What Is Multiple Sclerosis?

You probably know your nerves carry messages around your body. So if you stub your toe, your nerves deliver the message to your brain that says "Ouch!" Nerves also send signals that tell your muscles what to do when you want to walk and run.

In someone who has multiple sclerosis (MS), there are roadblocks in the pathways so the messages don't get to the brain like they should.

That leads to problems like:

• vision problems
• fatigue or weakness
• difficulty walking or trouble with balance or coordination
• numbness or the pins-and-needles tingling you feel when your foot falls asleep
• memory problems

Over 2 million people around the world have MS, including about 400,000 Americans. MS is mostly a disease that adults get and is usually diagnosed between the ages of 20 and 50. It is more common in women than men.

If you know someone who has MS, you probably want to know what the disease will be like. The disease does tend to get slowly worse over time, but most people with MS have mild symptoms and live to be as old as people without MS.

Let's talk about what's causing those roadblocks for the signals. If a person has MS, the immune system — which usually fights germs — attack nerves in the brain and spinal cord. It damages the layer of tissue, called myelin, which surrounds and protects the nerves.

When myelin becomes damaged, scars develop. Sclerosis comes from the Greek word for scarring or hardening. And those scars can act like stones in the road, creating a bumpy ride for signals as they travel between the brain and body.

When those signals get slowed down or blocked, people with MS feel one or more symptoms, such as vision problems or feeling unsteady on their feet. The symptoms will vary depending on what nerves are affected.

Different Types of Multiple Sclerosis

There are four different categories of MS:

1. Relapsing-Remitting: This is the most common form of MS, and symptoms come and go. People with this type will have flare-ups (relapses) of symptoms. The problems will lessen (remit) or completely vanish, and there is a period of time between relapses when the person has no symptoms (remission).
2. Primary-Progressive: People with this kind of MS have constant symptoms, which tend to get worse over time.
3. Secondary-Progressive: People with secondary-progressive start out with a period of relapsing-remitting symptoms before symptoms gradually get worse. Without treatment, about half of people in the relapsing-remitting category will develop this form of MS within 10 years.
4. Progressive-Relapsing: People in this category get steadily worse but also have occasional flare-ups, or relapses. This is the rarest form of MS.

Can Kids Get MS?

MS is rare in kids. About 5% of cases of MS are diagnosed in children. MS in kids tends to progress more slowly than MS diagnosed in adults.

Multiple sclerosis is not contagious, so you can't catch it from someone who has it. And it's not hereditary. That means the disease is not passed on directly from one generation to the next, like eye color.

But your chances of developing MS are greater if a close relative, such as a parent or sibling, has it. Scientists are still studying why.

How Is Multiple Sclerosis Diagnosed?

When people begin to experience what could be early signs of MS, such as vision or balance problems, doctors will take a careful history and do a complete physical exam. Since there is no one test that can determine if a person has MS, the doctor may order several tests, including blood tests, cerebrospinal fluid (the fluid that surrounds the brain and spinal cord) tests, and brain scans.

A brain MRI, or magnetic resonance imaging test, lets a doctor check for evidence of scars in the brain and spinal cord by taking detailed pictures of these body areas.

Another frequent stop on the way to an MS diagnosis is a series of evoked potentials (EP) tests, which test the time it takes for nerves to respond. If the response time is slow, the chances are greater that there's damage along the nerve pathways.

How Is MS Treated?

Currently, there is no known cure for multiple sclerosis, but medications can help control symptoms. When a flare-up or relapse happens, steroids lessen inflammation and quicken recovery. Several medicines can be given to reduce the number of relapses and slow down progression of the disease.

People with MS can take steps to manage symptoms, including physical and occupational therapy. Eating a balanced diet and exercising regularly are also important when it comes to overall health and well-being for people living with MS.

Helping Someone With MS

If someone you love has MS, you can be supportive in lots of ways. The person might appreciate some help with stuff like opening doors. If you live with this person, it's great to be quiet when he or she is resting.

As you get older, you might be able to help with other stuff, like getting groceries or doing other stuff around the house. But most of all, the person will like knowing that you're understanding and ready to help.

Reviewed by: Mary L. Gavin, MD
Date reviewed: July 2011