Multiple sclerosis (MS) is a disease that causes demyelination (disruption of the myelin that insulates and protects nerve cells) of spinal nerve and brain cells.

• Although the exact case is unknown, multiple sclerosis is considered to be an autoimmune disease.
• Risk factors for the disease include being between 15-45 years of age; women have about two to three times the risk for multiple sclerosis than men.
• Multiple sclerosis symptoms and signs depend on where the nerves are demyelinated and may include
  • visual changes,
  • numbness,
  • tingling or weakness (weakness may range from mild to severe),
  • paralysis,
  • vertigo,
  • erectile dysfunction (ED, impotence)
  • pregnancy problems,
  • incontinence (or conversely, urinary retention),
  • muscle spasticity,
  • painful involuntary muscle contractions.
• There are four types of multiple sclerosis:
  • relapsing-remitting multiple sclerosis (RRMS,
  • the most common type), secondary-progressive multiple sclerosis (SPMS),
  • primary-progressive multiple sclerosis (SPMS), and
  • progressive-relapsing multiple sclerosis (PRMS).
• Multiple sclerosis is diagnosed by a patient's history, physical exam, and tests such as MRI, lumbar puncture, and evoked potential testing (speed of nerve impulses); other tests may be done to rule out other diseases that may cause similar symptoms.
• Multiple sclerosis treatment options include
  • IV steroids,
  • interferon injections (Rebif),
  • glatiramer acetate (Copaxone),
  • dimethyl fumarate (Tecfidera), and
  • many others, depending on the patient's symptoms.

  Learn more about: Rebif | Copaxone | Tecfidera

• Most multiple sclerosis patients have a normal life expectancy; untreated patients may develop mobility dysfunction while patients with the severe progressive forms may develop complications like pneumonia.
• Ways to prevent getting multiple sclerosis have not been discovered.
• Research is ongoing into developing new medications, immune system modifications, and other ways to identify potential multiple sclerosis causes.

Multiple sclerosis definition

Multiple sclerosis is a disease that involves an immune-mediated process that results in an abnormal response in the body's immune system that damages central nervous system tissues; the immune system attacks myelin, the substance that surrounds and insulate nerves fibers causing demyelination that leads to nerve damage. Because the exact antigen or target of the immune – mediated attack is not known, many experts prefer to label multiple sclerosis as "immune-mediated instead of an "autoimmune disease."

What is multiple sclerosis?

Multiple sclerosis is a disease which causes demyelination of the brain and spinal cord nerve cells. When this occurs, axons (the parts of the nerve cells which conduct impulses to other cells), don't work as well. Myelin acts like insulation on electrical wires. As more areas or nerves are affected by this loss of myelin, patients develop symptoms because the ability of axons to conduct impulses is diminished or lost. The specific symptom that someone experiences is related to the area that has been affected. As demyelination takes place, areas of inflammation and subsequent injury can be identified; these areas of injury are called lesions or plaques and are readily apparent on magnetic resonance imaging (MRI) studies.

In multiple sclerosis, the protective coating on nerve fibers (myelin) in the central nervous system is damaged. This creates a lesion that, depending on the location in the central nervous system, may cause symptoms such as numbness, Pain or tingling in parts of the body.

Multiple sclerosis signs and symptoms may differ greatly from person to person and over the course of the disease depending on the location of affected nerve fibers. Symptoms often affect movement, such as:

• Numbness or Weakness in one or more limbs that typically occurs on one side of your body at a time, or your legs and trunk
• Electric-shock sensations that occur with certain neck movements, especially bending the neck forward (Lhermitte sign)
• Tremor, lack of coordination or unsteady gait

Vision problems are also common, including:

• Partial or complete loss of vision, usually in one eye at a time, often with Pain during eye movement
• Prolonged double vision
• Blurry vision

Multiple sclerosis symptoms may also include:

• Slurred speech
• Fatigue
• Dizziness
• Tingling or Pain in parts of your body
• Problems with sexual, bowel and bladder function

The cause of multiple sclerosis is unknown. It's considered an autoimmune disease in which the body's immune system attacks its own tissues. In the case of MS, this immune system malfunction destroys the fatty substance that coats and protects nerve fibers in the brain and spinal cord (myelin).

Myelin can be compared to the insulation coating on electrical wires. When the protective myelin is damaged and the nerve fiber is exposed, the messages that travel along that nerve fiber may be slowed or blocked.

It isn't clear why MS develops in some people and not others. A combination of genetics and environmental factors appears to be responsible.

• Many factors go into consideration for the treatment of a patient who has multiple sclerosis. During an acute exacerbation, steroids given through an IV are commonly prescribed, and often help patients recover more rapidly. If a patient cannot receive steroids, plasma exchange can be used.

  Once a diagnosis of multiple sclerosis has been confirmed, disease-modifying therapy is often recommended. This therapy may decrease the number of exacerbations that a patient experiences or decrease the severity of an exacerbation. In addition, many of these therapies have been shown to decrease the potential for developing long-term disability.

  Multiple sclerosis medications

  Interferon therapies

  Interferon therapies (Avonex, Betaseron, Extavia, Rebif, Plegridy) must be given by an injection. The frequency of injections ranges from every other day to every other week. Some patients develop flu-like symptoms or nodules under the skin following each injection; other patients may develop severe depression.

  Glatiramer acetate (Copaxone) works along a different path than the interferons, but is still thought to modify the immune system and has been shown to reduce relapses. There are some oral medications which have been approved to treat multiple sclerosis, including fingolimod (Gilenya) and teriflunomide (Aubagio).

  Although these medications are dosed orally, there is a risk of significant side effects:

  • including heart disease (fingolimod), or
  • severe liver injury (teriflunomide).

  Another oral agent, dimethyl fumarate (Tecfidera), may function by preventing immune cells from attacking cells located in the central nervous system, and may have anti-inflammatory properties.

  Dalfampridine (Ampyra), has been approved to specifically help with walking problems caused by multiple sclerosis. The specific way in which this medication works is unknown. There is a risk that this medication may cause seizures, even in patients without a history of seizure or epilepsy. As such, the use of this medication needs to be monitored carefully.

  Natalizumab (Tysabri) is a monoclonal antibody, and has been approved for patients who have relapsing-remitting multiple sclerosis. Because of significant side effects, including the risk of severe brain infection, it is typically used for patients who have failed to respond to one of the interferon products or who have been diagnosed with very active disease.

  Alemtuzumab (Lemtrada) can also decrease the relapse rate in relapsing-remitting multiple sclerosis. However, because of the risk of serious side effects, it is currently limited to use in patients who have failed other agents.

  Mitoxantrone (Novantrone) is a chemotherapy agent for leukemia or prostate cancer, which has been shown to be of benefit in treating secondary-progressive multiple sclerosis, progressive-relapsing multiple sclerosis, and advanced relapsing-remitting multiple sclerosis.

  Of note, mitoxantrone and Betaseron are the only medications identified to help patients with relapsing-primary multiple sclerosis.

These factors may increase your risk of developing multiple sclerosis:

• Age. MS can occur at any age, but onset usually occurs around 20 and 40 years of age. However, younger and older people can be affected.
• Sex. Women are more than two to three times as likely as men are to have relapsing-remitting MS.
• Family history. If one of your parents or siblings has had MS, you are at higher risk of developing the disease.
• Certain infections. A variety of viruses have been linked to MS, including Epstein-Barr, the virus that causes infectious mononucleosis.
• Race. White people, particularly those of Northern European descent, are at highest risk of developing MS. People of Asian, African or Native American descent have the lowest risk.
• Climate. MS is far more common in countries with temperate climates, including Canada, the northern United States, New Zealand, southeastern Australia and Europe.
• Vitamin D. Having low levels of vitamin D and low exposure to sunlight is associated with a greater risk of MS.
• Certain autoimmune diseases. You have a slightly higher risk of developing MS if you have other autoimmune disorders such as thyroid disease, pernicious anemia, psoriasis, type 1 diabetes or inflammatory bowel disease.
• Smoking. Smokers who experience an initial event of symptoms that may signal MS are more likely than nonsmokers to develop a second event that confirms relapsing-remitting MS.