Late tolerance to hen’s egg can be amarker of subsequent aeroallergensensitisation

Resumen

Background:Hen’s egg is basic in mosthuman nutritional options, and it is con-sidered an excellent low cost source ofproteins, what makes it one of the mostfrequent causes of food allergy around theworld. In Spain it causes 44% of allergyevaluations related to food allergy in children under five, with a total prevalence ofallergy between 0.5 and 2.7%. A positiveIgE for egg proteins during the first years oflife is considered a strong risk factor in thedevelopment of atopic diseases. Severalstudies show that a specific IgE immuneresponse to egg proteins is the main andearlier risk marker of late sensitisation toaeroallergens and respiratory allergic dis-eases.Methods:We have evaluated 66 childrenunder fourteen years old with provenhypersensitivity to egg proteins, and withouttolerance at the moment of inclusion. Thepatients were followed from 3 to 10 yearsafter the first visit, and were divided in twogroups, those who did not tolerate hen’s egg36 months after diagnosis (n534), andthose who tolerated it in less than 36 monthsafter diagnosis (n532). A pre-establishedstandardized protocol with special focus onparent’s allergic diseases and pregnancyevents (collected from clinical histories andpersonal interview by phone) was applied, aswell as skin prick tests and IgE determina-tions. The results were processed andanalysed using SPSS 12.0 statistical pack-age.Results:The mean age of tolerance to eggproteins was 3.3172.32 years for globalsample. We found that those patients thatdid not tolerated hen’s egg three years afterthe diagnosis had a subsequent increase inhouse dust mite (P50.040) and animaldander (P50.006) sensitisation, when com-pared with patients that tolerated egg by 36months after the diagnostic. We did not findany differences in food sensitisations.Conclusions:More than three years withoutdeveloping egg tolerance from diagnosiscould be a predictive factor of atopic diseaserisk and can be a marker of later sensitisa-tion to aeroallergens like house dust miteand animal dander