Not Every Food Allergy is Anaphylactic
Is it Anaphylactic?
Like all clubs, food allergy parents have their own lingo.
Check out any FA parent message board on any day and someone will have posted a message like “My son is kiwi, anaphylactic PN, egg. Anyone else eat this waffle?”
Because new parents are also joining these groups every day, within minutes someone asks - “How do you know if an allergy is anaphylactic?”
The prevailing wisdom is “any food allergy can result in anaphylaxis. A previous reaction does not predict a future reaction.”
But this is not technically correct. It depends on what you mean when you say “allergy.” Not all allergies are the same. They are all serious, but some can have deadly consequences while others don’t.
The different kinds of allergy should be explained to every parent whose child is diagnosed with a food allergy. It is critical information that guides how a parent might identify a future allergy, how they will navigate life with the one that’s been identified, what odds their child has of outgrowing the allergy, and what potential treatments are.
The Three Types of Food Allergies
There are three types of food allergies. I’m going to call them Potentially deadly allergies, Childhood Stomach allergies, and Chronic Issue allergies. (Their real name are IgE-mediated, Non-IgE-mediated, and mixed, respectively.) The three types of food allergies have overlaps and can be hard to tell apart but knowing the difference will give you clarity on what to do next.
Summary of Three Types of Food Allergy
Potentially deadly, or IgE-mediated, allergies are the “anaphylaxis” allergies that parents are terrified of. Potentially deadly allergies can develop at any age, but most develop in early childhood when the immune system is learning.
Reaction symptoms come on fast, usually within seconds or minutes of eating a food. Almost all the reactions happen within 4 hours, though it is possible for them to be delayed. The symptoms of potentially deadly allergies are sudden hives, redness of the skin, stomach cramping & pain, vomiting, diarrhea, coughing, sneezing, closing of the airways, and fever.
Any of the symptoms above are possible but many reactions may only involve the skin or the stomach!
These allergies are “IgE mediated” because the symptoms are set-off by IgE antibodies. Potentially deadly allergies are diagnosed by skin-prick, or blood testing because those tests measure IgE antibodies.
IgE antibodies are part of your immune system’s tool kit for fighting parasites like worms. The symptoms look like the body violently trying to eject or kill a parasite, because that’s what it’s doing. The reactions can stop as fast as they started if the body decides the parasite is gone. And the reaction happens in so many places because IgE antibodies float around everywhere in your blood.
Childhood stomach allergies, or non-IgE mediated, allergies are most commonly diagnosed in small babies. Symptoms are usually limited to the stomach and intestines, though some herpes-like eczema also happens. That’s why I call them childhood stomach allergies.
You may have heard this group of allergies called FPIES (food-protein induced enterocolitis syndrome), enteropathy, proctitis, or proctocolitis. Different antibodies, including IgA and IgM, which are found in the mucus lining of the GI system react to food proteins. Enterocolitis can happen anywhere in the gut, enteropathy in the small bowel, proctitis in the rectum, and proctocolitis in the colon.
Symptoms from childhood stomach allergies are usually delayed 4 or more hours after a food is eaten, perhaps because that’s how long the food can take to make its way to the reacting part of the GI system.
Because childhood stomach allergies are reactions happening in the stomach lining, you don’t tend to get the breathing issues or hives. Instead, what you see is diarrhea, watery stools, or maybe blood or mucus in stools, along with belly pain. The skin is sometimes involved with herpes like raised patches. The symptoms from these allergies can take days or weeks to go away even after the food is removed.
This is because childhood stomach allergies are harder for parents to spot, and these allergies will not show up on IgE testing. By the time they are diagnosed, the baby may have been eating that food every day for weeks or months.
Technically, you can have a childhood stomach allergy to any food, but they seem to be most common to milk, wheat, rice, oat, and other grains.
Chronic Issue allergies, or mixed IgE & non-IgE allergies, are things like chronic eczema and Eosinophilic Esophagitis (EoE). As the medical name suggests, the symptoms are triggered by a combination of IgE cells and other immune cells, like eosinophils.
Although there is still debate on this matter, a large and growing group of doctors agree that some eczema can be triggered by an underlying food allergy. The symptoms are limited to the skin which develops eczema patches that do not heal up with steroids. EoE is limited to esophagus issues like pain when swallowing and projectile vomiting like the food can’t even make it into the stomach.
Because there are IgE cells involved in these allergies, skin-prick or blood testing will show IgE antibodies. But a lot of people have IgE antibodies with no symptoms and no allergy, so from there doctors look to an elimination diet. You have one of these conditions if that food is removed and the eczema or EoE heals, and if the food is re-introduced, the eczema or EoE flares again.
Be Careful with Language
From speaking to parents, it seems that allergists are not being careful with their language. Most of our thinking to date on diseases is about treatment, not prevention. So explaining the root cause of the disease can feel irrelevant as long as you make the symptoms go away.
But with a disease that seems to strike at random, parents desperately want to know what is happening so that they can understand why it’s happening, and ideally stop it from getting worse.
Any time a question comes up again and again, it’s a red flag that there is a piece of information that is not getting through.
Let me know in the comments if this helped. If you feel anything in this post is inaccurate, please let me know. I’m trying to stop misinformation, not spread it.
