Definition and causes
Multiple sclerosis is also calleddisseminatedsclerosis. It is a chronic neurological disease that affects various parts of the central nervous system, so that they gradually destroyed.
In the early years with multiple sclerosis are often attacks (relapses) with various symptoms, which disappeared completely or partially. Later in the course of these symptoms will no longer disappear entirely, leading to increasing disability (see article Symptoms of multiple sclerosis).
Central nervous system consists ofbrainandspinal cord, And here lies alloy members of all nerve cells (gray matter) and their ramifications (white substance). Each nerve cell has a variable number of ramifications, which it uses to receive nerve signals from other neurons. These are calledDendrite. In addition, each cell one expires, which could send the cell's own signaling further, a so-calledaxon.
Moreover, there are special help-cells (oligodendrocytter), which produces a fat unhappy about axonet as a kind of insulation. This is called amyelinskedeand contributes to nerve signal can be managed very quickly to protect axonet (as insulation on a wire).
When multiple sclerosis attacked these myelinskeder of the immune system, which they destroyed. That makes nerve signals now can no longer be managed as quickly, and ultimately may itself axonet also destroyed, so there certainly is no conduction of nerve signals.
The reason that the immune system is activated against myelin, is not known in detail. It is believed that some of the white blood cells might be activated against a virus or a bacterium, which has a surface that resembles myelinskedens. Later, these cells then make a mistake and believe that myelinskeden is a virus or bacterium and attack it. This leaves the area without myelin on axonerne (demyelinating) and something arvæv. One such area is called aplagueand can be seen on an MRI of the brain (see also Diagnosis of multiple sclerosis).
Since axonerne lies in the white substance, is the most here, you see disease activity. Not all of the white substance attacked at once, which is why the disease can have very different symptoms (see Symptoms of multiple sclerosis).
You get symptoms from the area that is attacked. This means that if the part to be moving right hand, is attacked, you will have difficulty moving his right hand. If the contrast is the area that leads signals about feeling a sense of left foot, then you will be either reduced or disrupted tactile sense on the left foot.
In the beginning, many of the symptoms disappear again as an indication that the injury on myelinskeden was not complete, and possibly. has formed new myelin around. Later in the disease damage will be so severe that the symptoms are permanent and will often cause further damage elsewhere, leading to new symptoms.
Who gets multiple sclerosis?
There are currently about. 7,000 people with multiple sclerosis in Denmark, and almost every day diagnosed a new case. Diseases affect mostly young people aged 20-40 years. twice as many women as men are affected.
There is some hereditary predisposition for the disease because it is seen more frequently in families where there is a family member with multiple sclerosis. However, it is not actually a hereditary disease, since there anything known gene, which is solely responsible for the development of multiple sclerosis. We believe that what we inherit, have an increased susceptibility to the (unknown) factors that lead to disease.
Learn more about multiple sclerosis at:
Symptoms of Multiple Sclerosis
Diagnosis of Multiple Sclerosis
Treatment of Multiple Sclerosis