Multiple Sclerosis

Multiple Sclerosis (MS) is a disorder of the brain and spinal cord involving decreased nerve function associated with scar formation on the covering of nerve cells. In many cases, MS symptoms include various stages of paralysis.

Multiple sclerosis involves repeated episodes of inflammation that destroy the myelin sheath that covers nerve fibers, leaving multiple areas of scar tissue (sclerosis) along the covering of the nerve cells. This results in slowing or blockage of nerve impulse transmission in that area.

MS often progresses with episodes that last days, weeks, or months alternating with times of reduced or no symptoms (remission). Recurrence (relapse) is common.

The exact cause of MS is unknown. Studies indicate an environmental factor may be involved. There is a higher incidence in northern Europe, northern United States, southern Australia, and New Zealand than in other areas of the world. There may also be a familial tendency toward the disorder.

MS is believed to be a type an abnormal immune response directed against the central nervous system (CNS). The exact antigen -- the target the immune cells are sensitized to attack -- remains unknown. In recent years, researchers have identified which immune cells are mounting the attack, how they are activated to attack, and some of the sites, or receptors, on the attacking cells that appear to be attracted to the myelin to begin the destructive process.

Theories about the cause of MS include the role of a virus-type organism, an abnormality of the genes responsible for control of the immune system, or a combination of both.

MS affects approximately 1 out of 1,000 people. Women are affected more commonly than men. The disorder most commonly begins between 20 to 40 years old but can happen at any age.

MS symptoms include weakness of one or more extremities, paralysis of one or more extremities, tremor of one or more extremities, muscle spasticity (uncontrollable spasm of muscle groups), movement dysfunction, numbness, tingling, pain, loss of vision, loss or coordination and balance, incontience, loss of memory or judgment and fatigue.

Symptoms may vary with each attack. Fever can trigger or worsen attacks, as can hot baths, sun exposure, and stress.

MS varies greatly from person to person and in the severity and the course of the disease. Some people have few attacks and little disability. Others have "relapsing-remitting" MS which means they have a series of attacks (exacerbations) followed by periods of recovery (remissions).

Some have what is called "progressive" disease that can be "primary" or "secondary." People with primary-progressive MS have steady worsening (or progression) from onset with only minor recovery. Secondary-progressive MS begins with a series of relapses and recovery but becomes steadily progressive over time with continued worsening. Most people with MS have the relapsing-remitting or secondary-progressive forms.

There is no known cure for multiple sclerosis. There are promising new therapies that may decrease exacerbations and delay progression of the disease. Treatment is aimed at controlling symptoms and maintaining function to give the maximum quality of life.

Patients with a relapsing-remitting course are now placed on immune modulating therapy that requires injection under the skin or in the muscle once or several times a week. This may be in the form of interferon (such as Avonex or Betaseron) or another drug called glatiramer acetate (Copaxone). They are all similar in their effectiveness and the decision on which to use depends on one’s side-effect profile.

Steroids are often given to decrease the severity of an attack. Other common MS medicines include baclofen, tizanidine or diazepam may be used to reduce muscle spasticity. Cholinergic medications may be helpful to reduce urinary problems. Antidepressant medications may be helpful for mood or behavior symptoms. Amantadine may be given for fatigue.

Physical therapy, speech therapy or occupational therapy may improve the person’s outlook, reduce depression, maximize function, and improve coping skills. A planned exercise program early in the course of MS helps to maintain muscle tone.

Attempts should be made to avoid fatigue, stress, physical deterioration, temperature extremes, and illness to reduce factors that may trigger an MS attack.

The expected outcome is variable and unpredictable. Although the disorder is chronic and incurable, life expectancy can be normal or nearly so, with a life span of 35 or more years after diagnosis occurring commonly. Most people with MS continue to walk and function at work with minimal disability for 20 or more years.

Here is a good slideshow overview on WebMD.

Sources: National Institute of Neurological Disorders and Stroke (NINDS), National Multiple Sclerosis Society, Consortium of MS Centers