Multiple sclerosis

Definition

Multiple sclerosis is an autoimmune disease that affects the brain and spinal cord (central nervous system).

Alternative Names

MS; Demyelinating disease

Causes

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 signals slow down or stop.

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

It is unknown what exactly causes this to happen. The most common thought is that a virus or gene defect, or both, are to blame. Environmental factors may play a role.

You are slightly more likely to get this condition if you have a family history of MS or live in an part of the world where MS is more common.

Symptoms

Symptoms vary, because the location and severity of each attack can be different. Attacks can last for days, weeks, or months. Attacks are followed by 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.

Nerves in any part of the brain or spinal cord may be damaged. Because of this, MS symptoms can appear 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 symptom as MS progresses. It is often worse in the late afternoon.

Exams and Tests

Symptoms of MS may be mimic those of many other nervous system problems. MS 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 doctor 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.

An exam of the nervous system may show reduced nerve function in one area of the body. Or it may be spread over many parts of the body. This may include:

An eye examination may show:

Tests to diagnose multiple sclerosis include:

Treatment

There is no known cure for multiple sclerosis at this time. But, there are treatments that may slow the disease. The goal of treatment is to control symptoms and help you maintain a normal quality of life.

Medicines are often taken long-term. These include:

The following may also be helpful for people with MS:

Support Groups

Living with MS may be a challenge. You can ease the stress of illness by joining an MS support group. Sharing with others who have common experiences and problems can help you not feel alone.

Outlook (Prognosis)

Outcome varies, and is hard to predict. Although the disorder is chronic and incurable, life expectancy can be normal or almost normal. Most people with MS are active and function at work with little disability.

The following typically have the best outlook:

The amount of disability and discomfort depends on:

Most people return to normal or near-normal function between attacks. Slowly, there is greater loss of function with less improvement between attacks.

Possible Complications

When to Contact a Medical Professional

Call your health care provider if:

References

Houtchens MK, Lublin FD, Miller AE, Khoury SJ. Multiple sclerosis and other inflammatory demyelinating diseases of the central nervous system. In: Daroff RB, Fenichel GM, Jankovic J, Mazziotta JC, eds. Bradley’s Neurology in Clinical Practice. 6th ed. Philadelphia, Pa: Elsevier Saunders; 2012:chap 54.

Polman CH, Reingold SC, Banwell B, et al. Diagnostic criteria for multiple sclerosis: 2010 revisions to the McDonald criteria. Ann Neurol. 2011;69:292–302.

Rubin S. Management of multiple sclerosis: an overview. Disease-a-Month. 2013;59:253–260.