Exploring Cross-Reactivity Among Hen, Duck, and Quail Eggs in Children with Hen’s Egg Allergy

OBJECTIVE: To investigate cross-reactivity among hen, duck, and quail eggs in children with suspected egg allergy.METHODS: A cross-sectional study enrolled 20 children with a history consistent with egg allergy. Specific immunoglobulin E levels to hen’s egg white and egg yolk, skin prick test (SPT) to fresh raw hen, duck, and quail eggs, and oral food challenges in selected cases were performed for egg allergy evaluation. Thirty children with a clear history of egg tolerance were recruited as a control group. SPT were performed according to standardized protocols by trained personnel. Mean wheal diameter from SPT measured cross-reactivity and Spearman’s correlation examined the cross-reactivity pattern.RESULTS: The median age of participants with suspected egg allergy was 1.1 years and 3.6 years for the control group. Reported allergic reactions when entering the study were primarily to hen eggs, mainly urticaria/angioedema (70%). Anaphylaxis occurred in 20%. Participants with suspected hen’s egg allergy were sensitized to at least one of the avian eggs, while controls showed a negative response. Among these participants, SPT positivity rate for quail eggs was high (60% for whites and 55% for yolks), followed by duck eggs (50% for whites and 30% for yolks). Moderate correlations were found between egg whites and egg yolks within each egg type. A negative correlation was found between henegg whites and duck egg yolks (r = -0.127), and hen and duck eggs showed a weak correlation (r = 0.169–0.259). Patients with multiple egg sensitizations had a higher prevalence of earlier age of first reaction (p = 0.049) and a maternal history of atopy (p = 0.03).CONCLUSION: This study suggests lower sensitization rates to duck eggs. Evaluating duck egg reactivity could benefit children with suspected hen’s egg allergy.