The prevalence of food allergy has doubled over the last decade. An allergy occurs when something causes your body’s immune system to overreact to a substance. Reactions to foods can cause a variety of symptoms that can be as mild as an itchy rash or hives to a more serious reaction including anaphylaxis that can develop rapidly and be deadly. Food reactions are the result of the immune system producing an antibody, Immunoglobulin E (IgE) to certain foods or the result of a non-IgE, cell mediated reaction, which usually presents hours after eating a certain food. Some examples of non-IgE mediated reactions include eosinophilic esophagitis, celiac disease, and food protein induced enterocolitis (FPIES).
The most common food allergens are:
- Tree nuts
- Peanut
- Shellfish
- Fish
- Egg
- Milk
- Soy
- Wheat
Oral Allergy Syndrome is a common adverse reaction to food in which the fresh allergen in certain fruits and vegetables appears very similar to pollen and can elicit symptoms of itching and swelling around the mouth and a scratchy feeling in the back of the throat. Individuals often develop oral itch after eating apple, peaches, pears, melons, cantaloupe, banana, and avocado. Cooked forms of the food are generally well tolerated.
Eosinophilic Esophagitis can be related to a food reaction that often occurs hours to days after eating foods and can lead to reflux symptoms, abdominal pain, nausea, vomiting and trouble swallowing certain foods particularly meats such as turkey and chicken.
How to Test for Food Allergies:
A Board Certified Allergist will perform a thorough history and appropriate skin testing and combine the results of both to give you a proper diagnosis. This testing can be done at your initial visit. Although blood testing can also be performed, skin testing is more accurate. Oral allergy syndrome can be diagnosed by testing for the pollen allergy and testing with fresh fruits or vegetables in question.
What is the risk that the sibling of my peanut allergic child will also develop peanut allergy?
The risk of peanut allergy in the general population is approximately 1% . Multiple studies have shown that the risk in non-monozygotic twin siblings is around 6-8% and as high as 65% in monozygotic twins. We recommend that siblings born into a family with a peanut allergic child be assessed by a Board Certified Allergist to determine whether they need an in office food challenge or skin testing prior to introduction.