Involution of IgE sensitization to house dust mite allergen molecules by age

Background: The evolution of mite sensitization profiles from childhood to adulthood is associated with distinct clinical outcomes. Longitudinal sensitization trajectories have never been addressed across two generations over an extended time frame. Using molecular diagnosis, we aimed to investigate how the evolution of mite sensitization relates to the expression of rhinitis and asthma in adult versus pediatric patients over a 20-year period. Methods: Specific IgE (sIgE) to mite molecular allergens was determined using the MeDALL allergen chip (Der p 1, 2, 4, 5, 7, 10, 11, 14, 15, 37, 18, 21 and 23; Der f 1, Der f 2, Lep d 2, Blot t 5). Assessment was made in adult (n = 21), adolescent (n = 11), and pediatric patients (n = 19) with rhinitis and/or asthma, in T1 (20-years ago) and in T2 (current time). Results: After the 20-year period, the adult cohort significantly decreased the number of sIgE responses to mite components—T1: 7 [3–9] versus T2: 4 [2–6], median [IQR], p =.0040. A strong negative correlation was observed between age and the 20-year variation of sensitization count (r = −0.5305; p <.0001). In adults, the reduction in mite molecular IgE responses was associated with improvement in rhinitis (p =.0010) and asthma (p =.0020), reflecting disease progression patterns not observed in the pediatric cohort. Conclusions: This is the first analysis to show that molecular mite sensitization declines with aging, and this reduction may relate to decreased asthma and rhinitis symptoms and severity. This age-associated decline highlights the importance of careful clinical interpretation in older adults to avoid overtreatment and missed diagnoses.