What is multiple sclerosis?

Answer 1

a chronic degenerative, often episodic disease of the central nervous system marked by patchy destruction of the myelin that surrounds and insulates nerve fibers, usually appearing in young adulthood and manifested by one or more mild to severe neural and muscular impairments, as spastic weakness in one or more limbs, local sensory losses, bladder dysfunction, or visual disturbances.

Answer 2

In shor i've had it since 2001 and it sucks.
now the long answer:
"Multiple sclerosis (abbreviated MS, also known as disseminated sclerosis) is a chronic, inflammatory disease that affects the central nervous system (CNS). MS can cause a variety of symptoms, including changes in sensation, visual problems, muscle weakness, depression, difficulties with coordination and speech, severe fatigue, and pain. Although many patients lead full and rewarding lives, MS can cause impaired mobility and disability in the more severe cases.

Multiple sclerosis affects neurons, the cells of the brain and spinal cord that carry information, create thought and perception, and allow the brain to control the body. Surrounding and protecting some of these neurons is a fatty layer known as the myelin sheath, which helps neurons carry electrical signals. MS causes gradual destruction of myelin (demyelination) and transection of neuron axons in patches throughout the brain and spinal cord. The name multiple sclerosis refers to the multiple scars (or scleroses) on the myelin sheaths. This scarring causes symptoms which vary widely depending upon which signals are interrupted. It is thought that MS results from attacks by an individual's immune system on the nervous system and is therefore categorized as an autoimmune disease.

Multiple sclerosis may take several different forms, with new symptoms occurring either in discrete attacks or slowly accruing over time. Between attacks, symptoms may resolve completely, but permanent neurologic problems often persist. Although much is known about how MS causes damage, its exact cause remains unknown. MS currently does not have a cure, though several treatments are available which may slow the appearance of new symptoms. MS primarily affects adults, with an age of onset typically between 20 and 40 years, and is more common in women than in men."

Answer 3

My definition:
MS (Multiple Sclerosis) is an autoimmune disease where the immune system somehow crosses the blood-brain barrier and starts to attack the myelin sheath (protective nerve coating). During a flare up, it is beleived, that the immune system is actively attacking at that time. Various neurological symptoms can occur.

National MS Society Definition:

What Is Multiple Sclerosis?

MS is thought to be an autoimmune disease that affects the central nervous system (CNS). The CNS consists of the brain, spinal cord, and the optic nerves. Surrounding and protecting the nerve fibers of the CNS is a fatty tissue called myelin, which helps nerve fibers conduct electrical impulses.


In MS, myelin is lost in multiple areas, leaving scar tissue called sclerosis. These damaged areas are also known as plaques or lesions. Sometimes the nerve fiber itself is damaged or broken.


Myelin not only protects nerve fibers, but makes their job possible. When myelin or the nerve fiber is destroyed or damaged, the ability of the nerves to conduct electrical impulses to and from the brain is disrupted, and this produces the various symptoms of MS.


People with MS can expect one of four clinical courses of disease, each of which might be mild, moderate, or severe.
Relapsing-Remitting
Characteristics: People with this type of MS experience clearly defined flare-ups (also called relapses, attacks, or exacerbations). These are episodes of acute worsening of neurologic function. They are followed by partial or complete recovery periods (remissions) free of disease progression.
Frequency: Most common form of MS at time of initial diagnosis. Approximately 85%.

Primary-Progressive
Characteristics: People with this type of MS experience a slow but nearly continuous worsening of their disease from the onset, with no distinct relapses or remissions. However, there are variations in rates of progression over time, occasional plateaus, and temporary minor improvements.
Frequency: Relatively rare. Approximately 10%.

Secondary-Progressive
Characteristics: People with this type of MS experience an initial period of relapsing-remitting MS, followed by a steadily worsening disease course with or without occasional flare-ups, minor recoveries (remissions), or plateaus.
Frequency: 50% of people with relapsing-remitting MS developed this form of the disease within 10 years of their initial diagnosis, before introduction of the "disease-modifying" drugs. Long-term data are not yet available to demonstrate if this is significantly delayed by treatment.

Progressive-Relapsing
Characteristics: People with this type of MS experience a steadily worsening disease from the onset but also have clear acute relapses (attacks or exacerbations), with or without recovery. In contrast to relapsing-remitting MS, the periods between relapses are characterized by continuing disease progression.
Frequency: Relatively rare. Approximately 5%.