmed by evoked response testing. This involves recording the speed of electrical response in the brain to an external stimulus, such as a flashing light. The speed of electrical response is usually slowed down in MS because of damage to the myelin sheaths. There is no cure for MS, but attacks can sometimes be reduced in intensity. Treatment is aimed at relieving symptoms.
The course of MS
While the course of MS is highly varied and unpredictable, in most patients it comes and goes. The disease usually begins between the ages of 20 and 40. The periods when symptoms disappear are called remissions. At first, months or years of remission may occur between episodes of the disease, but usually the intervals become gradually shorter. Disability is normally progressive and permanent, but the person’s life span is rarely shortened. Some people have frequent attacks and rapidly become incapacitated, while others are able to lead normal lives and continue with their normal job even though they may be bothered by symptoms at times.