Diseases & Conditions

Nervous System Disorders

Multiple Sclerosis

What is multiple sclerosis (MS)?

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Multiple sclerosis (MS) is a chronic disease of the central nervous system. It is thought to be an autoimmune disorder. It is an unpredictable condition that can be relatively benign, disabling, or devastating. Some individuals with MS may be mildly affected, while others may lose their ability to see clearly, write, speak, or walk when communication between the brain and other parts of the body becomes disrupted.

Myelin is a fatty tissue that surrounds and protects the nerve fibers. Myelin is lost in multiple areas with MS. This loss of myelin forms scar tissue called sclerosis. These areas are also called plaques or lesions. When damaged in this way, the nerves are unable to conduct electrical impulses to and from the brain.

What causes multiple sclerosis?

There are many possible causes of MS, including the following:

  • Autoimmune disorders

  • Infectious agents, such as viruses

  • Environmental factors

  • Genetic factors

However, not enough is known about the role these factors play to definitively describe why a particular patient develops MS.

What are the symptoms of MS?

The symptoms of MS are erratic. They may be mild or severe, of long duration or short. They may appear in various combinations, depending on the area of the nervous system affected. The following are the most common symptoms of MS. However, each individual may experience symptoms differently. Symptoms may include:

  • Initial symptoms of MS
    The following are often initial symptoms of MS:

    • Burred or double vision

    • Red-green color distortion

    • Pain and loss of vision due to optic neuritis, an inflammation of the optic nerve

    • Difficulty walking

    • Paresthesia. This refers to an abnormal sensation, or pain, such as numbness, prickling, or "pins and needles."

  • Other symptoms of multiple sclerosis
    Throughout the course of the illness, an individual may experience any or all of the following symptoms, to a varying degree:

    • Muscle weakness in the extremities

    • Difficulty with coordination. Impaired walking or standing may result; partial or complete paralysis is possible.

    • Spasticity. The involuntary increased tone of muscles leading to stiffness and spasms.

    • Fatigue. This may be triggered by physical activity, but may subside with rest; constant, persistent fatigue is possible.

    • Loss of sensation

    • Speech impediments

    • Tremor

    • Dizziness

    • Hearing loss

    • Bowel and bladder disturbances

    • Depression

    • Changes in sexual function


    Approximately 50 percent of all people with MS experience cognitive impairments related to their disease. The effects of these impairments may be mild, often detectable only after comprehensive testing, and may include difficulty with any or all of the following:

    • Concentration

    • Attention

    • Memory

    • Poor judgment

Symptom categories of MS

Primary symptoms. A direct result of demyelination, the destruction of myelin (the fatty sheath that surrounds and insulates nerve fibers in the central nervous system) may result in the following:

  • Weakness

  • Numbness

  • Tremor

  • Loss of vision

  • Pain

  • Paralysis

  • Loss of balance

  • Bladder and bowel dysfunction

Secondary symptoms. Complications that arise as a result of the primary symptoms, for example:

  • Paralysis can lead to bedsores.

  • Bladder dysfunction may cause repeated urinary tract infections.

  • Inactivity can result in weakness, poor postural alignment and trunk control, muscle imbalances, decreased bone density, and/or shallow, inefficient breathing.

  • Becoming less mobile because of weakness and difficulty swallowing can lead to an increased risk of pneumonia.

Tertiary symptoms. The social, vocational, and psychological complications of the primary and secondary symptoms, for example:

  • A person who becomes unable to walk or drive may lose his or her livelihood.

  • Strain of dealing with a chronic neurological illness may disrupt personal relationships.

  • Depression is often seen among people with MS.

The symptoms of MS may resemble other medical conditions or problems. Always consult your doctor for a diagnosis.

How is multiple sclerosis diagnosed?

With today's medicine, there is no definitive test available to diagnose multiple sclerosis. However, a probable diagnosis can be made by following a careful process which demonstrates findings that are consistent with MS, that also rule out other causes and diseases.

What are the two criteria used when diagnosing MS?

  1. There must have been two attacks at least one month apart. An attack is a sudden appearance of or worsening of any MS symptom or symptoms that lasts at least 24 hours.

  2. There must be more than one area of damage to the central nervous system myelin, the sheath that surrounds and protects nerve fibers, which must have occurred at more than one point in time and was not caused by any other disease.

More commonly nowadays, a single attack together with certain patterns of changes in brain tissue seen on a magnetic resonance image (MRI) of the brain (see the description of this below) can strongly suggest the diagnosis of MS.

What does an evaluation for MS cover?

Evaluation for MS involves a complete medical history and neurological exam, which includes:

  • Mental functions

  • Emotional functions

  • Language functions

  • Movement and coordination

  • Vision

  • Balance

  • Functions of the five senses

Evaluation procedures for MS

The following may be used when evaluating for multiple sclerosis:

  • Magnetic resonance imaging (MRI). A diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body; to detect the presence of plaques or scarring caused by MS.

  • Evoked potentials. Procedures that record the brain's electrical response to visual, auditory, and sensory stimuli; to show if there is a slowing of messages in the various parts of the brain.

  • Cerebral spinal fluid analysis (also called spinal tap or lumbar puncture). A procedure used to make an evaluation or diagnosis by examining the fluid withdrawn from the spinal column; to check for cellular and chemical abnormalities associated with MS.

  • Blood tests. These are done to rule out other causes for various neurological symptoms.

Evaluation and diagnosis of MS requires a variety of tools to rule out other possible disorders and a series of laboratory tests that, if positive, confirms the diagnosis.

Treatment for MS

Specific treatment for MS will be determined by your doctor based on:

  • Your age, overall health, and medical history

  • Extent of the disease

  • Your tolerance for specific medications, procedures, or therapies

  • Expectations for the course of the disease

  • Your opinion or preference

Treatments for the conditions associated with MS may include the following:

  • Medication

  • Clinical trials

  • Assistive technology

  • Rehabilitation activities

There is no cure yet for MS. However, there are strategies to modify the disease course, treat exacerbations, manage symptoms, and improve function and mobility.

Rehabilitation for people with MS

Rehabilitation varies depending on the range, expression, severity, and progression of symptoms. MS rehabilitation may help to accomplish the following:

  • Restore functions that are essential to the activities of daily living (ADLs)

  • Help the patient to reach maximum independence

  • Promote family involvement

  • Empower the patient to make the appropriate decisions relating to his or her care

  • Educate the patient regarding the use of assistive devices (for example, canes, braces, or walkers)

  • Establish an appropriate exercise program that promotes muscle strength, endurance, and control

  • Reestablish motor skills

  • Improve communication skills for patients who have difficulty speaking because of weakness or incoordination of face and tongue muscles

  • Manage bowel or bladder incontinence

  • Provide cognitive retraining

  • Adapt the home environment to emphasize function, safety, accessibility, and mobility

Online Medical Reviewer: Petersen, Sheralee, MPAS, PA-C
Online Medical Reviewer: Sohrabi, Farrokh, MD
Last Annual Review Date: 6/30/2012
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