The Problem with Broad Food Allergy Panels

A Word of Caution

Pediatricians please don’t give in to the temptation. Patients please do not give in to the temptation.

What Is the Problem with Large Food Allergy Panels?

First, food allergy tests and how to interpret them must be understood. What do food allergy tests mean?

Does it mean allergy severity? Nope.

Does a positive test mean allergy? Nope.

Does a negative test mean you don’t have a food allergy? Not necessarily.

Does it detect food sensitivities? Nope. On that note, does ANY test detect sensitivities? Nope. I don’t give a shit what Google or the marketers say. Pay attention to what real evidence says. Don’t be duped people.

Does it detect celiac disease? Nope

What Food Allergy Tests Actually Show

So what does it do? It tells us the likelihood of reacting to a food if exposed. That’s it. It will not predict severity of reaction. It certainly does not give severity of allergy.

Why Broad Panels Cause Problems

With this background, why not order broad panels?

There is a 50/50 chance if it is positive that it is a false positive. If you order a broad panel of food allergy tests and they are all positive but the predictive value in that setting is low, now what do you do? Usually, because the person ordering the tests didn’t understand the basics of what the tests mean so now they have to refer to someone who does know what they mean. That person will say the broad panel should NEVER had been ordered in the first place.

The Right Way to Order Food Allergy Tests

Targeted food allergy tests based off history is what needs to happen. The other aspect is food allergy tests need to be interpreted in the context of the patient’s history, but they also need to be interpreted in the context of other allergies such as pollen, shellfish, or latex allergy as there are significant cross-reactivity with these.

At times, depending on the history, other tests need to be ordered in conjunction with the food allergy tests to properly interpret them. Unless all the interactions are known, someone may not realize this.

The Takeaway

Moral of the story, if someone does not specialize in food allergies, they may not know what they don’t know. As a result, ineffective tests are often done. Foods may be unnecessarily be avoided.