Detection of IgE Reactivity to a Handful of Allergen Molecules in Early Childhood Predicts Respiratory Allergy in Adolescence

Sensitization in early childhood may precede respiratory allergy in adolescence. IgE reactivity against 132 allergen molecules was evaluated using the MeDALL microarray in sera obtained from a random sample of 786 children at the age of 4, 8 and 16years in a population based birth cohort (BAMSE). Symptoms were analyzed by questionnaire at ages 4, 8 and 16years. Clinically and independent relevant allergen molecules accounting for ≥90% of IgE reactivities in sensitized individuals and at all time-points were identified as risk molecules and used to predict respiratory allergy. The data was replicated in the Manchester Asthma and Allergy Study (MAAS) birth cohort by studying IgE reactivity with the use of a commercial IgE microarray. Sera were obtained from children at the ages of 3, 5, 8 and 11years (N=248) and the outcome was studied at 11years. In the BAMSE cohort 4 risk molecules could be identified, i.e.: Ara h 1 (peanut), Bet v 1 (birch), Fel d 1 (cat), Phl p 1 (grass). For MAAS the corresponding number of molecules was 5: Der p 1 (dust mite), Der f 2 (dust mite), Phl p 1 (grass), Phl p 5 (grass), Fel d 1 (cat). In BAMSE, early IgE reactivity to ≥3 of 4 allergen molecules at four years predicted incident and persistent asthma and/or rhinitis at 16years (87% and 95%, respectively). The corresponding proportions in the MAAS cohort at 16years were 100% and 100%, respectively, for IgE reactivity to ≥3 of 5 risk molecules. IgE reactivity to a few allergen molecules early in life identifies children with a high risk of asthma and/or rhinitis at 16years. These findings will be of importance for developing preventive strategies for asthma and rhinitis in children. •IgE reactivity to only few allergen molecules in early childhood predicts respiratory allergy in adolescence•It may be possible to develop individualized risk prediction charts for allergic respiratory diseases.•These findings could be targets for novel intervention therapies. Birth cohorts are essential for understanding the life course of allergy. With a novel approach using a large panel of micro-arrayed allergen molecules from more than forty allergen sources, we identified a strong IgE signature against a handful of allergen molecules at ages 3–5years that predicted respiratory allergy with >90% probability up until adolescence in two geographically separate populations. The results suggest generalizability across populations. The findings are of clinical importance for pediatricians or physici