What is Multiple Sclerosis?
Multiple Sclerosis is a neurological disease which infects approximately 80.000 people in Britain and 250.000 in the USA. The signs and symptoms have been identified for a century and a half and since then extensive research has been underway, despite this however, the cause of Multiple Sclerosis remains unknown.
Multiple Sclerosis is a chronic disease of the central nervous system. The Central Nervous System is made up of the brain and spinal cord. It usually appears between the ages of 25 and 40. It rarely appears at the age of 12 or after 50.
Multiple Sclerosis appears in countries with a Mediterranean climate and rarely in tropical countries. Symptoms are caused by the demyelination or in other words the “scars” that form in the central nervous system. The reasons for demyelination still remain unknown.
The Central Nervous System
Our brain processes and interprets stimuli that it receives from our senses, it gives orders and is responsible for such functions as motor control, relaying sensory information and controlling autonomic functions. This activity of the brain consists of a series of complex networks of neurons which begin from the brain and via the spinal cord spread to all parts of the body.
Each nerve can be compared to an electricity cable. Within a nerve, each axon is surrounded by a layer of connective tissue called the endoneurium which allows for communication and transmits information or stimulation throughout the whole body, just like the wires of an electric cable. The axon of each nerve is coated by a layer of thick substance known as Myelin, just like the plastic coating of an electric cable. Myelin helps with the transmission of information from nerve to nerve but it also isolates and protects the nerve.
In Multiple Sclerosis the immune system infects a part of the Myelin sheath or the cells that produce and maintain it. This causes inflammation and injury to the sheath and ultimately to the nerve fibres that it surrounds, and may result in multiple areas of scarring (sclerosis). When the inflammation subsides, it may not leave any scars. If, however, the process of demyelination continues, then the myelin in that area is destroyed, leaving scars named plaques or lesions (multiple sclerosis).
This process is called demyelination. These scars appear at different times and in different areas of the brain and/or spinal cord and that is why this disease is called Multiple Sclerosis. The term Multiple Sclerosis means, literally, many scars.
Symptoms of Multiple Sclerosis
Multiple Sclerosis is a disease with many changes. Demyelination can infect the motor as well as sensory nerves, thus affecting movement, touch and other senses.Symptoms vary widely depending on which nerves have been infected.
There is not just one type of Multiple Sclerosis. Each patient presents symptoms which another patient may not have. It is also possible that the symptoms of that patient may vary from time to time. Some of the symptoms are visible however others such as tiredness, changes in sensation, memory loss and concentration problems are usually “hidden” symptoms and are difficult to describe to others.
There is no “standard” form of Multiple Sclerosis. It is a “personalised” disease and therefore impossible to describe the disease generally or give a certain prognosis.
There are however certain symptoms which are common amongst most patients:
a) double vision
b) weakness or inability to use limbs
c) changes in sensation of hands and feet, e.g. tingling, pins and needles or numbness.
d) dizziness or instability
e) tiredness/fatigue which is disproportionate to our activities or unexpected fatigue
f) need for frequent or hasty urination