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All About Allergies
Dust, cats peanuts, cockroaches. An odd grouping,
but one with a common thread: allergies.
If you child has allergies, he is not alone. Up to
50 million Americans, including 2 million children,
have some type of allergy. For most people,
allergies are just an inconvenience. But according
to the National Institute for Allergy and Infectious
Disease, they are a major cause of disability in the
U.S. In fact, it has been estimated that allergies
account for the loss of over two million school days
per year.
What Are Allergies?
An allergy is an overreaction of the immune system
toward a substance that is typically harmless to
most people. But in someone with an allergy, the
body’s immune system treats the substance, called an
allergen, as an invader and reacts inappropriately
resulting in harm to the person.
In the most common type of allergy, at the most
common type of allergy, at the first exposure to an
allergen, the immune system produces an antibody
called immunoglobulin E (LgE).
In the most common type of allergy, at the first
exposure to an allergen, the immune system produces
an antibody called immunoglobulin E (lgE).
With each suvsequent exposure, the body produces
more lgE, which attaches itself to two types of
cells in the body called mast cells and basophils.
The allergen attaches to the lgE, and the mast cells
and basophils are activated to release histamine and
other chemicals to defend against the allergen
“invader” It is the release of these chemicats that
causes allergic reactions, as the body attempts to
rid itself of the invading allergen.
Some of the most common allergies include those to
food and to airborne allergens such as pollen, mold,
dust mites, and animal emanations. Allergies can be
seasonal, like dust mites. Regional differences also
occur since different allergens are more prevalent
in different parts of the country or the world. For
example, peanut allergy is unknown in Scandinavia,
where they do not eat peanuts, but common in the
U.S., where the per capita consumption of peanuts is
about 8 pounds a year.
Who Gets Allergies? Children inherit allergic
tendencies from their parents. A few children have
allergies in spite of no family member having these,
but if one parent has allergies, there is a one in
four chance that a child will also have allergies.
The risk increases if both parents have allergies.
Allergies also tend to develop in multiple
substances. If a child is allergic to one substance,
it is likely that he will be allergic to others as
well. There are also children who suffer from
cross-reactions. For example, children who are
allergic to birch pollen might have reactions when
they eat an apple because that apple is a protein
similar to the pollen.
Another example is children who are allergic to
latex (as in gloves or certain types of hospital
equipment) are more likely to be allergic to kiwi
fruit or bananas.
Symptoms of Allergies: The type and severity of
allergy symptoms vary from allergy to allergy and
child to child. Some children may experience a
combination of symptoms.
Airborne allergens can cause sneezing, itchy nose
and/or throat, nasal congestion, and coughing; this
is known as allergic rhinitis. These symptoms are
often accompanied by itchy, watery, and/ or red
eyes, which is called allergic conjunctivitis, or
when dark circles are present around the reddened
eyes, allergic “shiners.”
The symptoms of allergic rhinitis and conjunctivitis
can range from minor or major seasonal annoyances to
yearround problems. If they occur with wheezing and
shortness of breath, the allergy may have progressed
to become asthma, which can be a serious condition.
In children with food allergies, some only exhibit “
oral allergy syndrome” an itchy mouth and throat
when food is ingested. Others develop a rash or
cramping accompanied by nausea and vomiting or
diarrhea, as the body attempts to flush out the
irritant. Other common allergic symptoms of allergic
food reactions are hives. Runny, itchy nose, and in
more severe cases, shortness of breath.
Severity of food allergies and when they develop
depends on the quantity of the food eaten, the
amount of exposure the child has had, and the
child’s sensitivity to the food.
Common foods that may cause allergies include cow’s
milk, soy, egg, wheat, seafood, tree nuts (such as
walnuts and pistachios), and peanuts.
Peanuts are one of the most severe food allergens,
often causing life threatening reactions, (In rare
instances, if the sensitivity to an allergen is
extreme, a child may develop a life- threatening
condition called anaphylactic shock. Severe symptoms
or reactions to any allergen require immediate
medical attention. Fortunately, severe of life-
threatening allergies occur only in a small group of
children.)
Does My Child Have an Allergy?
Some allergies are fairly easy to identify because
the pattern of symptoms following certain exposures
can be hard to miss. But other can masquerade as
other conditions.
If your child has cold-like symptoms lasting longer
than a week or two or develops a “cold” at the same
time every year, consult your child’s doctor. He or
she will likely ask questions about the nature of
the symptoms and when they appear. Based on the
answers to these questions and a physical exam, your
child’s doctor may be able to make a diagnosis and
prescribe medications or may refer you to an
allergist for allergy skin tests and more extensive
therapy.
How Are Allergies Treated? There is no cure for
allergies, but symptomatic relief is possible. The
most effective is by reducing or eliminating
exposure to allergens. If reducing exposure is not
feasible or is ineffective, medications may be
prescribed. In some cases, an allergist may
recomment immunotherapy (allergy shots) to help
desensitize your child. There are also medications
your might be able to give your child, including
antihistamines and inhaled or nasal spray steroids . |