Background: In atopic subjects with multiple sensitizations to inhalant allergens the relationship between the specific serum immunoglobulin (Ig) E and the in vivo response to each allergen is not well established.
Objective: To investigate the relationship between the specific serum IgE expressed as amount (kU/L) or density (specific IgE/total IgE percentage) with the in vivo response to inhaled allergens in rhinitic and asthmatic subjects with multiple sensitization.
Methods: By means of Reverse Enzyme AllergoSorbent Test (REAST) the absolute values and the density of specific IgE for each sensitizing allergen was determined. Rhinitics (n = 12) underwent nasal and asthmatics (n = 11) bronchial allergen challenges with the two to three sensitizing allergens for a total of 33 nasal and 32 bronchial challenges. Correlations and degree of concordance between specific serum IgE and results of challenges were calculated.
Results: IgE density significantly correlated with nasal challenge score (rs = 0.72, P < 0.001), bronchial challenge score (rs = 0.56, P < 0.001) and late asthmatic response (rp = 0.53, P < 0.005). Among subjects with three sensitizations, comparison of values of IgE density with the results of challenges showed significant concordance in graduation (chi2 = 11.3, P < 0.005).
Conclusions: In subjects with multiple sensitizations, the nasal and bronchial response to the different sensitizing allergens may be predicted, at least in part, by the IgE density. A satisfactory agreement between graduation of the IgE density to the different allergens and the in vivo response to the same allergens has been found within subject.