Study · Allergologia et immunopathologia · 2021

Egg yolk components in diagnosing egg allergy

What it found

In serum samples from 120 people, testing for specific IgE against egg yolk proteins Gal d 5 and Gal d 6 alongside egg white proteins improved the diagnosis of egg allergy.

The combination of Gal d 1 and Gal d 6 gave the best diagnostic accuracy.

What they found

Studies in people

Sensitization to multiple components

Among the egg-allergic group, 28.32% were sensitive to four of the six egg proteins, and 9.7% were sensitized to five of six components. Most patients were sensitized to more than one component rather than a single one.

Egg yolk sensitization

In the egg yolk allergy group, specific IgE levels were higher than in controls for Gal d 5 (average OD 0.541 vs. 0.226) and Gal d 6 (average OD 0.469 vs. 0.263).

Cross-reactions with Gal d 1

The cross-reaction frequency between the two egg yolk allergens and Gal d 1 was about 30%. The highest cross-reaction rates of Gal d 5 and Gal d 6 with Gal d 1 were 33% and 36%, respectively.

Best diagnostic combination

The combination of Gal d 1 and Gal d 6 had the largest area under the curve of 0.994, higher than Gal d 1 alone or other combinations. This suggests the best diagnostic accuracy for egg allergy.

Gal d 6 as major yolk allergen

The results showed that the major allergen of egg yolk was Gal d 6, not Gal d 5. Gal d 6 remains stable after cooking or heat treatment and resists digestion like Gal d 1.

What the authors conclude

“Our results suggested that there were individual differences in allergenicity of different egg allergen components, especially in the samples negative to egg allergy diagnosed but sensitive to egg yolk components.”
Lunhui H, Yanhong S, Shaoshen L, Huijing B, Yunde L, Huiqiang L, 2021

Also in their conclusions

  • They suggest that there are individual differences in allergenicity of different egg allergen components, especially in samples negative to egg allergy but sensitive to egg yolk components.
  • They indicate that component resolved diagnosis of egg yolk indispensably improves the value for egg allergy management.

How it was done

The authors say that egg yolk allergy has been gaining attention, but there was little information about egg yolk allergen components in egg allergy. They wanted to evaluate the diagnostic value of whole egg components, including egg white and egg yolk.

They collected serum from 99 people with egg allergy and 21 non-atopic controls. They used a modified ELISA to measure specific IgE against six egg proteins: Gal d 1, Gal d 2, Gal d 3, Gal d 4, Gal d 5 and Gal d 6. They then used ROC analysis to compare how well each component and combinations of components could diagnose egg allergy.

What it can’t tell you

  • This study used serum samples and did not perform skin prick tests or oral food challenges to confirm egg yolk allergy.
  • The results are from a single group of patients in Tianjin, China, so they may not apply to other populations.

The paper

Title
Component resolved diagnosis of egg yolk is an indispensable part of egg allergy
Type
Study
Evidence
Studies in people
Summarised from
Full text
Cite
Lunhui H, Yanhong S, Shaoshen L, Huijing B, Yunde L, Huiqiang L (2021). Component resolved diagnosis of egg yolk is an indispensable part of egg allergy. Allergologia et immunopathologia. doi:10.15586/aei.v49i2.31Free full textPubMed 33641288DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error