Wang Julie, Godbold James H, Sampson Hugh A
Department of Pediatrics, Division of Allergy and Immunology, Mount Sinai School of Medicine, New York, NY 10029-6574, USA.
J Allergy Clin Immunol. 2008 May;121(5):1219-24. doi: 10.1016/j.jaci.2007.12.1150. Epub 2008 Feb 19.
In vitro testing is commonly used to diagnose and manage allergies. Clinical reactivity has been correlated with food-specific IgE levels by using the ImmunoCAP (Phadia, Uppsala, Sweden).
To determine whether IgE levels derived from different assays are equivalent to those measured by ImmunoCAP.
Fifty patients from the Mount Sinai Pediatric Allergy practice were prospectively enrolled. For each deidentified sample, specific IgE levels were measured to egg, milk, peanut, cat, birch, and Dermatophagoides farinae at different laboratories, each using a different assay system (Phadia ImmunoCAP, Agilent Turbo-MP, and Siemens Immulite 2000). Results were analyzed to determine whether IgE measurements were equivalent. Food allergen-specific IgE levels were correlated with clinical data and around empirically determined thresholds that predict probability of clinical disease in 50% or 95% of subjects.
Variable degrees of agreement existed among the 3 assays. Immulite 2000 overestimated all specific IgE levels compared with ImmunoCAP. Turbo-MP overestimated for egg but underestimated for birch and D farinae. Differences for milk, peanut, and cat were observed, without a trend toward overestimation or underestimation. Furthermore, several values for the food allergens were discrepant around the 50% and 95% positive predictive values for clinical reactivity.
Discrepancies in specific IgE values from 3 different assays can potentially lead to altered management and treatment. The predictive values for clinical reactivity associated with food-specific IgE levels determined by ImmunoCAP should not be applied to results from other assays.
体外检测常用于诊断和管理过敏症。通过使用免疫捕获法（瑞典乌普萨拉法迪亚公司），已将临床反应性与食物特异性IgE水平相关联。
确定不同检测方法得出的IgE水平是否等同于免疫捕获法测量的水平。
前瞻性纳入了50名来自西奈山儿科过敏诊所的患者。对于每个去识别化的样本，在不同实验室对鸡蛋、牛奶、花生、猫、桦树和粉尘螨的特异性IgE水平进行测量，每个实验室使用不同的检测系统（法迪亚免疫捕获法、安捷伦Turbo-MP和西门子Immulite 2000）。对结果进行分析以确定IgE测量值是否等同。食物过敏原特异性IgE水平与临床数据相关，并围绕经验确定的阈值，这些阈值可预测50%或95%受试者出现临床疾病的概率。
三种检测方法之间存在不同程度的一致性。与免疫捕获法相比，Immulite 2000高估了所有特异性IgE水平。Turbo-MP对鸡蛋IgE水平高估，但对桦树和粉尘螨IgE水平低估。观察到牛奶、花生和猫的IgE水平存在差异，无高估或低估的趋势。此外，在临床反应性的50%和95%阳性预测值附近，几种食物过敏原的值存在差异。
三种不同检测方法得出的特异性IgE值的差异可能会导致管理和治疗的改变。免疫捕获法确定的与食物特异性IgE水平相关的临床反应性预测值不应应用于其他检测方法的结果。
