Most scientists and doctors in the field believe that Multiple Sclerosis is an autoimmune disease. It is the destruction of the protective covering of the nerves of the central nervous system and brain. The immune cells for some unknown reason, turn against the myelin sheath of these nerves. The destroyed portions are replaced with scar tissue. It can happen at any number of portions of any central nerve. Hence the name Multiple Sclerosis or MS. Like other autoimmune diseases, MS also has the character of periodic flare-ups and remissions. Many of the features of multiple sclerosis are peculiar. Women are more prone to it than men. The month of birth appears to be a factor in its development. Its incidence is higher as one moves away from the equator. Diagnosis and treatments are still a challenge.
Nerves have a central core of nerve fiber which is covered by a very thick layer of Myelin. This layer, in addition to protecting the central nerve fiber bundle, plays an important role in the conduction of the electrical nerve impulses. When this sheath is damaged and replaced with scar tissue, the transmission of the nerve impulses is impaired. If the myelin is totally absent the conduction of the outward signal stop altogether. Since the attack can take place on anywhere on any nerve the symptoms of the disease is varied. The locations where the myelin is either partially or completely damaged and replaced with scar tissue is called plaques or lesions. As the lesions grow more the nerve suffers damage and can even break. It is the outward conduction that suffers.
The exact causes for this are not known. What are known are the risk factors and some of the trigger factors. Treatment centers around suppression of the immune system with all its attendant complications.
Some of the commonly established factors that usually most likely to be the target of MS are the age group of 18 to 60 years, women, those of European descent, genetics and heredity, the geographical location. Higher away from the equator the incidence of MS increases. There appears to have multiple triggers, rather than a single or limited. Similarly, the known trigger are infections, especially viruses like Epstein-Barr (mononucleosis), varicella zoster. This is not completely established.
Urge incontinence or urine retention, constipation, memory loss, difficulty in finding words, depression and emotional changes are some of the common complaints. Life expectancy is generally not affected.