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The Allergy Epidemic

A mere generation ago, asthma was one of those rare chronic illnesses that most parents just whispered about, solid foods were given in the first weeks of life, and eczema was a sign of aging skin. Now it seems every home with a baby has a nebulizer in the bathroom cabinet, solids are often delayed until 6 months of age, and infant eczema is as common as cradle cap.

Allergies are one of the fastest growing chronic diseases in childhood. Consider this: In recent decades, rates of eczema in the United States have tripled and those of asthma have nearly doubled. One in 20 children under age 3 now has a food allergy.

What's behind these sky-rocketing statistics? Strangely enough, we may be too darn clean: Some experts link the increase to improved hygiene, immunizations, and antibiotics that have dramatically reduced the number of diseases that threaten our bodies. As a result, the immune system -- which normally protects the body -- overreacts to harmless substances, such as pollen, mold, pet dander, or food. When exposed to these "allergens," the body responds with symptoms like swelling, hives, and itching.

The uptick in allergy rates may also be due to lifestyle changes: As Americans spend more time indoors, their exposure to allergens such as pets and dust mites increases. A greater awareness and improved diagnosis may play a role as well.

Having allergies early in life increases a child's risk for developing other related conditions, like hay fever, later on. What's more, tending to an allergic infant can give you a case of the crankies, too  -- nursing moms may be forced to forego favorite foods, for instance, and slathering skin softeners on squirmy babies just adds another level of complication to an already exhausting childcare routine.

While babies with a family history are at greatest risk, (a child has a 25 percent chance of having allergies if one parent is affected, and a 60 to 70 percent chance if both parents are), increasing numbers of babies without a family history are developing allergies. The good news is that there are ways to minimize your child's risk, spot the earliest signs, and keep symptoms under control, if your baby turns out to be one of the countless affected.

Food Allergies

A true allergic reaction -- when the body forms antibodies against allergens  -- is different and more severe than an adverse reaction to food, such as lactose intolerance, when the body has trouble digesting dairy products. While approximately 6 to 8 percent of babies will have a food allergy by a year of age, many will have outgrown them by the time they're 4 to 5 years old.

Cause:

Six foods cause 90 percent of food allergies in children: dairy, eggs, peanuts, tree nuts (such as pecans and walnuts), soy, and wheat. A breastfed baby can develop a food allergy if she's exposed to an allergen (such as cow's milk or peanuts) via breast milk. Her mom can continue nursing as long as she eliminates the allergy-causing food from her own diet.

Symptoms:

Signs of a food allergy include a rash around the face, hives, vomiting, diarrhea, trouble breathing, or swelling of the mouth and throat. The reaction usually occurs within a few minutes of eating the suspect food and can range from a mild rash to life-threatening anaphylaxis, which can cause breathing complications and loss of consciousness. Severe reactions are usually due to nut or fish allergies, and these are seldom outgrown.

An allergy to cow's milk proteins -- from formula or breast milk -- is common in the first year of life. Babies with a milk allergy are more likely to later develop hay fever or asthma. Many infants who are allergic to cow's milk-based formula are also allergic to soy-based formula and will need a hypoallergenic one.

Diagnosis:

Skin or blood tests can help pinpoint a child's food allergy. The results are not always easy to interpret, however, as positive results can occur without a true allergy. You may be asked to keep a chronological food diary for a few weeks, in which you write down everything your baby eats (and that you eat, if you're nursing) and any symptoms that you notice. Another method involves avoiding a suspect food for about two weeks, and then reintroducing it at the doctor's office where emergency care is available.

Treatment:

The first step is to eliminate the offending food from your child's diet -- not so easy when you consider how many foods contain milk, eggs, or wheat, for instance. Favorites like pasta, pizza, and mac 'n cheese can become immediate no-no's. Shopping and meal preparation take longer as well if you have to wade through labels and recipes to spot hidden ingredients. By January 2006, however, manufacturers will be required to clearly label the presence of allergens in food products.

You'll also need to inform friends, relatives, and caregivers about your child's food allergy, and be prepared for an accidental exposure. Antihistamines can be given to treat symptoms, and if a severe reaction has occurred in the past, your pediatrician may prescribe epinephrine that you can administer if there's an emergency.

Prevention:

If you or your partner have allergies, you can lower your baby's risk by breastfeeding (if it's possible) and using a hypoallergenic formula if you're supplementing. Your pediatrician may recommend that you avoid eating common food allergens, such as milk or nuts, during breastfeeding. The American Academy of Pediatrics also recommends delaying the age at which certain foods are introduced into your child's diet: Cow's milk, wheat, and soy should be delayed for at least one year; egg white for two years; and fish, shellfish, and peanut butter for three years. (Nuts should be avoided until age 4 because they're a choking hazard.) Your doctor may even suggest that you avoid eating peanuts during pregnancy.

Even if your baby doesn't have a family history, breastfeeding can reduce the risk of allergies, as can delaying the introduction of egg white, wheat, and cow's milk until your baby turns 1, and peanut butter and shellfish until age 2. To learn more, contact The Food Allergy & Anaphylaxis Network at 800-929-4040 or www.foodallergy.org.

Eczema

Eczema, also known as atopic dermatitis, is a common, chronic skin problem that causes intense itching and inflammation, and is characterized by flare-ups. Eczema affects about 17 percent of children, with 60 percent of cases beginning in the first year of life and 85 percent beginning by age 5.

Cause:

In infants and young children, eczema is often an early sign of allergy problems, and 75 percent of affected children will go on to develop another form of allergy, such as asthma or hay fever. Often, eczema outbreaks are waning or have completely disappeared by the time respiratory allergy symptoms surface. In 25 percent of cases in young children, eczema is triggered by food allergies, such as milk or egg white. It has also been linked with the early introduction of solids to a baby's diet (before the standard 4 to 6 months of age).

Certain airborne allergens, such as dust mites and animal dander, can make eczema worse. Other triggers include: excessively dry skin (from low humidity, frequent washing, or harsh soaps); restrictive or wool clothing; fabric softeners; overheating and sweating; or saliva from drooling. While eczema occurs more often in babies with a family history, about 20 percent of children with eczema don't have a related food allergy or a family history.

Symptoms:

Eczema has been called "an itch thatrashes" because itching is such a prominent symptom and the inevitable scratching further damages and inflames the skin. In babies, eczema typically begins as a dry, crusty rash on the cheeks and spreads behind the ears and to the scalp and body, usually sparing the diaper area. Infants may try to relieve the itching by rubbing their face against the crib sheet, irritating the skin. When a baby's skin is broken by scratching, bacteria and other germs on the skin surface can cause an infection. Fortunately, symptoms tend to improve as a child gets older, and in many infants, eczema has cleared completely by the time they're 3 to 5 years old.

Diagnosis:

Children with eczema often have high blood levels of the antibody involved in allergic reactions. Sometimes skin or blood tests are performed to identify food allergens that can aggravate the condition.

Treatment:

The toughest part of treating eczema is to break the destructive "itch-scratch" cycle that just makes it worse. Applying moisturizing creams frequently is your best bet here. When giving your baby a bath, use only mild soaps or non-soap cleansers. To prevent the skin from drying out, apply a thick moisturizer to the whole body immediately after patting your child dry.

Loose-fitting, 100 percent cotton clothing is recommended, including long-sleeved pajamas to prevent nighttime scratching. Use laundry products free of dyes and perfumes, and wash new clothes before your child wears them. Double-rinse clothing, towels, and bedding. While daily maintenance takes extra time, it's easier than treating a flare-up.

Your baby's doctor may also suggest that you eliminate a suspected food, such as milk or eggs, or try a low-allergenic diet for seven to ten days to see if symptoms improve.

If itching is severe enough to disturb sleep, applying cool, wet washcloths at bedtime can help. If necessary, a sedating antihistamine can be prescribed to help your baby sleep. When skin is inflamed, topical steroids may be given to reduce swelling. (These medications are given only for flare-ups because they can cause side effects when used too frequently.) Two new non-steroid, topical anti-inflammatory medications, Elidel and Protopic, have recently been approved by the Food and Drug Administration for use on children aged 2 and up, and studies suggest that these are safe for babies as young as 3 months.

If your child's skin becomes infected, oral or topical antibiotics can clear the infection and improve the skin condition. Keep your child's fingernails clean and short to prevent scratching and introducing bacteria.

Prevention:

Mothers of eczema-prone infants can reduce their baby's risk by breastfeeding and avoiding allergenic foods in their own diet. If you supplement breastfeeding, use a hypoallergenic formula. The risk of eczema is also reduced by delaying the introduction of allergenic foods in a baby's diet. To learn more, contact the National Eczema Association for Science and Education (800-818-7546).

Asthma

Asthma is a chronic respiratory condition in which the tubes that carry air in and out of the lungs (the bronchi) become inflamed and narrowed. Among children who develop asthma, nearly half show their first symptoms before age 1. About 70 to 80 percent of children with asthma also have allergies -- especially to airborne allergens such as animal danders, pollens, and dust mites. For these babies, allergens can trigger asthma flare-ups. Keep in mind that asthma doesn't come and go  -- the bronchial tubes are not only abnormal during an acute asthma attack, but remain inflamed and oversensitive during symptom-free periods as well.

Cause:

Certain triggers, such as pollen, respiratory viruses, or tobacco smoke, can cause the bronchial tubes to narrow. This tightening is made worse by inflammation, a thickening of the muscles lining the tubes, and an increased production of mucus.

Rates of asthma have dramatically increased in infants and toddlers, and while the reason is not known for certain, factors that are suspected to play a role include: exposure to cigarette smoke, air pollution, and pet dander; early entry into childcare (which brings an increased exposure to viral illnesses); an early end to breastfeeding; and infection with respiratory syncytial virus. Other culprits include cockroaches and dust mites. A history of asthma and/or allergy in a parent, especially the mother, is the greatest predictor of asthma in a baby.

Symptoms:

An acute asthma attack creates cough and congestion, rapid or difficult breathing, and a whistling noise when exhaling. A baby may be anxious and restless and struggling to breathe. Between acute bouts, she may cough frequently, especially at night.

Diagnosis:

Wheezing in an infant may simply be due to "reactive airways," rather than true asthma. Because infant and toddler airways are extra sensitive, they become narrowed easily, for example, during a respiratory illness or when exposed to cigarette smoke. In fact, only one third of infants who have bouts of wheezing in their first year will go on to have asthma in later childhood.

If your baby is coughing or wheezing, her doctor will likely first try to rule out medical conditions besides asthma. Skin and blood tests may be helpful in identifying any related allergies. You may be asked to keep a diary of your baby's symptoms for several weeks to try to identify asthma triggers in your child. About 70 percent of children with asthma are sensitive to cat or dog allergens. Sadly, parents may need to find a new home for the family pet.

Treatment:

Children with asthma usually require both daily "controller" medications, to reduce bronchial inflammation, and "rescue" treatment medications (known as bronchodilators), to quickly relax and widen the bronchial tubes during asthma attacks. In babies, medication can be given by a nebulizer that converts liquid medicine into a fine mist, an inhaler with a face mask, or oral syrup.

Children at greatest risk for severe asthma attacks are those whose disease is not well-controlled on a daily basis. Ask your child's doctor to provide you with a written instruction plan. Since asthma flare-ups are often triggered by related allergies, reducing your baby's exposure to irritants such as tobacco smoke, air pollution, or cold winter air can be a big help.

Prevention:

In addition to breastfeeding and avoiding tobacco smoke, it may be possible to delay or prevent asthma in high-risk infants by using air conditioning to keep airborne allergens to a minimum, not having a furry pet; and eliminating dust catchers like stuffed animals and drapes in your child's room. Since the influenza virus is a strong asthma trigger, an annual flu vaccine, beginning at 6 months of age, can help prevent acute attacks. To learn more, contact The American Academy of Allergy, Asthma, & Immunology (800-822-2762) or the The Allergy and Asthma Network/Mothers of Asthmatics (800/878-4403).

BabyTalk contributing editor and pediatrician Marianne Neifert, M.D., is the author of Dr. Mom's Guide to Breastfeeding.

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