Numbness

Numbness of the face, body or extremities (arms and legs) is one of the most common symptoms of MS. Often it’s the first symptom experienced by those eventually diagnosed with MS. The numbness may be mild or so severe that it interferes with the ability to use the affected body part. For example, a person with very numb feet may have difficulty walking. Numb hands may prevent writing, dressing, or holding objects safely.

Caution Advised Regarding Eating and Hot Objects

People with MS who have severe facial numbness should be very careful when eating or chewing, as they may unwittingly bite the inside of their mouth or tongue. People with numbness over other parts of the body should be careful around fires, hot water and other sources of heat, as they may suffer a burn without realizing it.

There are no medications to relieve numbness. Fortunately, however, most instances of numbness are not disabling, and tend to remit on their own. In very severe cases, a neurologist may prescribe a brief course of corticosteroids, which often can temporarily restore sensation.

What is Multiple Sclerosis?

Multiple sclerosis (or MS) is a chronic, often disabling disease that attacks the central nervous system (CNS), which is made up of the brain, spinal cord, and optic nerves. Symptoms may be mild, such as numbness in the limbs, or severe, such as paralysis or loss of vision. The progress, severity, and specific symptoms of MS are unpredictable and vary from one person to another. Today, new treatments and advances in research are giving new hope to people affected by the disease.

MS is Thought to be an Autoimmune Disease

The body’s own defense system attacks myelin, the fatty substance that surrounds and protects the nerve fibers in the central nervous system. The nerve fibers themselves can also be damaged. The damaged myelin forms scar tissue (sclerosis), which gives the disease its name. When any part of the myelin sheath or nerve fiber is damaged or destroyed, nerve impulses traveling to and from the brain and spinal cord are distorted or interrupted, producing the variety of symptoms that can occur.

Most people with MS learn to cope with the disease and continue to lead satisfying, productive lives.

The Four Courses of MS

People with MS can typically experience one of four disease courses, each of which might be mild, moderate, or severe.

• Relapsing-Remitting MS
  People with this type of MS experience clearly defined attacks of worsening neurologic function. These attacks—which are called relapses, flare-ups, or exacerbations —are followed by partial or complete recovery periods (remissions), during which no disease progression occurs. Approximately 85% of people are initially diagnosed with relapsing-remitting MS.
• Primary-Progressive MS
  This disease course is characterized by slowly worsening neurologic function from the beginning—with no distinct relapses or remissions. The rate of progression may vary over time, with occasional plateaus and temporary minor improvements. Approximately 10% of people are diagnosed with primary-progressive MS.
• Secondary-Progressive MS
  Following an initial period of relapsing-remitting MS, many people develop a secondary-progressive disease course in which the disease worsens more steadily, with or without occasional flare-ups, minor recoveries (remissions), or plateaus. Before the disease-modifying medications became available, approximately 50% of people with relapsing-remitting MS developed this form of the disease within 10 years. Long-term data are not yet available to determine if treatment significantly delays this transition.
• Progressive-Relapsing MS
  In this relatively rare course of MS (5%), people experience steadily worsening disease from the beginning, but with clear attacks of worsening neurologic function along the way. They may or may not experience some recovery following these relapses, but the disease continues to progress without remissions.

Since no two people have exactly the same experience of MS, the disease course may look very different from one person to another. And, it may not always be clear to the physician—at least right away—which course a person is experiencing.

For more important information about MS, check out Just the Facts (.pdf)

Diagnosing MS

At this time, there are no symptoms, physical findings, or laboratory tests that can, by themselves, determine if a person has MS. The doctor uses several strategies—including a careful medical history, a neurologic exam, and various tests—to determine if a person meets the long-established criteria for a diagnosis of MS and to rule out other possible causes of whatever symptoms the person is experiencing.

The Criteria for a Diagnosis of MS

In order to make a diagnosis of MS, the physician must:

• Find evidence of damage in at least two separate areas of the central nervous system (CNS), which includes the brain, spinal cord, and optic nerves AND
• Find evidence that the damage occurred at different points in time—at least one month apart AND
• Rule out all other possible diagnoses

In 2001, the International Panel on the Diagnosis of Multiple Sclerosis updated the criteria to include specific guidelines for using magnetic resonance imaging (MRI), visual evoked potentials (VEP), and cerebrospinal fluid analysisto speed the diagnostic process. These tests can be used to look for a second area of damage in a person who has experienced only one attack (also called a relapse or an exacerbation) of MS-like symptoms—referred to as a clinically-isolated syndrome (CIS). A person with CIS may or may not go on to develop MS.

The criteria were further revised in 2005 (now referred to as The Revised McDonald Criteria) to make the process even easier and more efficient.

The Tools for Making a Diagnosis

Medical History and Neurologic Exam

The physician takes a careful history to identify any past or present symptoms that might be caused by MS and to gather information about birthplace, family history, and places traveled that might provide further clues. The physician also performs a variety of tests to evaluate mental, emotional, and language functions, movement and coordination, vision, balance, and the functions of the five senses.

In many instances, the person’s medical history and neurologic exam provide enough evidence to meet the diagnostic criteria. Other tests are used to confirm the diagnosis or provide additional evidence if it’s necessary.

MRI

MRI is the best imaging technology for detecting the presence of MS plaques or scarring (also called lesions) in different parts of the CNS. It can also differentiate old lesions from those that are new or active.

The diagnosis of MS cannot be made solely on the basis of MRI because there are other diseases that cause lesions in the CNS that look like those caused by MS. And even people without any disease—particularly the elderly—can have spots on the brain that are similar to those seen in MS.

Although MRI is a very useful diagnostic tool, a normal MRI of the brain does not rule out the possibility of MS. About 5% of people who are confirmed to have MS do not initially have brain lesions on MRI. However, the longer a person goes without brain or spinal cord lesions on MRI, the more important it becomes to look for other possible diagnoses.

• Read more on MRI

Visual evoked potential (VEP)

Evoked potential (EP) tests are recordings of the nervous system's electrical response to the stimulation of specific sensory pathways (e.g., visual, auditory, general sensory). Because damage to myelin (demyelination) results in a slowing of response time, EPs can sometimes provide evidence of scarring along nerve pathways that does not show up during the neurologic exam. Visual evoked potentials are considered the most useful for confirming the MS diagnosis.

• Read more on visual evoked potentials

Cerebrospinal fluid analysis

Analysis of the cerebrospinal fluid, which is sampled by a spinal tap, detects the levels of certain immune system proteins and the presence of oligoclonal bands. These bands, which indicate an immune response within the CNS, are found in the spinal fluid of about 90-95% of people with MS. But because they are present in other diseases as well, oligoclonal bands cannot be relied on as positive proof of MS.

• Read more on celebrospinal fluid analysis

Blood tests

While there is no definitive blood test for MS, blood tests can rule out other conditions—including Lyme disease, a group of diseases known as collagen-vascular diseases, certain rare hereditary disorders, and AIDS—that cause symptoms similar to those of MS.

Other Conditions Cause Demyelination (Damage to Myelin)

• Demyelination in the Central Nervous System
  Although MS is the most common, other conditions can damage myelin in the CNS, including viral infections, side effects from high exposure to certain toxic materials, severe vitamin B12 deficiency, autoimmune conditions that lead to inflammation of blood vessels (the "collagen-vascular diseases"), and some rare hereditary disorders.
• Demyelination in the Peripheral Nervous System
  Demyelination of the peripheral nervous system (the nerves outside the brain and spinal cord.) occurs in Guillain-Barré Syndrome. After some injuries, the myelin sheath in the peripheral nervous system regenerates, bringing recovery of function.

Some demyelinating conditions are self-limiting, while others may be progressive. Careful (and sometimes repetitive) examinations may be needed to establish an exact diagnosis among the possible causes of neurologic symptoms.

In the United States today, there are approximately 400,000 people with multiple sclerosis (MS)—with 200 more people diagnosed every week. Worldwide, MS is thought to affect more than 2.5 million people. While the disease is not contagious or directly inherited, epidemiologists—the scientists who study patterns of disease—have identified factors in the distribution of MS around the world that may eventually help determine what causes the disease. These factors include gender, genetics, age, geography, and ethnic background.

Who gets MS?

In the United States today, there are approximately 400,000 people with multiple sclerosis (MS)—with 200 more people diagnosed every week. Worldwide, MS is thought to affect more than 2.5 million people. While the disease is not contagious or directly inherited, epidemiologists—the scientists who study patterns of disease—have identified factors in the distribution of MS around the world that may eventually help determine what causes the disease. These factors include gender, genetics, age, geography, and ethnic background.