Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon, Korea.
Int Arch Allergy Immunol. 2012;157(2):147-50. doi: 10.1159/000327549. Epub 2011 Oct 5.
Wheat is an important food allergen associated with severe allergic reactions, including wheat-dependent exercise-induced anaphylaxis (WDEIA) and wheat-induced anaphylaxis (WIA). To diagnose WDEIA, an exercise challenge test following wheat ingestion is performed, which is time-consuming and unsafe. The compound ω-5 gliadin has been identified as a major allergen for WDEIA and WIA. We evaluated the diagnostic value of serum immunoglobulin E (IgE) ratios of ω-5 gliadin to wheat in adult patients with WDEIA or WIA.
In total, 27 patients were enrolled and classified into 2 groups according to the severity of their allergic reactions to wheat. Serum IgE, specific to wheat and ω-5 gliadin, was measured using the ImmunoCAP system. To evaluate the diagnostic value, receiver operator characteristic curves were produced.
Group 1 included 17 patients with a history of anaphylaxis and group 2 included 10 patients having urticaria or atopic dermatitis. Serum IgE specific to wheat was increased in 47% of group 1 and 100% of group 2. However, all patients in group 1 had high serum IgE specific to ω-5 gliadin, whereas only 20% of group 2 showed increased levels. To identify a better diagnostic value, the log-transformed IgE ratio of ω-5 gliadin to wheat was calculated, with the cutoff value at 0.3. Based on these criteria, we found 100% sensitivity and specificity.
This study confirms that the serum IgE ratio of ω-5 gliadin to wheat may be a useful marker for the diagnosis of WDEIA and WIA.
小麦是一种与严重过敏反应相关的重要食物过敏原，包括小麦依赖运动诱发的过敏反应（WDEIA）和小麦诱导的过敏反应（WIA）。为了诊断 WDEIA，需要在摄入小麦后进行运动挑战测试，这既耗时又不安全。复合 ω-5 麦醇溶蛋白已被确定为 WDEIA 和 WIA 的主要过敏原。我们评估了血清免疫球蛋白 E（IgE）对 ω-5 麦醇溶蛋白与小麦的比值在成年 WDEIA 或 WIA 患者中的诊断价值。
共纳入 27 例患者，根据其对小麦过敏反应的严重程度分为 2 组。采用 ImmunoCAP 系统检测血清 IgE 对小麦和 ω-5 麦醇溶蛋白的特异性。为评估诊断价值，生成了受试者工作特征曲线。
第 1 组包括 17 例有过敏反应史的患者，第 2 组包括 10 例有荨麻疹或特应性皮炎的患者。第 1 组 47%的患者血清 IgE 对小麦特异性升高，第 2 组 100%的患者血清 IgE 对小麦特异性升高。然而，第 1 组所有患者的血清 IgE 对 ω-5 麦醇溶蛋白均升高，而第 2 组仅 20%的患者升高。为了确定更好的诊断价值，计算了 ω-5 麦醇溶蛋白与小麦的 IgE 比值的对数转换值，以 0.3 为截断值。根据这些标准，我们发现敏感性和特异性均为 100%。
本研究证实，血清 ω-5 麦醇溶蛋白与小麦的 IgE 比值可能是诊断 WDEIA 和 WIA 的有用标志物。
