Multiple sclerosis (MS) involves an immune-mediated process in which an abnormal response of the body’s immune system is directed against the central nervous system (CNS). The CNS is made up of the brain, spinal cord and optic nerves.
Within the CNS, the immune system causes inflammation that damages myelin — the fatty substance that surrounds and insulates the nerve fibers — as well as the nerve fibers themselves, and the specialized cells that make myelin.
- When myelin or nerve fibers are damaged or destroyed in MS, messages within the CNS are altered or stopped completely.
- Damage to areas of the CNS may produce a variety of neurological symptoms that will vary among people with MS in type and severity.
- The damaged areas develop scar tissue which gives the disease its name – multiple areas of scarring or multiple sclerosis.
- The cause of MS is not known, but it is believed to involve genetic susceptibility, abnormalities in the immune system and environmental factors that combine to trigger the disease.
- People with MS typically experience one of four disease courses (types of MS). There are over a dozen treatments to help modify the MS disease process.