The doctor has suggested that your child be tested for food allergies. There’s some reason to suspect some of the symptoms experienced recently have been triggered by something he ate. You’ve now got a referral in hand for a board-certified allergist and directions to request an evaluation for food allergies. What should you expect?
Yes, You Need the Allergist
Your pediatrician is amazing. She’s deftly guided your family through the first weeks of life and helped you manage health and wellness for your child into the years that followed. You trust her. And yes, she could order the testing herself. A board certified allergist, however, is specifically trained in this area, and is likely more updated on current research pertaining to food allergies. She can help your family navigate the specific hurdles that come with food allergy testing and management.
Targeted Not Panel Testing
In 2016, a team of allergy experts conducted an extensive review of the food allergy tests ordered by different types of healthcare providers in a given year. Their findings indicate that general practitioners were more likely to order broader panels for testing that resulted in not just higher costs to patients and payors, but also often led to patients unnecessarily removing foods from their diets. Reuters Health spoke with one of the study’s authors, Dr. Dave Stukus, regarding the study and wrote that broad panel tests, “can lead to overdiagnosis, with potentially harmful effects, including stunted growth due to unnecessary dietary restrictions.”
In comparison, allergists tend to order specific, targeted testing after a full health evaluation. They are less likely to order broad panels. Your allergist will use testing as part of a broader diagnostic process that includes your child’s health history and will likely limit the number of foods tested for at one time and focus specifically on those that there seems to be reason to suspect.
Not a Screening Test
Let’s break this down a little more for clarity. Food allergy tests – both skin tests, known as SPT, and blood tests – have a high rate of false positives. That’s not to say the tests are useless. They can be a valuable tool in confirming a suspected allergy and in helping your allergist monitor your child’s allergies as they grow. It is, however, why broad panels – tests that measure a wide range of foods, many of which are rare food allergens – can lead to overdiagnosis when used on their own and interpreted by someone that does not have depth of experience with food allergies.
A board-certified allergist has been trained to properly order tests and read the results. After discussing your child’s health history and identifying likely allergic triggers based on a full health evaluation, the targeted testing your allergist conducts will help confirm a suspected allergy. This article in Kids with Food Allergies does a good job at explaining it if you want to dig deeper.
Your allergist will identify the right test for your child. It may be a skin test that can be done in the doctor’s office and yield results in as little as 15 minutes. The test will be performed on the child’s arm or back. A small sterile probe that contains a bit of the food allergen being tested will be used to prick the skin. The patient must sit and not itch or touch the test area until the results can be read. If a test spot develops a wheal (which resembles an insect bite), it's considered positive. The test will also include a positive and negative control to help the doctor properly assess the test.
Your allergist may also order a blood test. You’ll receive an order for specific allergens to be tested that you’ll take to a lab. They’ll draw the necessary vials of blood and process the test. The results can take longer to return as a result. The test is measuring the level of IgE antibodies present in the blood for specific potential allergens.
If your allergists confirms your child has food allergies, she’ll provide you with an allergy management plan that will help your child avoid food allergen triggers and properly respond in the event of a reaction. If your doctor gives you a prescription for an auto-injector of epinephrine, fill it. One of the biggest factors in whether or not a food allergic individual survives a life-threatening reaction is whether or not epinephrine was administered in a timely fashion.