Three Questions An Allergist Uses To Diagnose Food Allergy

Dr. Alice Hoyt explains how allergists diagnose food allergies, differentiate them from other adverse reactions, and the importance of accurate diagnosis for effective treatment. This episode covers key questions to identify true food allergies and the significance of proper testing and treatment options.

Resources:

Find an Allergist Tool - American Academy of Allergy - https://acaai.org/resources/find-an-allergist/

Fast OIT - Food Allergy Support Team - https://fastoit.org/

keywords: food allergy, allergy diagnosis, anaphylaxis, F-Pies, immune response, allergy testing, treatment options, allergist, food reactions

Resources

📖 Navigating Food Allergies: A Parent’s Guide to Care, Coverage, and Confidence by Dr. Alice Hoyt - order from Amazon and more 

For Parents ➡️ Office Hours for Parents 

For Providers ➡️ Food Allergy Pediatric Hub

For Schools ➡️ Code Ana

For Potential Patients ➡️ Hoyt Institute of Food Allergy

🔎 Find an Allergist
AAAAI Allergist Finder
ACAAI Allergist Finder
OIT Allergist Finder

This podcast is the official podcast of the Hoyt Institute of Food Allergy. Information on, within, and associated with this site and Food Allergy and Your Kiddo is for educational purposes only and is not medical advice.

Transcript

Newsletter And New Book Preview

Question One Is Food The Trigger

Anaphylaxis Signs And Timing

FPIES Vomiting And Delayed Reactions

Why Positive Tests Mislead

SPEAKER_00 0:04

Hello, I'm Dr. Alice Hoyt, and welcome to Food Allergy and Your Kiddo. Today I'm going to talk about what really is a food allergy. What is an adverse reaction to a food? What is not an adverse reaction to a food? And how do allergists really sort out these different clinical presentations? If you don't already, subscribe to our newsletter, subscribe to Joyful Living at food allergy in your kiddo.com. And there you can actually reply to the newsletter and ask me your food allergy question. So today, what we're talking about is something that is in my book that comes out in April. I'm very excited about this book because as I mentioned in my last episode, I really tried to take everything that I have learned about food allergies over the course of my career and put it into this book for you, for parent of kiddo with food allergy. And so what we're talking about today is something I lay out in chapter one of the book, which is where I really try to discuss how we as allergists are thinking when you bring your kiddo in to see us for that first time. And you're wondering if your child has a food allergy. So let's dive into that. There are really three questions that we're thinking about to tease out what's going on with a kiddo when they present to our office with symptoms that could be a food allergy, where mom or dad is like, hey, this is what's happening with my kiddo. Is this a food allergy? I think they had an allergic reaction. And so the first question we're going to try to answer is whether or not a food is actually responsible for what's called the constellation of symptoms. Constellation of symptoms is a group of symptoms that are all happening together. When it comes to an anaphylactic reaction, that can be hives, swelling, trouble breathing, vomiting, coughing, sense of impending doom, meaning suddenly somebody really doesn't feel well, really wants to just, in case of little kiddos, they don't feel well. They really just want to be by their mom, be by their dad, or sometimes in the case of teenagers, they just they should really want to get home. Really want to get home. And adults too. And the sense of impending doom is a symptom that I really think is under-discussed, not undervalued, because we all value it, but it's just something that maybe we don't talk enough about and can absolutely be one of the reasons behind some of the decision making that occurs or why Epi is delayed sometimes. If you as an older person are thinking, I think I'm having an allergic reaction, should I give Epi? I think I should give Epi. I don't know if I should give Epi. And you're running all through this in your brain, and if you're having an allergic reaction, that can somewhat impede your good decision-making skills. And so when we're thinking about a constellation of symptoms, we're thinking about a group of symptoms that are occurring together. And in the case of a food allergy, like an anaphylactic food allergy, those symptoms that I mentioned, they're going to happen. At least one of them will happen after ingestion of the food. Other types of constellation of symptoms when it comes to a different type of food allergy, like F-PIs, food protein-induced entercolitis syndrome. So that is a type of food allergy. It is an adverse reaction to food. It is immune-mediated, right? But it is not an anaphylactic food allergy. So you're not necessarily, you're naturally not going to have hives. You, you, you or your little kiddo, it's much more common in babies than it is in adults, can have very, very profuse, very like scary vomiting. I say once you see F-Pies vomiting, you can't unsee it. Um, can have really bad diarrhea. And this happens within one to four hours, usually of ingesting the food. So it can be a little bit more delayed than what's happening in an anaphylactic food allergy. But that vomiting, that floppiness, that diarrhea that comes, that's called a constellation of symptoms. And so when somebody comes to see an allergist, wondering, okay, or thinking like, okay, my kiddo has a food allergy, that allergist, the first thing they're trying to figure out, the question they're trying to answer in their mind is the constellation of symptoms that's occurring in this little kiddo, is it because of a food? Is it being triggered by a food? Different example. A kiddo who comes in because they've been having hives for three weeks. And someone at some point, well-intentioned, ordered some allergy tests and now have a bunch of positive allergy tests to milk and to wheat and to peanut, but used to eat all these things and didn't have any problem and started avoiding them because of a positive test, but then is still having hives. Um, is that a food allergy? No, that's not a food allergy. The hives are happening, the symptoms are happening regardless of the food. So that first question, is food triggering a constellation of symptoms? No, food is not triggering the symptoms. Something's causing it, something's going on there, but it's not a food. So then it's not the diagnosis, it's not going to be an adverse reaction to a food. And so then if it's not an adverse reaction to a food, it's certainly not a food allergy. Right? So the first question we're wondering is, is food a trigger here? So what food is a trigger? What is the constellation of symptoms? It does seem to only really occur when the kiddo eats one particular food, maybe two foods, maybe three foods, right? We definitely have kids who have multiple food allergies. So then we're in the sort of the next step. And each of these three steps gets more and more complex, which is why it's so important to see a board certified allergist if you think your child has a food allergy. Because we as allergists are expertly trained to recognize food allergies, even nuanced ones, and provide diagnostics, therapeutics to help your child.

SPEAKER_01 6:46

Allergists go to med school, go to residency, go to fellowship.

SPEAKER_00 6:51

That is a bo and they take board exams, board exam in internal medicine and or pediatrics and allergy and immunology. So these are well studied, well-versed, specifically in allergy. That's who you want to see if you think your child has a food allergy. Okay, there's a tangent. There's a tangent. Hi Pam. Miss you.

Question Two Immune Or Not

SPEAKER_01 7:16

I texted with her yesterday. Anyway, so that first question is food the trigger? Let's move on to the next question. We're a little more in depth. Is the reaction, does it seem to be immune mediated?

Lactose Intolerance And Caffeine Reactions

SPEAKER_00 7:33

Well, what does that mean? Does it seem like the immune system is involved in this adverse reaction to a food? And this really is where clinical expertise is very important because you have to know of the different types of adverse reactions to a few to foods, immune-mediated and non-immune-mediated, to start to categorize your patient, to start to put them into their diagnostic bucket. Things like lactose intolerance, it's absolutely a real thing. It is an adverse reaction to a food. It is not immune-mediated. Lactose intolerance is when you have a deficiency in what's called lactase or an enzyme that breaks down milk sugar. If you don't have that enzyme, then milk sugar passes right on through into places in your digestive tract that it should not go. And then that causes your tummy to be upset, causes more water to come into the colon, which can cause bloating and diarrhea and crampiness, really nausea, just lots of discomfort. I never want to um play anyone who has these non-immune mediated adverse reactions to foods, because they can be incredibly uncomfortable, they can be difficult to tease out, they can be, they can significantly impact somebody's life. I mean, you know, if you're listening to this podcast, like you love a child who has a food allergy, you yourself might have a food allergy. At some point, you've you've you've wondered for yourself or for your child, like, what's going on with this child? And like, oh, this is, you know, the quality of life issues of, you know, just not being able to go to a restaurant with your friends and eat whatever you want. You're having to think about, is what I'm going to eat cause me, cause going to cause me any sort of fill in the blank. You know, of course we don't want life-threatening anaphylactic reactions. But honestly, who really wants any sort of like bloating diarrhea? Nobody wants that. Nobody wants to go out to dinner and have to deal with that, right? So I never like to downplay anybody's conditions because it all matters. Lactose intolerance, adverse reaction to a food, yes, immune-mediated, no. So that also caffeine, right? Lots of caffeine can make you feel very, very jittery. Is it an adverse reaction? Yes, it's an adverse reaction to the caffeine, or it's just a response to the caffeine. Because that is one thing that caffeine can do, but it is not immune-mediated. So let's get into what can be immune-mediated. Because if it's not immune-mediated, it's not a food allergy. And why is it important to know whether it's immune-mediated or not? Well, it's important to know what your diagnosis is. It's important to know if you have a food allergy. It's also important to know if you have a non-immune mediated adverse reaction to food. Don't get me wrong. It's important to know if you have a lactase deficiency so that you can take a lactase supplement and your symptoms be better. It's it's awesome. It's awesome, right?

SPEAKER_01 10:49

You cannot TX treat if you don't first DX diagnosed. So DX, TX.

SPEAKER_00 10:59

So then we get into question number three because the question number one was Is food the trigger to this constellation of symptoms?

SPEAKER_01 11:09

If it's not, then you need to entertain other diagnoses and other causes because it's not an adverse reaction to a food. Question number two, is this an adverse reaction to a food that is mediated by the immune system?

SPEAKER_00 11:29

Is the immune system playing a role here, right?

SPEAKER_01 11:33

Question number three, if yes, to number two, because if no, then we're dealing with non-immune mediated adverse reactions to foods, lactase, deficiency, etc. Question number three.

Treatments And Why Diagnosis Guides Care

FPIES Is Serious But Not IgE

SPEAKER_00 11:48

If it is immune-mediated, which was yes to question number two, then is it IgE mediated? And why does that matter? IgE matters because IgE is what permits anaphylaxis to occur. It's important to know whether or not you have a potentially anaphylactic food allergy so that you can carry epinephrine. Epinephrine, right now, comes in the form of an auto injector, it comes in the form of a nasal spray. Pretty soon it'll come in a form of little film that goes underneath your tongue. It's important to know your diagnosis so that you can treat it. And treatment for anaphylaxis is epinephrine. But also, if you have an IgE-mediated food allergy like a peanut allergy, like an egg allergy, then you can do oral immunotherapy, sublingual immunotherapy, you can use omolysimab or zolair. There are multiple peanut patches coming out, right? There's there are many ways to start to treat food allergies, anaphylactic or IgE-mediated food allergies. But you have to know what your diagnosis is before you can do that. And you have to know how to treat an emergency situation. So I mentioned earlier F pies, food protein-induced enterocolitis syndrome, where baby eats the food, they seem fine, and then maybe they wake up from their nap three hours later, vomiting, vomiting, vomiting, vomiting. Yes, it's an adverse reaction to a food. Yes, it's immune-mediated. We don't know a whole lot about F-PIs, especially not compared to IgE-mediated food allergies. Yes, F pies is immune-mediated, but it is not mast cell mediated. It is not going to be really helped by using an epinephrine, predosed epinephrine, auto injector, nasal epies. It's not indicated. Because in F pies, an F-PIs reaction is not an anaphylactic reaction. Does that mean it's not severe? No. F-PIs reactions can be crazy severe.

SPEAKER_01 13:57

Gotta know the DX before you can TX. Gotta know the diagnosis before you can really treat it and treat it really well, right?

Get Clarity With An Allergist

SPEAKER_00 14:07

So we talked about how to how to start to make a diagnosis of what really is a food allergy and what really is not a food allergy, so that you can have the appropriate treatment for you, for your child. We talked about those three questions that are in my book that I laid out in my book. Um, and why this is really important, and I probably should have led with this, but I mean, if you've made it this far in the episode, then you know why this is important. This is important so that you can be very clear on what diagnosis your child has and what they don't have. Which once you have clarity on a diagnosis, then you're also getting clarity on what foods are safe and what foods are not safe, what foods you need to avoid. You're also getting clarity on treatment options and able to stay up to date on treatment options because you have clarity on the diagnosis. So, all of that being said, I hope that you have found this episode helpful. I did an episode similar to this a few years ago, and it was actually one of the most downloaded episodes that we've had. I was kind of surprised because it was kind of dry. Like I think this episode is a little bit dry. I really enjoyed it and talk with people. Um, but some of this content I think is just really important, and I really want to share it. So, one of the reasons I think the the similar episode of Inside the Mind of an Allergist that we did a couple years ago has been so downloaded, is because I really did just sit there and talk to the microphone about the different types of adverse reactions to foods. And it is so nice just to have clarity on a diagnosis. And so if you're listening to this episode and you're really wanting more clarity on your child's diagnosis, then I want you to schedule a follow-up appointment with your allergist. Or maybe you haven't seen an allergist yet. So schedule an appointment with an allergist. You can ask your pediatrician for a referral. Um, in the show notes, I put a link to a find the allergist tool through the American Academy of Allergy, the American College of Allergy, also the Food Allergy Support Team. This is this big group of OIT allergists. Um, we have a find an allergist um tool on fastoit.org so that you can gain more clarity on your child's diagnosis. Because when you have more clarity on diagnosis, you have more clarity on treatment options. And it doesn't necessarily mean you you you're you want to pursue a treatment right now, but it certainly means that you want to be proactive in what is available for your kiddos so that you can be discerning about what should next steps look like, what would be great for your child. And if you're not up to date with the information, then you could be missing out. But if you're up to date with the information, because you have clarity in diagnosis, you have clarity and treatment options, then you you are on a good path, my friend. And I commend you. God bless you, God bless your family.

SPEAKER_02 17:34

Thanks so much for tuning in. Remember, I'm an allergist, but I'm not your allergist. So talk with your allergist about what you learned today. Like, subscribe, share this with your friends, and go to foodallergy in your kiddo.com where you can join our newsletter. God bless you and God bless your family.