Abstract
Background: Peanut allergy (PA) is usually diagnosed by a routine analysis, wherein the level of IgE antibody specific to whole peanut antigen (WPA-IgE) is measured. Recently, relatively new laboratory tests, namely, the basophil activation test (BAT) with WPA (WPA-BAT) and IgE antibody specific to a component protein Ara h2 (Ara h2-IgE), have been shown to be more sensitive than WPA-IgE for the diagnosis of PA. Objective: To compare the diagnostic accuracy of BAT with that of IgE antibody by using purified proteins Ara h1 and Ara h2 in Japanese children with PA. Methods: Twenty-four patients with PA (median age: 6 years) and 19 controls without PA (median age: 6 years) were enrolled in this study. PA was diagnosed by an oral food challenge test. BAT was performed with WPA, Ara h1 (Ara h1-BAT) and Ara h2 (Ara h2-BAT). The accuracy in the diagnosis of PA was estimated by receiver operating characteristic (ROC) curves. Results: Areas under ROC curves (AUC) were significantly high for Ara h2-BAT (0.967, p=0.023) and Ara h1-BAT (0.922, p=0.046). Although the AUC for WPA-BAT was also high (0.910), it was not significant (p=0.073). There were no significant differences in AUCs (p=0.561) between Ara h2-BAT and Ara h2-IgE (0.897, p=0.064). Conclusions: This study showed that Ara h2-BAT is as accurate as Ara h2-IgE for the diagnosis of PA in Japanese children.
