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FAMILIAL
MEDITERRANEAN FEVER
What
is it?
Familial Mediterranean fever (FMF) is a genetically disease. Patients
will suffer from recurrent bouts of fever, accompanied by abdominal,
chest, or joint pain and swelling. The disease generally affects
people of Mediterranean and Middle Eastern descent, that is Jews
(especially Sephardic), Turks, Arabs and Armenians.
How
common is it?
The frequency of the disease in high risk populations is about
one to three in 1000. It is rare in other parts of the world.
However, since the discovery of the associated gene, it is being
diagnosed more frequently, even among populations where it was
thought to be very rare, such as Italians, Greek and Americans.
FMF attacks start before 20 year of age in approximately 90% of
the patients. In more than half of them the disease appears in
the first decade of life. Boys are affected slightly more often
than girls (13:10).
What
are the causes of the disease?
FMF is a genetic disease. The responsible gene is called the MEFV
gene after Mediterranean fever and it affects a protein, which
plays a role in the natural resolution of inflammation. If this
gene carries a mutation, as in FMF, this regulation cannot be
done properly and the patients experience attacks of fever.
Is
it inherited?
It is inherited as an autosomal recessive disease (which means
that it is not linked to the gender and that neither parent needs
to show symptoms of the disease). This type of transmission means
that to have FMF one needs two mutated genes, one from the mother
and the other from the father. So both parents are carriers (a
carrier has only one mutated copy, but not the disease) rather
than patients. The disease in the extended family, for example,
is usually detected in a sibling, a cousin, an uncle or a far
relative. However, as seen in a small proportion of cases, if
one parent has FMF and the other is a carrier, there is a 50%
chance that their child will get the disease
Why
has my child got this disease? Can it be prevented?
The child has the disease because of the genes that cause FMF.
In approximately one fourth of patients, the parents are of the
same family tree (descendants of the same ancestors).
Is
it contagious?
No, it is not.
What
are the main symptoms?
The main symptoms of the disease are recurrent fever, accompanied
by abdominal, chest, or joint pains. Abdominal attacks are the
most common, seen in about 90% of patients. Attacks with chest
pain occur in 20-40%, and joint pain in 50-60% of the patients.
Usually children complain of a particular attack type, such as
recurrent abdominal pain and fever. Yet some patients experience
different attack types, one at a time or in combination
These attacks are self-limited (meaning that they resolve without
treatment) and last between one and four days. The patients recover
fully at the end of an attack and are totally normal in between
these bouts. Some of the attacks may be so painful that the patient
or family seeks medical help. Severe abdominal attacks may mimic
acute appendicitis and therefore some patients may undergo unnecessary
abdominal surgery, such as an appendectomy.
However, some attacks, even in the same patient, may be mild enough
to be confused with abdominal distress. This is one of the reasons
why it is hard to recognize these patients. During abdominal pain,
the child is usually constipated, but as the pain gets better,
soft stools appear.
The child can have very high fever during one attack and a mild
increase in temperatures in another. The chest pain usually only
affects one side, but it may be so severe that the patient cannot
breathe deeply enough. It resolves within days. Usually, only
one joint is affected at a time (monoarthritis). It is commonly
an ankle or a knee. It may be so swollen and painful that the
child cannot walk. In about a third of these patients there is
an erythematous rash over the involved joint. Joint attacks may
last somewhat longer than the other forms of attacks.
It can take from four days to two weeks before it resolves completely.
In some children, the sole finding of the disease may be recurrent
joint pain and swelling, which is misdiagnosed as acute rheumatic
fever, or juvenile idiopathic arthritis.
In about in 5-10% of cases joint involvement may become chronic
and cause irreversible changes. There is a characteristic rash
of FMF called erysipelas-like erythema, usually observed over
the lower extremities and joints. Some children may complain of
leg pains.
Among the rarer forms of attack are recurrent pericarditis (inflammation
of the outer layer of the heart), myositis (muscle inflammation),
meningitis (inflammation of the membrane surrounding the brain
and spinal cord) and orchitis (testicular inflammation).
Some diseases characterized by blood vessel inflammation (vasculitis)
are seen more frequently among children with FMF, such as Henoch-Schönlein’s
purpura and polyarteritis nodosa.
The most sever complication of FMF in untreated cases is the development
of amyloidosis.
Amyloid is a special protein that deposits in certain organs,
like the kidneys, gut, skin and heart and causes gradual loss
of function, especially of the kidneys. It is not specific for
FMF and it may complicate other chronic, inflammatory diseases
that are not properly treated, but finding amyloid in the gut
or kidney maybe a clue to diagnosis.
Children who are receiving a proper dose of colchicines (see drug
therapy) are safe from the risk of developing this life-threatening
complication.
Is the disease the same in every child?
It is not the same in every child. Moreover, the type, duration
and severity of attacks may be different each time, even in the
same child.
Is
the disease in children different from the disease in adults?
In general FMF in children resembles that seen in adults. However
some features of the disease like arthritis (joint inflammation)
and myositis are more common in childhood and their frequency
decrease as the patient gets older. Orchitis is detected more
often in young boys than adult males. The age of onset of FMF
is also important. The risk of amyloidosis is higher among untreated
patients with early disease onset.
How
is it diagnosed?
There is no specific tool for the diagnosis of FMF. Generally
the following approach is followed:
a) Clinical suspicion: It is possible to consider FMF only after
the child experience a minimum of three attacks. A detailed history
of the ethnic background should be considered, as well as relatives
with similar complaints, or renal insufficiency.
Also, the parents should be asked to give a detailed description
of previous attacks.
b) Follow-up: A child with suspected of having FMF should be followed
closely before a definite diagnosis is made. During this follow-up
period, if possible, the patient should be seen during an attack
for a thorough physical examination and for blood tests to look
for the presence of inflammation.
Generally, these tests become positive during an attack and go
back to normal, or near normal, after the attack subsides. There
are classification criteria designed to help in recognizing FMF,
which can be used at this stage of diagnosis.
It is not always possible to see a child during an attack for
various reasons. Then the parents are kindly asked to keep a diary
and describe what happens. They can also use a local laboratory
for blood tests.
c) Response to colchicine treatment: Children with clinical and
laboratory findings, which make the diagnosis of FMF highly probable,
are given colchicine for approximately six months to evaluate
the symptoms. If the patient has FMF, either there will be no
attacks, or the number, severity and duration of attacks will
be significantly less then expected.
Only after the above steps are completed can the patient be diagnosed
as having FMF and prescribed life-long colchicine.
As FMF affects a number of different systems in the body, various
specialists are involved in the diagnosis and management of FMF.
These are in general pediatricians, pediatric or adult rheumatologists,
nephrologists (kidney specialist) and gastroenterologists (digestive
system).
d) Genetic analysis: For the last couple of years, it has been
possible to perform a genetic analysis of patients to ascertain
the presence of mutations that are thought to be responsible for
the development of FMF
The clinical diagnosis of FMF is confirmed if the patient carries
2 mutations; one from each parent. However, the mutations that
have been described, so far, are found in about 70-80% of patients
with FMF. That means there are FMF patients with no mutations,
therefore, the diagnosis of FMF still depends on clinical judgement.
Genetic analysis may not be available in every treatment center.
Fever and abdominal pain are very common complaints in childhood.
Therefore, it is not easy to diagnose FMF, even in high-risk populations.
It takes a couple of years before it can be recognized. This delay
in diagnosis is very important, because of the increased risk
of amyloidosis in untreated patients.
There are a number of other diseases with recurrent bouts of fever,
abdominal and joint pain. The Majority of these diseases are also
genetic and share some common clinical features, however, each
has its own distinguishing clinical and laboratory characteristics.
What
is the importance of tests?
a) Blood tests: The laboratory tests, as mentioned before, are
important in diagnosing FMF. Tests like erythrocyte sedimentation
rate (ESR), CRP, whole blood count and fibrinogen are ordered
during an attack to see the extent of inflammation.
These are repeated after the child becomes symptom-free, to observe
if the results are back to normal, or near normal. In about a
third of patients, the tests go back to normal levels. In the
remaining two thirds, the levels decrease significantly, but remains
over the upper limit of normal.
A small amount of blood is also needed for the genetic analysis.
The children, who are on life-long colchicine treatment, have
to give some blood and urine twice a year for observational purposes.
b) Urine test: A sample of urine is also tested for the presence
of protein and red blood cells. There may be temporary changes
during attacks. Patients with amyloidosis will have persistent
levels of protein in urine tests. This warns the physician to
do more tests to see if this is secondary to amyloidosis.
c) Rectal or renal biopsy: Rectal biopsy is when a very small
piece of tissue is removed from the rectum and it is very easy
to perform. If the rectal biopsy fails to show amyloid, a renal
biopsy is necessary to confirm the diagnosis. For the renal biopsy
the child has to spend a night at the hospital. The tissues obtained
from the biopsy are stained and then examined for deposits of
amyloid.
Can
it be treated or cured?
It cannot be cured, but it can be treated with life-long use of
colchine. In this way, recurrent attacks and amyloidosis can be
prevented. If the patient stops taking the drug, the attacks and
the risk of amyloidosis come back.
What
are the treatments?
The treatment for FMF is simple, cheap and without any major drug
side-effects. Today Colchicine is the only drug that is used in
the treatment of FMF. After the diagnosis is made, the child has
to take the drug for the rest of his life. If taken properly,
the attacks disappear in about 60% of patients, a partial response
is obtained in 30%, but it is found to be ineffective in 5-10%
of patients.
This treatment not only controls the attacks, but also eliminates
the risk of amyloidosis. Therefore, it is crucial for the doctors
to explain to parents and the patient over and over again how
vital it is to take this drug in the dose prescribed. Compliance
is very important. If this is established, then the child can
live a normal life with a normal life-expectancy. The dose should
not be modified by the parents without consulting the physician.
The dose of colchicines should not be increased during an already
active attack, as such an increase is ineffective. The important
thing is to prevent attacks from coming.
What
are the side effects of drug therapy?
It is not easy for parents to accept that their child has to take
these pills forever. They are usually worried about the potential
side effects of colchicine. It is a safe drug with minor side
effects which usually respond to dose reduction. The most frequent
side effect is diarrhea.
Some children cannot tolerate the given dose because of frequent
watery stools. In these cases, the dose should be reduced till
it is tolerated and then slowly with small increments it should
be increased back to the appropriate dose.
Other side effects are nausea, vomiting, and abdominal cramps.
In rare cases, it may cause muscle weakness. The number of peripheral
blood cells (white and red blood cells and platelets) may decrease
occasionally, but recover with dose reduction.
A decrease in the number of sperms is very rare in treatment doses.
Female patients do not have to stop taking colchine during pregnancy
or breast-feeding.
How
long should treatment last for?
It is a life-long preventive treatment.
What
about unconventional or complementary therapies?
There is no such therapy.
What
kind of periodic check-ups are necessary?
Children being treated should have blood and urine tests for at
least twice yearly.
How
long will the disease last for?
It is a life-long disease.
What
is the long term prognosis (predicted outcome and course) of the
disease?
If treated properly with life-long colchicines, children with
FMF live a normal life. If there is a delay in diagnosis, or lack
of compliance with treatment, the risk of developing amyloidosis
increases, which is related to a poor prognosis. The children
who develop amyloidosis, may need a kidney transplant.
Growth retardation is not a major problem in FMF. In some children,
growth development at the time of puberty is recovered only after
colchicine treatment.
Is
it possible to recover completely?
No, because it is a genetic disease. However, life-long therapy
with colchicine gives the patient the opportunity to live a normal
life, without restrictions and with no risk of developing amyloidosis.
Everyday
life
How could the disease affect the child and family’s
daily life?
The child and the family experience major problems before the
disease is diagnosed. They have to take the child to a hospital
frequently because of severe abdominal, chest or joint pain. Some
children undergo unnecessary surgery due to misdiagnosis. After
the diagnosis is made, both the child and the parents lead an
almost normal life. Some even forget that the child has FMF. This
may be dangerous, because it can foster complacency with regard
to taking the colchicine.
The only problem may be the psychological burden of life-long
treatment. This can be overcome with patient-parent education
programs.
What
about school?
Frequent attacks cause problems with school attendance. After
the colchicine treatment is initiated, this is no longer a problem.
The teachers should be informed about the disease and what to
do in case an attack starts at school.
What
about sports?
The patients with FMF who are receiving life-long colchicine,
can do any sport they wish. The only problem can be protracted
joint inflammation, which may cause limitation of motion at affected
joints.
What
about diet?
There is no specific diet.
Can
climate influence the course of the disease?
No, it cannot.
Can
the child be vaccinated?
Yes, the child can be vaccinated.
What
about sexual life, pregnancy, birth control?
Patients with FMF do have fertility problems before colchicine
treatment, but after colchicine has been prescribed, this problem
disappears. The drug must be taken during pregnancy.

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