A chronic, disabling disease of the central nervous system where the body causes injury to the sheath that covers the nerves of the central nervous system, causing them to degenerate.
There are several main types of multiple sclerosis:
- Relapsing-remitting multiple sclerosis — A condition where symptoms suddenly reappear every few years and last for only a few weeks or months before going back into remission.
- Primary progressive multiple sclerosis — A condition where there is no relapse or remission period and symptoms gradually worsen after first appearing.
- Secondary progressive multiples sclerosis — A condition where there are multiple relapses and remissions, and each time symptoms progressively worsen.
- Progressive relapsing multiple sclerosis — A condition where one or more relapse may occur, characterized by symptoms that gradually worsen after the first appearance.
The direct cause of multiple sclerosis is unknown. However, researchers speculate that a foreign agent (such as a virus) may alter the immune system enough so that it perceives the sheath that covers the nerves as an intruder and attacks it.
With multiple sclerosis, the nerves of the brain and spinal cord are damaged. As a result, functions that are controlled by the nervous system such as vision, speech, writing, and memory can be affected depending on the severity of the damage. Other symptoms can include dizziness, limb weakness, depression and muscle spasms.
Treatment procedures most typically involve using certain drugs and medications to either slow the progression of the disease or improve the speed of recovery. If a person experiences a loss of function of a specific organ, certain medications can also be given directly aimed to lessen the symptoms.