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What is MS
Causes
Symptoms
Treatment
Outlook
References

What Causes MS?

Multiple sclerosis (MS) affects women more than men. The disorder is most commonly diagnosed between ages 20 and 40, but can be seen at any age.

MS is caused by damage to the myelin sheath, the protective covering that surrounds nerve cells. When this nerve covering is damaged, nerve impulses are slowed down or stopped.

The nerve damage is caused by inflammation. Inflammation occurs when the body's own immune cells attack the nervous system. Repeated episodes of inflammation can occur along any area of the brain, optic nerve, and spinal cord.

Researchers are not sure what triggers the inflammation. The most common theories point to a virus or genetic defect, or a combination of both. Geographic studies indicate there may be an environmental factor involved.
People with a family history of MS and those who live in a geographical area where MS is more common have a slightly higher risk of the disease.

The major scientific theories about the causes of MS include the following:

Immunologic

It is now generally accepted that MS involves an autoimmune process—an abnormal response of the body’s immune system that is directed against the myelin (the fatty sheath that surrounds and insulates the nerve fibers) in the central nervous system

Environmental

MS is known to occur more frequently in areas that are farther from the equator. Epidemiologists—scientists who study disease patterns—are looking at many factors, including variations in geography, demographics (age, gender, and ethnic background), genetics, infectious causes, and migration patterns, in an effort to understand why.

Infectious

Since initial exposure to numerous viruses, bacteria and other microbes occurs during childhood, and since viruses are well recognized as causes of demyelination and inflammation, it is possible that a virus or other infectious agent is the triggering factor in MS.

Genetic

While MS is not hereditary in a strict sense, having a first-degree relative such as a parent or sibling with MS increases an individual's risk of developing the disease several-fold above the risk for the general population. Studies have shown that there is a higher prevalence of certain genes in populations with higher rates of MS.

Symptoms

Symptoms vary, because the location and severity of each attack can be different. Episodes can last for days, weeks, or months. These episodes alternate with periods of reduced or no symptoms (remissions).
Fever, hot baths, sun exposure, and stress can trigger or worsen attacks.

It is common for the disease to return (relapse). However, the disease may continue to get worse without periods of remission.

Because nerves in any part of the brain or spinal cord may be damaged, patients with multiple sclerosis can have symptoms in many parts of the body.

Muscle symptoms:

Bowel and bladder symptoms:

Eye symptoms:

Numbness, tingling, or pain

Other brain and nerve symptoms:

Sexual symptoms:

Speech and swallowing symptoms:

Fatigue is a common and bothersome symptoms as MS progresses. It is often worse in the late afternoon.

Exams and Tests

Symptoms of MS may mimic those of many other nervous system disorders. The disease is diagnosed by ruling out other conditions.

People who have a form of MS called relapsing-remitting may have a history of at least two attacks, separated by a period of reduced or no symptoms.

The health care provider may suspect MS if there are decreases in the function of two different parts of the central nervous system (such as abnormal reflexes) at two different times.

A neurological exam may show reduced nerve function in one area of the body, or spread over many parts of the body.

This may include:

An eye examination may show:

Tests to diagnose multiple sclerosis include: