What is Multiple Sclerosis? What is MS?

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Main Category: Multiple Sclerosis
Also Included In: Neurology / Neuroscience;  Rehabilitation / Physical Therapy
Article Date: 22 Apr 2009 - 18:00 PDT

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The term Multiple Sclerosis comes from the Latin multus plus plica meaning "fold", and the Greek sklerosis meaning "hardening". According to MediLexicon's medical dictionary, Multiple Sclerosis (MS) is a "common demyelinating disorder of the central nervous system, causing patches of sclerosis (plaques) in the brain and spinal cord; occurs primarily in young adults, and has protean clinical manifestations, depending on the location and size of the plaque; typical symptoms include visual loss, diplopia, nystagmus, dysarthria, weakness, paresthesias, bladder abnormalities, and mood alterations; characteristically, the plaques are "separated in time and space" and clinically the symptoms show exacerbations and remissions".

With MS the central nervous system (CNS) is attacked by the person's own immune system. That is why MS is known as an auto-immune disease. The CNS includes the brain, spinal cord and optic nerves.

Nerve fibers are surrounded by myelin, which protects the nerve fibers. Myelin also helps conduct electrical signals, also termed impulses - i.e. myelin facilitates a good flow of electricity along the nervous system from the brain.

The myelin of a patient with MS disappears in several areas (multiple areas). This leaves a scar (sclerosis). Multiple Sclerosis means Scar Tissue. The areas where there is either not enough or no myelin are called plaques or lesions. As the lesions get worse the nerve fiber can break or become damaged.

When a nerve fiber has less myelin the electrical impulses received from the brain do not flow smoothly to the target nerve - when there is no myelin the nerve fibers cannot conduct the electrical impulses at all. The electrical impulses are instructions from the brain to carry out actions, such as to move a muscle. MS is the disability to get your body to do what your brain wants it to.

Who can develop Multiple Sclerosis?

• MS can affect people of all ages.


• It is more common among people aged from 20 to 50 years.


• More women develop MS than men.


• People of European descent are more likely to develop MS, compared to other people. However, people of all ancestries can get it.


• Although your genetic make-up can decide how much you are at risk, experts say there is no proof that susceptibility is inherited.


• In 2007 the World Health Organization (WHO) estimated that approximately 2.5 million people had MS.

What Are the Causes of MS?

Although experts are still uncertain, most of them say that the person's own immune system attacks the myelin as if it were an undesirable foreign body - in the same way our immune system might attack a virus or bacteria.

Why might our immune system attack the myelin?

The reasons could be:

• Genetic
• Environmental
• Exposure to a toxic substance, such as a heavy metal

It is unlikely there is just one trigger, experts say, but rather MS is probably triggered by multiple factors.

What are the Symptoms of MS?

Symptoms generally appear between the ages of 20 and 40. Some patients experience such mild symptoms that they do not notice anything until much later in the course of the disease. Others may experience dramatic symptoms early on.

The most common symptoms are:

• Bladder Dysfunction
• Bowel Dysfunction
• Cognitive Function
• Depression
• Dizziness and Vertigo
• Emotional Changes
• Fatigue
• Numbness
• Pain
• Sexual Dysfunction
• Spasticity
• Vision Problems
• Walking (Gait), Balance, & Coordination Problems

These symptoms are less common, but also possible:

• Headache
• Hearing Loss
• Itching
• Respiration / Breathing Problems
• Seizures
• Speech Disorders
• Swallowing Problems
• Tremor

As the MS advances these symptoms may appear:

• Alterations in perception and thinking
• Fatigue
• Heat sensitivity
• Muscle spasm
• Sexual dysfunction

MS is an unpredictable disease. Each patient will experience it in different ways and symptoms will vary according to the person. For some, MS starts with a single symptom, and it could take months and even years without any MS progression being noticed. For others, however, symptoms worsen much more rapidly - within weeks or months.

A patient should not compare his/her symptoms with other patients'. Although a wide range of symptoms are possible, patients may experience some and never others. With some people, a symptom may occur once and never return - but not for others. MS is very much an individual disease.

The four courses of Multiple Sclerosis

There are 4 courses of the disease. In each case, the MS may be mild, moderate or severe.

• Relapsing-Remitting MS
  
  The patient experiences clearly-defined attacks of worsening neurologic function. These relapses are followed by remission (complete recovery periods). During the remission there is no disease progression. Other terms for relapses are flare-ups, or exacerbations. About 85% of MS patients are thought to have Relapsing-Remitting MS.
  
  
• Primary-Progressive MS
  
  The patient experiences slowly worsening neurologic function from the beginning. There are no distinct relapses or remissions. The rate at which the MS progresses will vary over time. The patient will experience periods of temporary minor improvements. This type of MS is thought to affect about 10% of all MS patients.
  
  
• Secondary-Progressive MS
  
  Initially it looks as though the patient has relapsing-remitting MS. However, the patient develops a secondary-progressive disease course in which the MS worsens more steadily. There may, or may not be intermittent relapses, remissions, or periods of temporary minor improvements.
  
  50% of patients with relapsing-remitting MS used to go on to develop this form of the disease within a decade before disease-modifying drugs became available. How long the new drugs may hold off the progression remains to be seen.
  
  
• Progressive-Relapsing MS
  
  The patient experiences steadily worsening symptoms right from the start. There are clear attacks of worsening neurologic function along the way. The MS continues to progress without remissions - there might be some recovery after relapses. Only 5% of MS patients have this type.

How is MS diagnosed?

Unfortunately, it is still not currently possible to diagnose MS by sending samples to a lab or collecting physical findings. The doctor needs to use several strategies to decide whether a patient meets the criteria for an MS diagnosis. To do this the doctor must eliminate other possible causes of the patient's symptoms. This will include looking at the patient's medical history, carrying out a neurologic exam, an MRI scan (magnetic resonance imaging), visual evoked potentials (VEP), spinal fluid analysis, and some other tests.

The health care professional needs to do the following before diagnosing MS:

• Detect evidence of damage in two or more separate parts of the CNS (central nervous system). The CNS includes the spinal cord, brain and optic nerves.
and

• Have proof that the CNS damage happened at least one month apart
and

• Eliminate other potential diagnoses

In 2001, the International Panel on the Diagnosis of Multiple Sclerosis revised the criteria to include precise instructions for using magnetic resonance imaging (MRI), visual evoked potentials (VEP) and cerebrospinal fluid analysis to hasten the diagnostic process. These tests can be used to look for a second area of damage in a person who has experienced only one episode of MS-like symptoms - referred to as a clinically-isolated syndrome (CIS). A person with CIS might not develop MS. The criteria were revised again in 2005 - it is now known as The Revised McDonald Criteria, and has improved the process.

What are the treatments for MS

There is no cure for MS yet. Existing treatments focus on suppressing the autoimmune response and managing symptoms. Some MS patients do not need treatment because their symptoms are so mild, while others do.

The most common drugs used for treating MS

• Corticosteroids - these drugs reduce inflammation. During a MS relapse inflammation can become problematic. Corticosteroids are the most commonly prescribed drugs for MS patients. Prednisone can be taken orally while methylprednisolone is administered intravenously. During a relapse there is a breakdown of the blood-brain-barrier (BBB) - harmful substances from the bloodstream might cross this barrier and make their way to the brain and spinal cord. Steroids stabilize the BBB and help prevent harmful substances leaking through. These drugs are also immunosuppressive - they help stop our body's immune system from attacking itself.


• Interferons - these medicines seem to slow down the progression of worsening MS symptoms. However, they must be used with care as they can also cause liver damage. Interferon alpha is used for treating some cancers, but has no effect on multiple sclerosis. Interferon gamma was also found to have no beneficial effect on multiple sclerosis. However, interferon beta has shown effectiveness as a multiple sclerosis treatment. While the exact method by which interferon beta 1a achieves its beneficial effects in multiple sclerosis remains unknown, some researchers believe it may reduce inflammation. Studies looking at how interferon beta behaves in the lab suggest it may stop harmful cells from entering the brain. This theory has not been tested in people.


• Copaxone (Glatiramer) - this drug is aimed at stopping the immune system from attacking myelin. It is a combination of four amino acids (proteins). It is injected once a day, subcutaneously (under the skin). The patient may experience flushing and shortness of breath after receiving the injection.


• Tysabri (Natalizumab) - this drug is used on patients who either cannot tolerate other treatments or did not experience any benefits from them. It increases the patient's chances of developing multifocal leukoencephalopathy, a fatal brain infection. The drug is believed to work by reducing the ability of inflammatory immune cells to attach to and pass through the cell layers lining the intestines and blood-brain barriers.


• Mitoxantrone (Novantrone) - usually used only for patients with advanced MS. It is an immunosuppressant medication that can damage the heart. Novantrone was approved for the treatment of some cancer about 15 years ago. MS patients may find the idea of using chemotherapy cancer treatment disconcerting. In 2000 the Food and Drug Administration (FDA) approved Novantrone as the "only treatment for worsening MS". The recommended treatment schedule for Novantrone usage in MS is much less intensive than for cancer treatment. For MS patients whose illness is rapidly progressing and getting worse despite other therapies, Novantrone can help slow down the progression of disability and help preserve the patient's independence.

Rehabilitation

Rehabilitation is designed to help the MS patient improve or maintain his/her ability to perform effectively at home and at work. The focus is on general fitness and energy management, while at the same time dealing with the problems related to mobility and accessibility, speech and swallowing, memory, thinking and perception.

For an MS patient to achieve good quality health care, rehabilitation is usually a crucial component.

Rehabilitation programs generally include:

• Physical therapy (UK term is physiotherapy) - aims to provide people with the skills to maintain and restore maximum movement and functional ability.


• Occupational therapy - The therapeutic use of work, self-care, and play activities to increase development and prevent disability. It may include adaptation of task or environment to achieve maximum independence and to enhance the quality of life (American Occupational Therapy Association).


• Speech and swallowing therapy - professionals who are trained to assess speech and language development and to treat speech and language disorders are called Speech Language Pathologists, or Speech Therapists. They are also trained to help people with swallowing disorders.


• Cognitive rehabilitation - assists in the management of specific problems in thinking and perception. The patient learns and practices skills and strategies to improve function and/or make up for deficits that remain.


• Vocational rehabilitation - helps people with disabilities make career plans, learn job skills, get and keep a job.

Plasma exchange (plasmapheresis)

Plasmapheresis involves withdrawing whole blood from the patient. The plasma is removed from the blood and replaced with new plasma. Then the blood, with all its red and white blood cells is transfused back into the patient. This process is effective in treating patients with autoimmune diseases because it takes out the antibodies in the blood that are attacking parts of the patients body they should not be attacking.

However, whether plasmapheresis is of benefit to MS patients is unclear. Studies using plasmapheresis on patients with primary and secondary progressive MS have had mixed results.

MS and life expectancy

The lifespan of a person with MS is usually about the same as a healthy person who does not have MS. In rare cases the MS may be so malignant that it is terminal.

News on Multiple Sclerosis

For the latest news and research on MS, please visit our Multiple Sclerosis news section.

Written by - Christian Nordqvist

Original article date: 10 February 2006
Article updated: 22 April 2009



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