J Alle Clin Immun：新型检测花生过敏的方法

近日，来自墨尔本大学等处的研究人员发现了一种可以精确检测花生过敏的方法，这种新型的检测方法比一般传统的检测方法更为简便有效，而且可以最大限度的减少过度诊断给患者带来的伤害，目前，主要是用口部食物的检测方法（oral food challenge）来检测花生过敏症，这种方法受到一定程度的限制，而且耗时耗力，对患者可以带来明显的过敏性反应。

研究者的新型检测方法是用花生蛋白Arah2来进行两步的筛查，首先进行的是血液检测，其次用Arah2方法检测，这种方法的准确性比较高，这种新型的两步法比传统的口腔检测方法可以减小四倍的所用检测物。研究者Thanh Dang表示，这种方法有众多优势，不仅可以减少检测物的量，而且可以阻止不必要的检测风险，助理教授Katie Allen表示这种新型方法可以减少卫生系统的负担。

近年来，因为人类对很多食物敏感性的增加，导致众多的过敏性事件的发生，给食品检测以及过敏检测带来了很多困难，如今这种新型的方法可以帮助缓解目前这种问题，由于漫长的等待时间导致医生会面对很困难的任务，就是很困难来评估食品过敏性的阳性皮肤测试实验，这样有时候会判断错误。Allen博士表示，临床上对花生摄入有明显反应的症状即可直接认为是花生过敏症，但是很多时候，临床上表现并不明显或者小孩并没有暴露于食品之中，对于这种情况来说，诊断过敏就比较复杂和麻烦了。

研究者表示Arah2两步检测法可以被用于对食品过敏高风险的孩子们，比如湿疹和其它食物过敏等，或者是从来不吃花生的孩子和有食物过敏家族史的人。研究者相关的研究成果刊登在了国际杂志Journal of Allergy and Clinical Immunology上。

（生物谷：T.Shen编译）

doi:10.1016/j.jaci.2012.01.056
PMC:
PMID:

Increasing the accuracy of peanut allergy diagnosis by using Arah2

Thanh D. Dang, BBiomedSc (Hons)a, b, Mimi Tang, MBBS, PhD, FRACP, FRCPA, FAAAAIa, b, c, Sharon Choo, MBBS, FRACP, FRCPAc, e, Paul V. Licciardi, PhDa, b, Jennifer J. Koplin, PhDa, b, Pamela E. Martin, BBiomedSc (Hons)a, b, Tina Tan, BSca, b, Lyle C. Gurrin, PhDa, d, Anne-Louise Ponsonby, BMedSc, MBBS, PhD, FAFPHM, FRACPa, b, Dean Tey, MBBS, FRACPa, c, Marnie Robinson, MBBS, FRACPa, c, Shyamali C. Dharmage, MBBS, MSc, MD, PhDa, d, Katrina J. Allen, BMedSc, MBBS, FRACP, PhDa, b, c, , , HealthNuts study

Background Measurement of whole peanut-specific IgE (sIgE) is often used to confirm sensitization but does not reliably predict allergy. Ara h 2 is the dominant peanut allergen detected in 90% to 100% of patients with peanut allergy and could help improve diagnosis.

Objectives We sought to determine whether Ara h 2 testing might improve the accuracy of diagnosing peanut allergy and therefore circumvent the need for an oral food challenge (OFC). Methods Infants from the population-based HealthNuts study underwent skin prick tests to determine peanut sensitization and subsequently underwent a peanut OFC to confirm allergy status. In a stratified random sample of 200 infants (100 with peanut allergy and 100 with peanut tolerance), whole peanut sIgE and Ara h 2 sIgE levels were quantified by using fluorescence enzyme immunoassay.

Results By using the previously published 95% positive predictive value of 15 kUA/L for whole peanut sIgE, a corresponding specificity of 98% (95% CI, 93% to 100%) was found in this study cohort. At the equivalent specificity of 98%, the sensitivity of Ara h 2 sIgE is 60% (95% CI, 50% to 70%), correctly identifying 60% of subjects with true peanut allergy compared with only 26% correctly identified by using whole peanut sIgE. We report that when using a combined approach of plasma sIgE testing for whole peanut followed by Ara h 2 for the diagnosis of peanut allergy, the number of OFCs required is reduced by almost two thirds.

Conclusion Ara h 2 plasma sIgE test levels provide higher diagnostic accuracy than whole peanut plasma sIgE levels and could be considered a new diagnostic tool to distinguish peanut allergy from peanut tolerance, which might reduce the need for an OFC.