Multiple
Sclerosis.
Summary
of Key Points
Multiple
Sclerosis is a very complex disease.
The incidence is
between 1: 2,000 and 1: 10,000 depending on geographic location (temperate or
tropics, respectively). This disease is one of young adults. Average age of
onset is 29-33 years. Twice as common in women than men. One of most common
diseases of CNS and is an inflammatory demyelinating condition. It interferes
with the smooth, rapid and coordinated muscular (limb) movement. Primary or
secondary progressive only likely conditions covered.
Primary MS is
characterised though by lack of distinct attacks. Slow onset and steadily
worsening symptoms. Accumulation of deficits. Occurs in about 15% MS sufferers.
Secondary is initially relapsing-remitting MS. Development of progressive
disability later. Often superimposed with relapses. About 40% of cases. Both
primary and secondary MS may not easily fit a description - lack of distinct
attacks but will an "attack" last 6 months or more? Probably -
primary is steadily worsening symptoms. Secondary is initially
relapsing-remitting so an "attack" is likely to come and go so can be
used as a symptom of a pre-existing condition. This excludes the 40% and leaves
the 15% possible.
Early MS may
present as history of vague symptoms. May be transitory and vague and confusing
to both doctor and patient. Doctor may not say MS is suspected. The course is
unpredictable. There is no typical MS, it is a clinical diagnosis and no
specific test (100% conclusive) for it. The type of symptom, onset and pattern
may suggest MS. Some symptoms are common to all sufferers but although most
will experience more than one symptom no person would have them all. Some are
immediately obvious (optic neuritis) but some are less so - fatigue, altered sensation,
memory and concentration. Many of the signs - identical abnormalities - could
be attributed to a number of medical conditions. These abnormalities in nerve
pathways but could not conclude cause of abnormality.
Other causes must
be eliminated (PD/MND/Alzheimer's Disease). Several tests and procedures are
needed to establish a diagnosis of MS. This may include lumbar puncture to test
the cerebrospinal fluid for antibodies and MRI to give pictures of scarring
evidence of brain and spinal cord (only test to see such lesions) but this is
only a significant indicator and not conclusive. These scars appear in
different areas of brain and spinal cord at different times.
Primary
symptoms
pain
á
trigeminal neuralgia (facial pain)
á
tightness around joints (low back pain)
á
paralysis (similar to stroke) - can be PTD
á
loss of vision (optic neuritis) - can be PTD
changes in eye
movements
á
involuntary rapid eye movement (nystagmus)
á
double vision (diplopia) - blurring of vision
á
total loss of sight (rare)
á
opsoclonus ("jumping vision") a related eye disorder
tremor -
uncontrollable shaking. Can occur in various parts of body
á
intention tremor is shaking when at rest
á
postural tremor is limb or whole body supported against gravity
co-ordination
á
ataxia (unstable walking)
á
loss of balance -
weakness
á
vertigo (giddiness, common symptom)
á
clumsiness of limb
bladder and
bowel dysfunction
á
urination often and/or urgently
á
incomplete emptying at inappropriate times
á
constipation
á
loss of bowel control sensation
numbness
á
parathesia ("pins and needles")
á
burning feeling in an area of body
á
sensitivity to heat (commonly exacerbates symptoms)
Abnormalities
may also include
á
slurred speech
á
loss of speech
á
changes in rhythm swallowing (dysphagia)
á
mostly advanced stages reflexes
fatigue
á
debilitating and general cognitive function (about 50% will develop some
cognitive dysfunction - 50% won't)
á
ability to think
concentration
á
judgment
á
reason
á
remembering
strength
á
particularly affect legs so walking problems
spasticity
á
mobility
á
walking spasms
á
involuntary muscle stiffness or spasms (wide range)
sexuality
á
impotence
á
diminished arousal
á
loss of sensation
Note that 50%
will not develop cognitive dysfunction. Optic neuritis may not affect vision
but MS may result. Optic neuritis also does not always develop into MS. About
50-60% do so 40-50% don't. But MS is still the most likely cause. Neurological
deficits indicate at least two different areas of CNS and occur at two separate
times, at least one month between, and persisting for 24 hours. A neurologist
would want to witness at least two distinct episodes. Note that CII requirement
is for "attack" to persist for 6 months so it is progressive types of
MS only. Ignore both benign and relapse-remitting and so probably secondary
progressive as this is how it starts. May develop into secondary but will be
compromised by pre-existing condition clause. The "5 year rule" -
first 5 years probably indicate how disease will continue but after 5-10 years
more reliable indicator.
This is the
explicit definition that must be primary progressive only - slow deterioration
of neurological function without remission - 15% cases. It demonstrates the
huge window, maybe as far back as 15 years into the medical history, to Òfind a
pre-existing symptomÓ. Will become severely disabled but life expectancy is
near normal. Over 55 years of age (in mostly males) at onset more likely to be
a faster, more progressive course.