Ep. 97: The Nuances of Food Allergy Testing
Part of the series: Allergy, Asthma & Immunology Innovations Podcast
This podcast was made in partnership with Allergy & Asthma Network.
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LISTEN TO EPISODE 97:
Think diagnosing food allergies is as simple as running a test? Think again. Food allergy testing is a maze of gray areas, false positives, and, hopefully, a clear food allergy diagnosis.
Navigating food allergy testing can feel overwhelming, with skin pricks, blood tests, and conflicting advice. How do you determine which tests are truly useful? How can you avoid unnecessary dietary restrictions from false results?
In this episode, Dr. David Stukus, a board-certified allergist and immunologist, joins Dr. Gupta and Kortney to demystify the science of food allergy testing. From the importance of patient history to the latest diagnostic tools, Dr. Stukus provides clear guidance to help you make informed decisions while navigating food allergy testing.
What We Cover in Our Episode About Food Allergy Testing:
The Crucial Role of History in Food Allergy Diagnosis: Dr. Stukus highlights why understanding a patient’s reaction history (symptoms, timing, and context) is critical for guiding effective testing decisions.
Choosing the Right Tests: We break down skin prick testing, blood tests like IgE and component testing, and innovations like epitope mapping. Dr. Stukus explains why IgG testing is untrustworthy and emphasizes oral food challenges as the gold standard for diagnosis.
False Positives and Negatives: Learn why expert interpretation of test results is crucial and how overtesting can lead to unnecessary restrictions and confusion.
When to See an Allergist: Practical advice on when to consult a specialist and what to expect during your visit for evidence-based care.
About Our Guest
Dr. David R. Stukus is a renowned allergist and immunologist at Nationwide Children’s Hospital and a professor at The Ohio State University College of Medicine. Known for his dedication to patient education and myth-busting in allergy care, Dr. Stukus is a trusted expert in food allergies, asthma, and environmental allergies.
Follow Dr. Stukus on Instagram: @allergykidsdoc
More resources about allergies:
More episodes about allergic reactions:
Types of Food Allergy Testing
Skin Prick Testing
A small amount of allergen is placed on the skin, and the area is pricked to allow the substance to enter the skin. If you’re allergic, a raised bump similar to a mosquito bite will appear within 15-20 minutes. You must not be taking antihistamines for 3 days before the test.
Blood Testing
IgE Testing: This test measures specific IgE antibodies in the blood that are produced in response to allergens. It’s useful for patients who cannot undergo skin testing, though results can sometimes include false positives.
Component Testing: A more advanced form of IgE testing, this method identifies specific proteins within a food that trigger allergic reactions, providing more detailed information than standard blood tests.
Component Testing: A more advanced form of IgE testing, this method identifies specific proteins within a food that trigger allergic reactions, providing more detailed information than standard blood tests.
IgG Testing: Often marketed as a food sensitivity test, IgG testing is not recommended for diagnosing food allergies. It measures past exposure to foods rather than immune system overreactions and can lead to unnecessary dietary restrictions.
Epitope Mapping: This emerging test identifies specific parts of an allergenic protein that interact with the immune system. It provides a highly detailed analysis, helping to refine diagnoses and guide treatment plans.
Oral Food Challenge
Known as the gold standard, this test involves consuming increasing amounts of a potential allergen under medical supervision to observe for reactions. It is highly accurate but requires careful monitoring by a specialist.
Timestamps
Our episode explores the tests available to diagnose a food allergy
00:54 Introduction to Dr. Stukus
01:32 The importance of a detailed reaction history in diagnosis
02:34 Determining which foods require testing
04:05 Initial allergy testing during the first visit to an allergist
05:44 How allergists decide which testing methods to use
07:01 Overview of skin prick testing for allergies
11:30 Blood testing for food allergies and its role in diagnosis
14:01 Risks of patients interpreting test results on their own
14:41 Explanation of false positives and false negatives in allergy testing
14:49 The problems with IgG testing for food allergies
18:22 Why testing for all possible allergens is not recommended
20:21 Component testing for more precise allergy diagnosis
25:38 Epitope mapping as an advanced diagnostic tool
30:11 Factors that influence the severity of an allergic reaction
32:14 Explanation of the oral food challenge process
35:34 Double-blind oral food challenge and its significance
38:34 Guidance on when to consult an allergist
