Allergies
Asthma
Skin,
and Hair
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Dust, cats, peanuts, cockroaches. An odd grouping, but one with a common thread: allergies.
If your 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 first exposure to an allergen, the immune system produces an antibody called immunoglobulin E (IgE). With each subsequent exposure, the body produces more IgE, which attaches itself to two types of cells in the body called mast cells and basophils. The allergen attaches to the IgE, 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 chemicals 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 emantions. Allergies can be seasonal, like pollen or certain molds, or year-round, 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 year-round 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 or 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 allergies are less obvious because they 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 recommend immunotherapy (allergy shots) to help desensitize your child. There are also medications you might be able to give your child, including antihistamines and inhaled or nasal spray steroids.
Food allergies are usually not lifelong (although those to peanut, tree nut, and seafood can be). Avoiding the food is the only way to avoid symptoms while the
sensitivity persists. If a child is extremely sensitive to a particular food, or if the child has asthma in addition to the food allergy, his doctor will probably recommend that you carry injectable epinephrine or adrenaline to counteract the allergic reaction in the event of an inadvertent exposure.
More Information
Airborne allergens
Those who react to airborne allergens usually have allergic rhinitis and/or allergic conjunctivitis. Allergic rhinitis occurs in about 15-20% of Americans. It typically develops by age 10 and reaches its peak in the early 20s, with symptoms often dissipating between the ages of 40 and 60.
Dust mites are one of the most common causes of allergies and are present year-round in most parts of the U.S., although they do not live at high altitudes. Dust comprises many particles and can contain things such as fabric fibers and bacteria, as well as microscopic dust mites and animals allergens (ex. cats). The dust mite is the main allergic component of house dust. Dust mites live in bedding, upholstery, and carpets. Cockroach body parts and waste products are also a major household allergen, especially in inner cities. Asthma rates of inner city children are high, probably due to air pollution and also cockroach exposure in overcrowded buildings.
Pollen is another important cause of allergies. Trees, weeds, and grasses release these tiny particles into the air to fertilize other plants. Most people know pollen allergy as hay fever or rose fever. Pollen allergies are seasonal, and the type of pollen a child is allergic to determines when he will be symptomatic. For example, in the mid-Atlantic states, tree pollination begins in February and March, grass from May through June, and ragweed from August through October.
Pollen counts measure how much pollen is in the air. Pollen counts are usually higher in the morning and on warm, dry, breezy days; they are lowest when it is chilly and wet. Although they are not exact, the local weather report's pollen count can be helpful when planning outside activities.
Molds are fungi that thrive both indoors and out in warm, moist environments. As with pollen, mold spores are released into the air to reproduce. Outdoors, molds may be found in poor drainage areas, such as in piles of rotting leaves or compost piles; indoors they thrive in dark, poorly ventilated places, such as bathrooms and closets. Mold buildup may be found in damp basements or basements with water leaks. A musty odor suggests mold growth. Although molds can be seasonal, many thrive year-round, especially those indoors.
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