Biology and Human Focus
This report includes the basic facts about Multiple Sclerosis. Treatments, effects
of treatments, symptoms, who MS affects, different types of MS, process of diagnosing
MS, Future treatments, and Pathophysiology are explained through the course of this
report. The course, at which this disease takes, once symptoms become obvious, is also
An unpredictable disease of the central nervous system, multiple sclerosis (MS)
can range from relatively benign to somewhat disabling to devastating, as communication
between the brain and other parts of the body is disrupted (NINDS). In 1868, Dr. Jean
Martin Charcot made the first diagnosis of MS. Many investigators believe MS to be an
autoimmune disease -- one in which the body, through its immune system, launches a
defensive attack against its own tissues. In the case of MS, it is the nerve-insulating
myelin that comes under assault. Such assaults may be linked to an unknown
environmental trigger, perhaps a virus (MSIF).
Most people experience their first symptoms of MS between the ages of 20 and
40; the initial symptom of MS is often blurred or double vision, red-green color
distortion, or even blindness in one eye. Most MS patients experience muscle weakness
in their extremities and difficulty with coordination and balance. These symptoms may
be severe enough to impair walking or even standing (NINDS).In the worst cases, MS
can produce partial or complete paralysis. Most people with MS also exhibit
paresthesias, transitory abnormal sensory feelings such as numbness, prickling, or "pins
and needles" sensations. Some may also experience pain. Speech impediments, tremors,
and dizziness are other frequent complaints. Occasionally, people with MS have hearing
loss (Better Health). Approximately half of all people with MS experience cognitive
impairments such as difficulties with concentration, attention, memory, and poor
judgment, but such symptoms are usually mild and are frequently overlooked.
Depression is another common feature of MS (NINDS). An estimated 2,500,000 people
around the world have multiple sclerosis. These people are generally:
• Young adults - symptoms first appear between the ages of 20 and 50 years.
• Female - 70 per cent of people with MS are female.
• Caucasian - 98 per cent of people with MS are Caucasian.
• Living in temperate zones - MS is generally more common between latitudes
40° and 60° north and south of the equator.
• Have a relative with MS - between 10 and 20 per cent of people with MS have a
relative with the disease, suggesting a genetic link (Better Health).
The cause of multiple sclerosis is not yet known, but thousands of researchers all
over the world are meticulously putting the pieces of this complicated puzzle together.
The damage to myelin in MS may be due to an abnormal response of the body's immune
system, which normally defends the body against invading organisms (bacteria and
viruses) (Multiple Sclerosis). Many of the characteristics of MS suggest an 'auto-immune'
disease whereby the body attacks its own cells and tissues, which in the case of MS is
myelin. Researchers do not know what triggers the immune system to attack myelin, but
it is thought to be a combination of several factors (MSIF).
One theory is that a virus, possibly lying dormant in the body, may play a major
role in the development of the disease and may disturb the immune system or indirectly
instigate the auto-immune process. A great deal of research has taken place in trying to
identify an MS virus. It is probable that there is no one MS virus, but that a common
virus, such as measles or herpes, may act as a trigger for MS. This trigger activates white
blood cells (lymphocytes) in the blood stream, which enter the brain by making
vulnerable the brain's defense mechanisms (i.e. the blood/brain barrier). Once inside the
brain these cells activate other elements of the immune system in such a way that they
attack and destroy myelin (MSIF).
In this form of MS there are unpredictable relapses (exacerbations, attacks) during which
new symptoms appear or existing symptoms become more severe. This can last for
varying periods (days or months) and there is partial or total remission (recovery). The
disease may be inactive for months or years.
• Frequency - approx 25% (MSIF)
After one or two attacks with complete recovery, this form of MS does not worsen with
time and there is no permanent disability. Benign MS can only be identified when there is
minimal disability 10-15 years after onset and initially would have been categorized as
relapsing-remitting MS. Benign MS tends to be associated with less severe symptoms at
onset (e.g. sensory).
• Frequency - approx 20% (MSIF)
Secondary Progressive MS
For some individuals who initially have relapsing-remitting MS, there is the development
of progressive disability later in the course of the disease often with superimposed
• Frequency - approx 40% (MSIF)
Primary Progressive MS
This form of MS is characterized by a lack of distinct attacks, but with slow onset and
steadily worsening symptoms. There is an accumulation of deficits and disability which
may level off at some point or continue over months and years.
• Frequency - approx 15% (MSIF)
Unlike many other diseases, there is no straightforward ‘positive or negative’ test
for MS and none of the range of tests available to help doctors with their diagnosis is
100% conclusive on its own. This means that ultimately a doctor will diagnose MS by a
combination of observing a person’s symptoms, and ruling out other possibilities. This is
called a ‘clinical diagnosis’ (Better Health).
Problems with diagnosis
Unfortunately for a significant minority of people (10 – 15 %) a definite diagnosis
is still not possible even after all the available tests have been carried out. However, it is
possible to rule out other very serious causes of MS type symptoms, and over time with
periodic examinations and the monitoring of changes in a person’s condition, diagnosis is
possible in the vast majority of cases (Multiple Sclerosis).
New MS Diagnostic Criteria
International Medical and Scientific Boards have drawn up new MS diagnostic
criteria to help medical professionals distinguish between MS and other conditions that
may present similar symptoms. The new criteria allow the results of MRI scanning to
include so that it may be possible to diagnose MS when someone has had only one
episode of symptoms. When the new criteria are used, a person may be classified as
having MS, possible MS or not MS (Multiple Sclerosis).
Early MS may present itself as a history of vague symptoms, which may occur
sporadically over a prolonged period of time and could often also be attributed to a
number of other medical conditions. Invisible or subjective symptoms are often difficult
to communicate to doctors and health professionals and sadly it has not been uncommon
for people with MS to be treated unsympathetically in the very early stages of diagnosis.
Even when a person shows a ‘classic’ pattern of MS type symptoms, the symptoms must
conform to agreed criteria before a doctor or neurologist can diagnose clinically ‘definite’
MS (Better Health). These criteria are that: ‘Two different areas of the central nervous
system are affected, and that these effects have been experienced on at least two separate
occasions of at least one month apart and that the person is within the normal age range
for the onset of MS’ So although it is possible to be diagnosed as having ‘definite’ MS on
your first visit to a neurologist, it is also quite likely that the diagnosis will be uncertain,
and that the person will be referred for further tests (Multiple Sclerosis).
Pathophysiology: MS is regarded as an autoimmune disease. Most of what is
known about MS is derived from its model in animal research, which is experimental
The auto antigen in MS most likely is one of several myelin proteins (e.g., proteolipid
protein [PLP], myelin oligodendrocyte glycoprotein [MOG], MBP). Microglial cells and
macrophages perform jointly as antigen-presenting cells, resulting in activation of
cytokines, complement, and other modulators of the inflammatory process, targeting
specific oligodendroglia cells and their membrane myelin.
The pathologic hallmark of MS is multicentric, multiphasic CNS inflammation and
demyelization. Originally, each MS lesion was thought to evolve through episodes of
demyelization and remyelination into a chronic burned-out plaque with relative
preservation of axons and gliosis. Thus, the neuropsychological dysfunction occurred,
despite an essentially intact neural network, until late in the disease course. However,
recent studies have demonstrated that axonal transactions do occur during acute
exacerbations; furthermore, axonal damage, as measured by magnetic resonance
spectroscopy, was found to correlate with clinical disability. Clearly, more work is
needed to understand the associations among inflammation-mediated demyelization,
axonal injury, and clinical disability.
For unclear reasons, lesions characteristically involve the optic nerve and periventricular
white matter of the cerebellum, brain stem, basal ganglia, and spinal cord. Identifying MS
lesions in gross specimens is difficult, as is identifying MS lesions in gray matter on
radiographic images; hence, the predilection for white matter may not be disease related.
The peripheral nervous system rarely is involved (Multiple Sclerosis).
There is as yet no cure for MS. Many patients do well with no therapy at all,
especially since many medications have serious side effects and some carry significant
risks. However, three forms of beta interferon (Avonex, Betaseron, and Rebif) have now
been approved by the Food and Drug Administration for treatment of relapsing-remitting
MS. Beta interferon has been shown to reduce the number of exacerbations and may slow
the progression of physical disability. When attacks do occur, they tend to be shorter and
less severe (NINDS). The FDA also has approved a synthetic form of myelin basic
protein, called copolymer I (Copaxone), for the treatment of relapsing-remitting MS.
Copolymer I has few side effects, and studies indicate that the agent can reduce the
relapse rate by almost one third. An immunosuppressant treatment, Novantrone
(mitoxantrone), is approved by the FDA for the treatment of advanced or chronic MS.
While steroids do not affect the course of MS over time, they can reduce the duration and
severity of attacks in some patients (Explaining). Spasticity, which can occur either as a
sustained stiffness caused by increased muscle tone or as spasms that come and go, is
usually treated with muscle relaxants and tranquilizers such as baclofen, tizanidine,
diazepam, clonazepam, and dantrolene. Physical therapy and exercise can help preserve
remaining function, and patients may find that various aids -- such as foot braces, canes,
and walkers -- can help them remain independent and mobile. Avoiding excessive
activity and avoiding heat are probably the most important measures patients can take to
counter physiological fatigue. If psychological symptoms of fatigue such as depression
or apathy are evident, antidepressant medications may help (Multiple Sclerosis). Other
drugs that may reduce fatigue in some, but not all, patients include amantadine
(Symmetrel), pemoline (Cylert), and the still-experimental drug aminopyridine. Although
improvement of optic symptoms usually occurs even without treatment, a short course of
treatment with intravenous methylprednisolone (Solu-Medrol) followed by treatment
with oral steroids is sometimes used (Explaining).
The two principle aims of drug therapy for MS are to ease specific symptoms and
hamper the progression of disease by shortening the attacks. The types of drugs used in
treatment depend on a number of factors, including the person's form of MS. Some of the
drug treatments available include:
• Immunotherapy - these drugs are taken in the form of subcutaneous (under the
skin) or intramuscular injection. These medications slow the frequency and
severity of attacks, which means the myelin sheaths are subjected to less damage.
Immunotherapy works by modifying the activity of the immune system. This
treatment is most often prescribed for people with relapsing–remitting MS.
• Methotrexate - usually taken orally. This drug is traditionally used to treat
rheumatoid arthritis, but recent research has discovered its effectiveness for
treating progressive MS. It is not in common use.
• Methylprednisolone - taken either as pills or injections. This cortisone-like drug
is used to control the severity of an MS attack, by easing inflammation at the
affected site (Multiple Sclerosis).
Side effects of drug treatment
The possible side effects of drug treatment depend on the medications used and
you should discuss any concerns with your doctor. Depending on the drug, side effects
• Gastrointestinal upsets
• Fluid retention
• Flu-like symptoms
• Skin irritation at the site of injection
• Mood altering effects (Multiple Sclerosis)
Treatment for specific symptoms
Treatments for specific symptoms may include a range of treatments, including:
• Muscle problems - a combination of drugs may ease muscle problems, including
stiffness and tremors. Physiotherapy is also recommended.
• Fatigue - some studies have found that drugs used to treat the sleep disorder
narcolepsy are helpful in controlling MS-related fatigue.
• Neurological symptoms - visual disturbances can be helped with drugs,
• Continence - treatment for continence problems may include special exercises,
medications, continence aids (such as disposable pads) and certain dietary
• Neuropsychological problems - treatment for depression or anxiety may include
counseling or medication. Memory problems and other cognitive difficulties can
be better managed with professional help from a neurophysiologist (Multiple
Health care providers
A person with MS can better manage their symptoms by drawing on the resources
of a health care team, including:
• Physiotherapy - including tailored exercise programs to improve strength,
coordination and flexibility.
• Occupational therapy - to learn coping strategies and new energy saving skills to
ensure a more independent life. These may include the use of aids.
• Neuropsychological therapy - including techniques to improve memory and
• Other therapies - as needed, such as speech therapists, eye specialists.
• Social workers (Multiple Sclerosis)
Medications and physical therapies can be complemented by alternative therapies.
See your health care provider for information, advice and possible referral. The ranges of
alternative therapies that may be helpful include:
• Biofeedback therapy
• Relaxation techniques
• Tai chi
• Yoga (NINDS)
The Course of MS
The course of MS is unpredictable. Some people are minimally affected by
the disease while others have rapid progress to total disability, with most people
fitting between these two extremes. Although every individual will experience a
different combination of MS symptoms there are a number of distinct patterns
relating to the course of the disease (MSIF). It is impossible to predict accurately the
course of MS for any individual, but the first five years give some indication of how
the disease will continue for that person. This is based upon the course of the disease
over that period and the disease type. The level of disability reached at end points
such as five and ten years is thought to be a reliable predictor of the future course of
the disease (Multiple Sclerosis).
The prospect of therapy for MS should be encouraging to those newly
diagnosed with MS. Drugs such as interferon beta are possible treatments for those
who are relapsing-remitting and ambulatory. The interferon betas may slow the
progression of disability as well as reduce the severity and frequency of
exacerbations. At this stage it is not known whether interferon beta has any impact on
primary progressive MS. The research currently targeting MS gives hope that therapy
which will interfere with the process of MS (even if not curing the disease) is not an
unreasonable expectation in the near future (Multiple Sclerosis). Other future or
experimental treatments include: Cannabis. Cannabis, the source of marijuana, has
been found to improve tremor and spasticity in animal studies. In one study of MS
patients, a third reported improvements in pain, spasms, tremor, mood, appetite,
fatigue, vision, sexual and urinary function, and memory. Cannabis may, however,
worsen balance and posture in patients with spasticity due to MS. Four studies of
cannabis used in capsules or in an oral spray are currently underway in England
(MSIF), and Stem Cell Transplantation. Some investigators are studying the benefits
of stem-cell transplantation procedures. Stem cells are produced in the bone marrow
and are the early forms for all blood cells in the body (including red, white, and
immune cells). Early studies indicate that it may slow progression, although at this
point it is not a cure (Explaining).
Since the cause of MS is still unknown how to prevent this disease is also
Better Health Channel. “Explaining Multiple Sclerosis.” May 25, 1999. 2005.
Explaining Multiple Sclerosis. December 12, 2002, 2005. < http://www.mult-
Multiple Sclerosis International Federation (MSIF). “Welcome to the World of Multiple
Sclerosis.” November 1, 2005. 2005.
National Institute of Neurological Disorders and Stroke (NINDS). October 13, 2005.