EVALUATION OF THE OVERALL DEGREE OF SENSITIZATION TO AIRBORNE ALLERGENS BY A SINGLE SEROLOGIC TEST - IMPLICATIONS FOR EPIDEMIOLOGIC STUDIESOF ALLERGY

In most epidemiologic studies of respiratory allery, the overall degre e of sensitization is usually measured by indices based on skin prick test reactions to a panel of relevant airborne allergens. In the prese nt study we used a single assay (CAP-Phadiatop, Pharmacia, Uppsala, Sw eden), which is based on the reaction between serum-specific IgE and a mixture of locally relevant inhalant allergens to measure the degree of sensitization to inhalants in the sera of 1815 young Italian men, i n whom a complete diagnostic workup for respiratory allergy was perfor med in parallel. The intensity of reaction in the CAP-Phadiatop assay was highly correlated with: (1) an allergy index (p < 0.005), based on skin prick test reactivity to seven relevant inhalant allergens (Derm atophagoides pteronyssinus, mixed grass pollens, cat epithelium, Parie taria judaica, Olea europaea, Artemisia vulgaris, Alternaria tenuis); (2) the concentration of specific IgE to the same allergens, measured by CRP-RAST(p < 0.001), in both monosensitized and polysensitized subj ects; (3) the rate of respiratory allergic diseases (p < 0.0001). Ther efore CAP-Phadiatop intensity of reaction is a reliable indicator of t he overall degree of sensitization to inhalant allergens. Furthermore, as demonstrated by relative operating characteristic analysis, it has an acceptable detectability power in identifying subjects with sympto matic expression of the atopy status [P(A) = 0.948]. The evaluation of the degree of sensitization to inhalants by a single and semiautomate d assay represents a step forward in the standardization of procedures for epidemiologic studies of inhalant allergic diseases and for mass screening programs, which are aimed at identifying predictive markers of disease susceptibility.