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Diseases

Genetic and Rare Diseases Information Center (GARD)

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Multiple sclerosis

*

* Not a rare disease

Other Names for this Disease

  • MS
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

Overview

What is multiple sclerosis (MS)?

What are the signs and symptoms of multiple sclerosis?

What causes multiple sclerosis?

How is multiple sclerosis diagnosed?

What is multiple sclerosis (MS)?

Multiple sclerosis (MS) is a disorder that affects the central nervous system (CNS), specifically the brain and spinal cord. A fatty tissue called myelin surrounds and protects the nerve fibers of the CNS. Myelin insulates the nerves and allows them to transmit electrical impulses from the brain to other parts of the body. In MS, myelin is lost in multiple areas, and sometimes the nerve fiber itself is damaged or broken. When myelin or the nerve fiber is destroyed or damaged, the nerve’s ability to conduct electrical impulses to and from the brain is disrupted; therefore, nerve signals cannot be transmitted. The disruption of the electrical impulses causes the symptoms associated with MS. [1]
Last updated: 6/24/2013

What are the signs and symptoms of multiple sclerosis?

The peak age of onset is between ages 20 and 40, although it may develop in children and has also been identified in individuals over 60 years of age. The most common signs and symptoms include sensory disturbance of the limbs; partial or complete visual loss; acute and subacute motor dysfunction of the limbs; diplopia (double vision); and gait dysfunction. These signs and symptoms may occur alone or in combination, and have to be present for a minimum of 24 hours to be considered a "clinical attack." The signs and symptoms in individuals with MS are extremely variable, even among affected relatives within families.[2] Symptoms vary because the location and severity of each attack can be different. Episodes can last for days, weeks, or months. These episodes alternate with periods of reduced or no symptoms (remissions). While it is common for the disease to return (relapse), the disease may continue to get worse without periods of remission. Because nerves in any part of the brain or spinal cord may be damaged, patients with multiple sclerosis can have symptoms in many parts of the body.[3]

Muscle symptoms may include loss of balance, muscle spasms, numbness or abnormal sensation in any area, problems moving arms or legs, problems walking, problems with coordination and making small movements, and tremor or weakness in one or more arms or legs. Bowel and bladder symptoms may include constipation and stool leakage, difficulty beginning to urinate, frequent need or strong urge to urinate, and incontinence. Eye symptoms may include double vision, eye discomfort, uncontrollable rapid eye movements, and vision loss. There may be numbness, tingling, or pain in the face, muscles, arms or legs. Other brain and nerve symptoms may include decreased attention span, poor judgment, and memory loss; difficulty reasoning and solving problems; depression or feelings of sadness; dizziness and balance problems; and hearing loss. Individuals may also have slurred or difficult-to-understand speech, trouble chewing and swallowing, and sexual symptoms such as problems with erections or vaginal lubrication.[3]
Last updated: 3/30/2011

What causes multiple sclerosis?

Although the exact cause of MS is unknown, it is believed to be an autoimmune disorder, where the body’s immune system attacks the myelin.It is unclear what triggers the autoimmune response resulting in MS. However, the most frequent theories about the cause of MS include a virus-type organism, an abnormality of the genes responsible for control of the immune system, or a combination of both factors. [4]
Last updated: 6/24/2013

How is multiple sclerosis diagnosed?

Symptoms of MS may mimic those of many other nervous system disorders. The disease is a clinical diagnosis,[2] and is typically diagnosed by ruling out other conditions. A health care provider may suspect MS if there are decreases in the function of two different parts of the central nervous system (such as abnormal reflexes) at two different times (referred to as dissemination in time and space).[2][3] Dissemination in time and space is commonly used criteria for diagnosing relapsing-remitting MS (RR-MS). Dissemination in time means that there are at least two clinical attacks, each lasting at least 24 hours, separated by at least one month, or a slow, stepwise progressive course for at least six months. Dissemination in space means that there are lesions in more than one area or functional system of the brain or spinal cord white matter. For primary progressive MS (PP-MS), there are currently no diagnostic criteria that are universally accepted.[2]

Physicians may perform a variety of tests to evaluate an individual suspected of having MS. A neurological exam may show reduced nerve function in one area of the body, or spread over many parts of the body. This may include abnormal nerve reflexes, decreased ability to move a part of the body, decreased or abnormal sensation, and other loss of nervous system functions. An eye examination may show abnormal pupil responses, changes in the visual fields or eye movements, decreased visual acuity, problems with the inside parts of the eye, and rapid eye movements triggered when the eye moves. Other specific tests to diagnose multiple sclerosis may include lumbar puncture (spinal tap) for cerebrospinal fluid tests; MRI scan of the brain and MRI scan of the spine; nerve function study; and a variety of blood tests.[3]
Last updated: 3/30/2011

References
  1. What is Multiple Sclerosis?. National MS Society Web site. August 3, 2006; http://www.nationalmssociety.org/site/PageServer?pagename=HOM_ABOUT_what_is_ms. Accessed 1/7/2008.
  2. Olaf Stüve, Jorge Oksenberg. Multiple Sclerosis Overview. GeneReviews. May 11, 2010; http://www.ncbi.nlm.nih.gov/books/NBK1316/. Accessed 3/30/2011.
  3. David Zieve. Multiple Sclerosis. PubMed Health. August 5, 2010; http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001747/. Accessed 3/30/2011.
  4. Multiple Sclerosis. . MedlinePlus Medical Encyclopedia Web site. : http://vsearch.nlm.nih.gov/vivisimo/cgi-bin/query-meta?v%3Aproject=medlineplus&query=multiple+sclerosis. Accessed 1/7/2008.


Other Names for this Disease
  • MS
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.