IGHE and allergic disease: determined that the ratio of PR-specific IgE/SR-specific IgE is associated with a positive reaction to cooked PR, and the optimal cut-off is 0.47.9 However, among the patients with both SR and PR allergies in our study, two (50%) of four patient had a PR-specific IgE/SR-specific IgE ratio of <0.47; therefore, it might be difficult to determine whether a patient could eat PR safely by looking at only SR- and PR-specific IgE.