|
|
You are here: Home  Learn about MS Quick Links What is Multiple Sclerosis?
|
|
What is Multiple Sclerosis? |
Multiple sclerosis is one of a category of diseases called autoimmune diseases. In an autoimmune disease, the individual’s immune system mistakenly targets and destroys parts of the person’s body.
The targeted areas in MS are in the brain and spinal cord. Specific immune system cells called lymphocytes appear to zero in on the nerve fibers (axons) and their insulating cover (myelin). When the myelin and axons are attacked, small, oval scars form in the white matter of the brain and spinal cord. These scars are also known as sclerosis or plaques. Those scars cause messages from the central nervous system to be short-circuited on their way out to the body, thus creating neurologic symptoms. Each person with MS has a unique pattern of plaque formation and thus may experience a variety of symptoms. The symptoms of MS can include:
- pain, numbness, or tingling
- fatigue
- decreased or double vision
- problems with coordination and balance
- bladder and/or bowel problems
- muscle stiffness (spasticity)
- dizziness and vertigo
- weakness
- difficulty walking
- problems with thinking, memory, and attention
- sexual dysfunction
As the name "multiple sclerosis" implies, multiple areas of damage (scars or sclerosis) may be present in the brain and spinal cord. The name also reflects the episodic, ongoing nature of the disease. In fact, in order to make a confirmed diagnosis of multiple sclerosis, a physician must be able to document at least two neurologic areas affected in the person’s body and at least two episodes where a person experiences symptoms.
MS symptoms may occur rather suddenly. After an attack, or exacerbation, more than 75 percent of MS patients will improve without treatment (a remission). Even those who are considered to be in remission often experience some symptoms with their MS, such as fatigue, spasticity, numbness, or tingling. However, some MS patients do not have attacks and remissions, but instead have a continuous progression of symptoms that do not recede. About two-thirds of MS patients live normal lives, sometimes aided with the help of adaptive equipment. The remaining one-third become physically disabled and may require wheelchairs.
While MS is different for every person, five types are most often identified.
Relapsing-remitting MS means the person has attacks and recovers some or most of their function.
Secondary-progressive MS occurs when some people with relapsing-remitting disease start to progress between attacks or after they stop having attacks
Primary-progressive MS begins as a progressive disease without attacks and is usually diagnosed between the ages of 40 and 60.
Progressive-relapsing shows progression from the beginning, but with attacks occurring on occasion.
Benign MS is characterized by attacks followed by complete or nearly complete recovery, resulting in little or no functional losses after several years.
Multiple sclerosis is not usually a fatal disease. The life expectancy of a person with MS is close to that of the general population. A person with MS can experience significant functional losses, however, and become increasingly disabled as the disease progresses.
The cause of multiple sclerosis remains a mystery. Multiple sclerosis is like a giant puzzle with scientists searching for the many pieces. It is only a matter of time until enough pieces of the puzzle will be found to identify the cause.
Some clues to the cause of multiple sclerosis include:
- Age. Studies of people who have lived in high risk areas for MS between the ages of 10 and 15 suggest that exposure to some factors (possibly viruses) in the environment during adolescence makes one more susceptible to MS many years later.
- Genetics. Although most people diagnosed with MS do not have a family history of the disease, we know that some families do have several affected members, sometimes spanning several generations. MS is much more commonly diagnosed among people of Northern European descent that people of other races, even when other racial groups traditionally live in temperate climates. The heightened incidence of MS in some families may be related to a genetic predisposition, however, MS is not strictly a hereditary disease caused by one genetic defect. Many genes, each exerting a very small impact, are likely to play a role. Research to identify the genetic roots of MS is underway. Genetic research may also identify why there is such variability in disease progression and whether an individual’s genetic identity may influence the types of disease modifying therapies that are most likely to be helpful.
- Immunology. The immune system is composed of white blood cells, which normally protect the body from viruses, bacteria, cancers, and other "foreign agents." However, this system may react abnormally in MS patients, and, in fact, may play a major role in the cause of multiple sclerosis. Lymphocytes are triggered or activated, then travel through the blood-brain barrier to enter the brain and set off a series of chemical and cellular events, which lead to myelin and axon damage. A heavy focus of current research aims to identify the initiating activities in this presumed cascade of events.
- Virus. One or more viruses may play a role in the cause of multiple sclerosis. Viruses may be the predisposing "environmental factor" in MS. It is very important to emphasize that MS is not contagious. People with MS should be conscious about their health as viral infections such as "colds" may increase the risk of an exacerbation (attack).
One theory postulates that exposure to a virus predisposes the body's immune system to malfunction and attack myelin. In this theory, many factors must act together. They include an environmental factor (virus?) attacking a susceptible person (possibly genetically determined), at a specific age (possibly between the ages of 10 and 15). Other factors may also be necessary to set the stage for multiple sclerosis.
It is estimated that there are approximately 350,000 persons in the United States with MS. Multiple sclerosis is the most common neurologic disease diagnosed in young adults (ages 20 to 50). For every person in Denver with muscular dystrophy or amyotrophic lateral sclerosis (Lou Gehrig's Disease), there are more than ten people with multiple sclerosis. MS is more common among Caucasians than in other racial populations. Approximately two-thirds 2/3 of those diagnosed with MS are women.
|
|
|
Contact
