PEDIATRIC
MULTIPLE SCLEROSIS
Multiple sclerosis (MS)
is a disorder of the central nervous system.
Children and adolescents can develop
MS although usually it affects young and middle aged adults.
An estimated 2-3 % of patients with
MS are under age 18. It is rarely seen in the very young child,
and percentages increase with age.
MS
is now a treatable disease, with medications first introduced in
1993.
Multiple
sclerosis is defined as multiple episodes or “attacks” of CNS
demyelination dysfunction over time.
By definition, these events last at
least 24 hours.
These
attacks are caused by the disruption of the myelin coating of
the nerves of the brain and spinal cord.
(If
the nervous system is thought of as a telephone cord, we can
picture the disruption of the myelin as a break in the plastic
coating of the cord.
This break may interrupt the signals
being transmitted through the wire.
In the case of the telephone, it may
interrupt the conversation.
In MS, it may cause an “attack”.)
Often, the myelin is repaired, and
the symptoms will disappear or “remit”.
When another episode occurs, we can
call it a “relapse”.
The diagnosis
of MS is based on the clinical events.
There are tests that are used to aid
in the diagnosis.
These include:
-
Magnetic Resonance
Imaging (MRI)
-
Spinal fluid (Lumbar
Puncture) analysis
-
Blood work
-
Evoked potentials, or
tests of nerve and muscle function (including Visual Evoked
Potential-VEP, Brainstem Auditory Evoked Response- BAER,
Somatosensory Evoked Potential-SSEP, Nerve Conduction
Velocity-NCV).
These tests will help to rule out other
diseases, and confirm the diagnosis of MS.
Symptoms and Signs
The signs of MS depend
on the location of the disruption of myelin or “lesions”.
Initial symptoms can include:
-
optic neuritis (loss of vision which may affect one or both
eyes)
-
motor weakness
-
balance problems
-
sensory disturbance
-
loss of coordination
-
bladder dysfunction
-
problems related to brainstem involvement (facial numbness,
double vision).
For the
younger children, especially those under six, seizures, a change
in mental status , and a combination of the other symptoms may
be seen.
The MRI findings in the younger
child may be different from what is seen in adults.
Disease Course
Most of the cases of
Pediatric MS (93-98%) involve the Relapsing-Remitting type of
disease.
There are episodes of neurologic
symptoms or relapses which last at least 24 hours, and then go
on to stabilize or improve.
There may be residual deficits over
time.
Over time (sometimes decades) most
children with MS develop accumulated neurological impairments.
However this progression occurs more gradually in children than
in adults with the disease.
Less
commonly, kids with pediatric MS can have an aggressive course
and develop severe deficits during childhood
Over time,
most adults and children with MS will transition from the
relapsing remitting type, to gradual disease progression.
This is called secondary progressive
MS. During this time, patients gradually accumulate increasing
deficits.
A much less
common type of MS (estimated to occur in < 3%) is primary
progressive MS.
In this type, there are no relapses
and instead, patients follow a steadily progressive course. In
primary progressive MS symptoms and signs accumulate over time
and relapses never occur.
PROGNOSTIC FACTORS
It is extremely difficult to predict the
disease course in any one individual child or adult with MS.
Some individuals show minimal signs of the disease through-out
their course and experience few relapses. Others relapse
frequently and rapidly progress to requiring a wheel chair.
PSYCHOSOCIAL FEATURES
Most children with MS
have never met another child with MS.
Parents may feel isolated.
Information regarding the disease
and treatment may be hard to find.
However
there are programs for affected children and families.
It is not
uncommon for children with MS to at some point have difficulty
with depression or anxiety.
There is therapy available to help
with these problems.
School may be
affected by MS as well.
Severe
fatigue, cognitive (thinking) dysfunction,
and
physical changes related to the disease (such as missed school
days due to relapse, or problems like weakness or difficulty
writing) can make affected kids stand out from their peers.
However, most kids with MS will
graduate high school and go on to college and further studies.
Modifications can be
put in place within the school to enable affected children to
successfully complete their education.
These may include
-
extra time to take tests, or even shorter tests
-
a quiet environment for test taking
-
notes from the teacher
-
an extra set of books so that child does not have to carry
them to and from school
-
use of elevator in school
-
gym class can be modified to allow for participation as
tolerated
-
Educating the school professionals that the
relapsing-remitting nature of the disease may cause the
child to appear fine one day and too tired to participate
the next.
TREATMENT
While there are currently no medications
approved for treatment of pediatric MS, there are therapies that
are commonly used.
Treatment can be divided into treatment of
relapses and disease modifying therapies and symptomatic
treatment.
Treatment
of relapses
-
The first step in the management of a relapse is thorough
neurological evaluation.
-
Intravenous steroid therapy is often started with the goal
of decreasing the duration of the relapse and speeding
recovery of an acute relapse.
Treatment regimens vary from 3 to 5 days. Some
specialists may use a tapering dose of oral steroids after
the IV, others do not.
Steroids may have side
effects which include: irritability, insomnia, and increased
appetite.
These side effects will resolve
after the steroids are complete.
-
Intravenous immunoglobulin (IVIgG) may be used for children
who do not respond to steroid
therapy or who are unable to use steroids.
-
Plasmapheresis is another treatment that might be used for
children who do not respond to steroids.
This treatment is typically done in a hospital
setting and involves filtering the child’s blood to remove
the cells that may be causing the acute relapse.
Treatments are usually given every other day for a
total of 5 treatments.
The child may be able to undergo the treatment on an
out-patient basis.
Disease
modifying therapies
Disease modifying
therapies are the medicines that actually work to alter the
course of the disease.
These treatments have been shown to
be useful in relapsing remitting MS or in adults with a single
relapse who are at high risk for a subsequent event.
The medications are most effective in
decreasing the frequency and severity of relapses. To a lesser
degree the DMTs lessen the accumulation of neurological
impairments or disability.
Currently approved therapies
include (in order of their timing of FDA approval)
-
Betaseron (Interferon beta 1b) Subcutaneous injection three
times weekly, with an “autojector” device
-
Avonex (interferon
beta 1a) Intramuscular injection once weekly
-
Copaxone (glatiramer acetate)
Subcutaneous
injection daily, with an “autojector” device
-
Rebif (interferon
beta 1a) subcutaneous injection three times weekly, with an
“autojector” device
The interferons and
glatiramer acetate affect the immune system by slightly
different mechanisms. However, each of these therapies have
their own advantages and disadvantages, largely based on side
effects and convenience.
Natilizumab (Tysabri) and
mitoxantrone (Novantrone) are second line therapies which are
given intravenously. They are usually prescribed when first line
agents fail. Neither of these therapies are currently approved
for use in children.
Symptomatic therapy
Symptoms associate with MS vary, and treatment
is based on the individual.
-
Mood. The rate of
mood disorder and depression among with MS is high.
If not treated, they may worsen.
Antidepressant therapy and cognitive behavioral
therapy are recommended.
-
Painful spasms may be treated with medications such as
Baclafen and Tizanidine.
These medications may be used in conjunction with
exercise and physical therapy.
-
Fatigue is another very frequent problem. Fatigue is both
due directly to MS as well as a consequence of the
depression, sleep disturbance, and pain associated with the
disease. Management includes steps to conserve energy,
exercise and medication. Medications considered effective
and also found to be well tolerated in children include
amantadine and modafinil.
Ideally the
management of children with MS is multidisciplinary. In addition
to a neurologist, ideally familiar with MS in children,
professionals from physical therapy, neuropsychology, nursing,
and psychiatry are often needed to address the multiple issues
associated with the disease.
A recreational program for teens
with MS is available through the Teen Adventure Program. This
activity helps teens meet others their age in a pleasant
non-medical setting. As progress in the management of MS grows
affected individuals can expect
better and more convenient treatment options.
SUMMARY
Children and
adolescents can develop MS. Teens are affected more frequently
than younger children. The disease is almost always relapsing
remitting at onset and
treatable. Psychosocial
complications are frequent and likely result from changes
related to the disease itself, as the consequences of chronic
illness.
MS responds best to multidisciplinary
treatment including modifying the disease course with immune
modulating therapies and treating on-going symptoms such as mood
disorders.
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