brain, spinal cord, and nerve disorders
Other Primary Demyelinating Diseases
Introduction
Disorders that cause Overview of Demyelinating Disorders and have no known cause are called primary demyelinating disorders. Demyelination is the destruction of the tissues that wrap around nerves, called the myelin sheath. Most nerve fibers inside and outside the brain are wrapped with many layers of tissue composed of a fat (lipoprotein) called myelin. These layers form the myelin sheath. Much like the insulation around an electrical wire, the myelin sheath enables nerve signals (electrical impulses) to be conducted along the nerve fiber with speed and accuracy. When the myelin sheath is damaged (called demyelination), nerves do not conduct electrical impulses normally. Sometimes primary demyelinating disorders develop after a viral infection or vaccination against a viral infection. A likely explanation is that the virus or another substance somehow triggers the immune system to attack the body’s own tissues ( Autoimmune Disorders ). The autoimmune reaction results in inflammation, which damages the myelin sheath and the nerve fiber under it. Multiple Sclerosis (MS) is the most common primary demyelinating disorder. 