Learn what multiple sclerosis is and the factors that influence this disease.

What is multiple sclerosis?

Multiple sclerosis (MS) is an inflammatory demyelinating disease that affects the central nervous system (CNS). It is called “sclerosis” because as a result of the disease, the nervous tissue hardens (similar to a scar) in certain areas of the brain and spinal cord. It is called “multiple” because various areas of the brain and spinal cord can be affected.

Although the exact cause of MS is unknown, many scientists believe that the destruction of myelin is the result of an abnormal immune response to the body itself. The immune system defends the body against foreign invaders, such as viruses or bacteria, and has the ability to differentiate between self and non-self structures. The body’s integrity is maintained through the mechanism of tolerance, which prevents recognition of self. The disruption of this balance is highly relevant in the development of autoimmune diseases. In these diseases, the body attacks its own tissue without warning.

In MS, the substance attacked is not any “invader,” but rather myelin, a material composed of proteins and fat that coats, protects, and wraps around nerve fibers of the central nervous system, facilitating the conduction of electrical impulses between nerve fibers. If this myelin is destroyed or damaged, the ability of nerves to conduct electrical impulses from the brain is interrupted, leading to the appearance of symptoms (spasticity, slowing of movement commands, aphasia, etc.).

The cause of the disease is not yet known, but the most accepted theory is that MS is the result of several factors:


Certain information present in genes that may determine a predisposition to the disease.


Viruses, vaccines, etc., that can trigger the disease in predisposed individuals.