Food Allergies in Children

Whenever we talk of allergies amongst children, we generally refer to the dust, mite, weather, pollen, and so on,i.e mostly the inhalant group of allergens.

Allergic manifestations in children generally present in the form of respiratory, skin and sometimes gastrointestinal manifestations.

In my practice I have seen many parents who come to me with these issues, but with a firm belief that the problem is because of dust, pollen, weather and so on, and they often resign to their fate saying that this is going to be like this. The first thing that I ask them is – What can you do about the dust or weather? The next question which then pops up is – Is there anything else which is exacerbating the symptoms? Here comes in the part of food allergies. Most of us do not even realize as to what all can be the food allergens and how significantly they can affect our lives. If you know your child is allergic to A or B and you stop those things from getting into his body then a lot of problems can be sorted out. Modern day medicine is now shifting more towards preventive rather than curative medicine.

What is allergy ?

Allergy refers to an acquired potential for developing adverse reactions that are immunologically mediated (via IgE antibodies), and allergic disease represent the clinical manifestations of these adverse immune responses

What are allergens ?

Allergens are often common, usually harmless, substances such as pollens, mold spores, animal danders, dust, foods, insect venoms, cockroaches, latex, and drugs. Allergens can induce IgE antibody responses.

What happens in food allergy? It may vary from very mild symptoms to very severe symptoms. Severe symptoms may mean anaphylactic reactions meaning if someone takes some food to which he is highly allergic then he may develop a swelling all over his body and may also have difficulty in breathing which may require immediate medical attention. The common form of allergies which we see is in the form of respiratory tract symptoms like wheeze, allergic cough, skin rashes, recurrent episodes of urticaria and so on. It has also been seen that if you find out the offending allergens and keep your child away from them, it can lead to significant resolution of some long standing physical symptoms.

Factors which affect food allergy :

Family history.

• Infants with one allergic parent have about twice the risk of developing food allergy than infants whose parents do not have allergies.
• If both parents are allergic, the risk increases four to six times.
• Breast Feeding
• Breast-feeding has been reported to reduce the risk of food allergy compared with formula-fed infants.
• For babies born into families where close relatives suffer from allergies, it seems that exclusive breast-feeding for 4-6 months may provide a degree of protection.

Delay solid food

Introduction of all solids should be delayed until after the age of 6 months.

Incidence of food allergy:

• 1-2% in adult population.
• Prevalence among young children- 3-7% ( European data).

Age wise prevalence of food allergy:

• Food allergy peaks at 1 year (6% to 8%) of age and then falls progressively
• In late childhood the prevalence is 4%.
• Most food allergy is acquired in the first 1 to 2 years of life.

When should you suspect a food allergy in your child?

If your child has a skin condition which is not healing or is recurring frequently, if your child is having repeated episodes of wheeze and cough, if your child is have gastrointestinal symptoms on and off which is not responding to conventional treatment then you may suspect a food allergy. One must remember that mere presence of the above mentioned symptoms do not indicate in that direction. What is important is to realize that when conventional treatment in terms of antihistaminics or respiratory stimulants or routine medicines is required much more frequently, one must think ‘outside the box’.

Methods of doing allergy screen :

Various methods are being used to do the allergy screen in both adults and children and their sensitivity and specificity varies accordingly.

1. Percutaneous and Intracutaneous (Intradermal) Testing
2. Intradermal Dilutional Testing (IDT) (also known as Skin Endpoint Titration [SET])
3. Leukocyte Histamine Release Test
4. Patch Test
5. Photo Patch Test
6. Total Serum IgE Concentration
7. Bronchial Challenge Test
8. Double-blind Food Challenge Test
9. IgG allergen levels
10. Specific IgE in Vitro Test (RAST, MAST, FAST, and ELISA)

The one which is commonly used is the Specific IgE in Vitro Test (ELISA). This test has an advantage that it requires only a blood sample to be taken. Its sensitivity is about 75 to 80 %.

After having mentioned a few technical details above I would suggest that you let your doctor decide on the need for the test if at all.

The main purpose of this article was to create awareness of certain less thought of physical problems which also exist. If used judiciously this can be of immense help to those who need it but, one must be cautious to not overreact or jump to conclusions at the drop of a hat.

Concluding finally I would like to say that food allergies are not as uncommon as they were thought to be, and they can cause symptoms which may vary from mild to very severe, and avoidance of allergens can give significant relief from those symptoms.

One must remember ‘Prevention is better than cure’.