Published: September 2025
Medically reviewed by:
Gary Falcetano, PA-C, AE-C
Food allergies are a significant concern for both patients and healthcare providers, often presenting challenges that require precise diagnosis and management strategies. Egg allergy, in particular, is one of the most common food allergies, especially among children and can lead to severe reactions.
In this illustrative case study, we delve into the journey of Thomas, a 17-year-old boy who has lived with a persistent egg allergy. Despite the seriousness of his condition, Thomas faces ongoing challenges in managing his allergy, including recent emergency room visits and a lack of adherence to carrying his epinephrine autoinjector. This case study highlights the importance of thorough diagnostic testing and patient education in reinforcing the risks associated with egg allergies and ensuring effective management.
Read on to explore Thomas's story and the critical steps his healthcare provider took to evaluate and enforce the seriousness of his allergy, utilizing specific IgE blood testing to guide better health outcomes.
Patient History
Thomas, a 17-year-old boy with a history of egg allergy, visits his healthcare provider following two recent emergency room visits due to a reaction to egg. Thomas has stopped carrying his epinephrine autoinjector, and his mother is worried that he doesn’t take his allergy seriously.
Thomas’ healthcare provider conducts a full clinical history and physical examination and decides to test him for sensitization to egg white and components to help reinforce the seriousness of his egg allergy diagnosis.
Thomas’ personal history
- Thomas was rushed to the emergency room at age 2 when he experienced difficulty breathing, an itchy mouth and swollen lips after eating egg.
- A presumptive diagnosis of egg allergy was made, but no testing was done.
- At the age of 7, Thomas was diagnosed with moderate persistent asthma associated with allergic sensitizations to house dust mites and grass pollen.
Did you know?
Egg allergy, in particular, is one of the most common food allergies, especially among children and can lead to severe reactions.
Thomas’ ImmunoCAP™ test results
These results together with this patient's case history and symptoms, help confirm the diagnosis.
ImmunoCAP™ specific IgE test results (kUA/l) |
||
Test* |
Type |
Thomas' results |
Egg white |
Whole allergen |
56.9 kUA/I |
Gal d 1 (Ovomucoid) |
Allergen component |
10.73 kUA/I |
Gal d 2 (Ovalbumin) |
Allergen component |
9.74 kUA/I |
Product names: ImmunoCAP Allergen f1, Egg white, ImmunoCAP Allergen f233, Allergen component nGal d 1 Ovomucoid, Egg and ImmunoCAP Allergen f232, Allergen component nGal d 2 Ovalbumin, Egg
Egg component features
- Ovomucoid is resistant to heat denaturation and is a marker of persistent egg allergy.1
- Ovalbumin, conalbumin and Lysozyme are susceptible to heat denaturation.1
- Lysozyme, a glycosidase, has been reported to be extensively utilized by the food (cheese, wine, etc.) and pharmaceutical (like eye drops) industries as a preservative due to its antibacterial properties.2-3
Differential diagnosis
Thomas’ test results revealed that he was highly sensitized to ovomucoid, which is associated with an increased risk of systemic reaction to all forms of egg.1
Refined diagnosis
- Sensitized to egg whites
- Sensitized to ovalbumin and ovomucoid proteins
- Risk of reaction not reduced by extensively baking the egg
Healthcare provider management plan
- Thomas was advised that his sensitization to ovomucoid means he will likely react to egg in all forms.
- Thomas' healthcare provider reinforced the importance of Thomas avoiding accidental or purposeful ingestion of eggs and products containing eggs.
- Thomas' healthcare provider advised him to always carry his emergency adrenaline autoinjector.
Follow-up
- Thomas has had no further episodes and is fit and well. His healthcare provider checks his autoinjector technique and is satisfied.
Conclusion
Thomas's case highlights the importance of accurate diagnosis and vigilant management of egg allergies. It shows how advanced diagnostics help enable primary care providers to make informed decisions, enhancing patient safety and quality of life. ImmunoCAP Specific IgE tests can help identify allergen sensitization accurately, reduce unnecessary restrictions and guide personalized care.
The people, places and events depicted in these case studies and photographs do not represent actual patients, nor are they affiliated with Thermo Fisher Scientific.
Find out more about ImmunoCAP Specific IgE tests in food allergy.
