[Rapid specific IgE assay (ImmunoCAP® RAPID) and skin prick test in the diagnosis of allergic disease].

Background: ImmunoCAP® Rapid is a rapid test kit to measure the allergen-specific IgE to the eight major inhalation allergen (cat, mite, orchard grass, ragweed, wormwood, dog, cockroach, Japan cedar).

Methods: We performed ImmunoCAP® Rapid 83 patients with allergic disease (26 males, 57 females, median aged 43 years, 53 of asthma, 43 of allergic rhinitis) in our allergy center. ImmunoCAP® Rapid results were compared with those of skin prick test (SPT).

Results: Although total positive allergens of SPT were higher than that of ImmunoCAP® Rapid (26.5% vs 22.5%, p<0.05), there was no significantly difference of each positive allergen between two tests. The rate of ImmunoCAP® Rapid to Japan cedar was almost equivalent to SPT in all patients (68.7% vs 55.4%, p=0.07). In contrast, the rate of ImmunoCAP® Rapid to Japan cedar was higher than SPT in patients with rhinitis (90.4% vs 71.4%, p<0.05). Efficiency between ImmunoCAP® Rapid and SPT was 86.4%, sensitivity was 66.9%, and specificity was 93.4%. The reactivity of ImmunoCAP® Rapid to allergens significantly correlated with sizes of SPT (erythema: r=0.645, urticaria: r=0.657).

Conclusion: Although identification rate in the screening ImmunoCAP® Rapid slightly inferior to SPT, this test system was useful for diagnosis of Japan cedar and mite.