multiple sclerosis

Multiple Sclerosis (MS)

What is Multiple Sclerosis?

Multiple sclerosis is currently thought to be an autoimmune disease.
An autoimmune disease is one where the body's immune system is thought to attack its own cells and therefore cause damage.

In multiple sclerosis, the area which is predominantly affected is the Central Nervous System (CNS), and in particular the myelin.

What is definitely known about multiple sclerosis is that there is considerable destruction of the myelin. This is one of the characteristics of the disease.

Myelin is the white, fatty substance surrounding and protecting the nerve fibers of the brain and the spinal cord and helping it to function properly.

When the myelin becomes damaged, there is an interruption to the normal flow of nerve signals and impulses. This typically causes symptoms in those areas which are innervated (supplied by the nerve).

For example, if the damage occurs to an area of the brain or spinal cord related to movement, this may cause incoordination or loss of movement. Should the damage occur to an area of the central nervous system related to sensation, then this may cause numbness or strange feelings on the skin such as tingling.

Although myelin does have the capacity to regenerate, this is usually very slow to occur.

Damage to the myelin causes the body to produce an inflammatory response, in a similar way to that seen when the skin gets scratched.

This results in the formation of scar tissue at the site of damage and in the same way that scarring of the skin can be permanent if the damage is severe enough, scarring which occurs due to damage to the myelin can also be permanent.

When a scar forms due to damage to the myelin, the body is generally unable to completely repair the tissue to its former undamaged state since the regeneration of myelin is comparatively slow and therefore the scarring eventually becomes permanent and leads to malfunctioning of the area of the body corresponding to the interrupted nerve impulses.

For example, if a scar; more often referred to as a lesion or plaque, forms and interrupts the normal flow of nerve impulses from the sensation of touch in the fingers, then this can cause someone to drop things since the flow of feedback nerve-impulses from the fingers is interrupted.

The same process can occur regarding any area of the body and so the range of different symptoms which multiple sclerosis can cause is very varied although there are some symptoms which are more common than others; for example, optic neuritis.

Although multiple sclerosis cannot be cured, there are some treatments available which can help slow the progression towards disability in some patients.