Department of Emergency Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232-4700, USA.
Am J Emerg Med. 2012 Nov;30(9):1955-61. doi: 10.1016/j.ajem.2012.04.018. Epub 2012 Jul 15.
The objective of this study is to evaluate the diagnostic performance of the BinaxNow Influenza A&B rapid antigen test (RAT) in emergency department (ED) patients.
We prospectively enrolled a systematic sample of ED patients older than 6 months with acute respiratory symptoms or nonlocalizing fever during 3 consecutive influenza seasons (2008-2011). Nasal and throat swabs collected by research personnel were tested for influenza by real-time reverse transcription-polymerase chain reaction (RT-PCR). Clinicians independently ordered RATs during clinical care; these specimens were collected by clinical staff and tested for influenza using the BinaxNow RAT. Patients with both a research RT-PCR and clinical RAT were included in the study. Rapid antigen test diagnostic performance was evaluated using RT-PCR as a criterion standard, with preplanned, stratified analysis for subject age, duration of symptoms, influenza subtype, and polymerase chain reaction cycle threshold, which provides a semiquantitative estimate of viral load.
Of 561 subjects enrolled, 131 (23.4%) had a positive RT-PCR, and 37 (6.6%) had a positive RAT. Overall, RAT performance included sensitivity of 24.4% (95% confidence interval [CI], 17.5%-32.9%), specificity of 98.8% (95% CI, 97.1%-99.6%), positive predictive value of 86.5% (95% CI, 70.4%-94.9%), negative predictive value of 81.1% (95% CI, 77.4%-84.3%). Rapid antigen test sensitivities were low for all categories of subject age, symptom duration, influenza subtype, and cycle threshold.
The BinaxNow RAT demonstrated high specificity and poor sensitivity in ED patients selected by treating clinicians for influenza testing. A negative RAT is a poor predictor for the absence of influenza in the ED and should not be used as a criterion to withhold antiviral medications.
本研究旨在评估 BinaxNow 流感 A&B 快速抗原检测（RAT）在急诊科（ED）患者中的诊断性能。
我们前瞻性纳入了 3 个连续流感季节（2008-2011 年）期间 6 个月以上、出现急性呼吸道症状或非定位性发热的 ED 患者系统样本。由研究人员采集的鼻拭子和咽拭子用于流感的实时逆转录聚合酶链反应（RT-PCR）检测。临床医生在临床护理过程中独立开具 RAT 检测医嘱；这些标本由临床工作人员采集，并使用 BinaxNow RAT 进行流感检测。同时进行研究 RT-PCR 和临床 RAT 的患者被纳入研究。采用 RT-PCR 作为标准对快速抗原检测的诊断性能进行评估，并进行了针对患者年龄、症状持续时间、流感亚型和聚合酶链反应循环阈值的分层分析，该分析提供了病毒载量的半定量估计。
561 例纳入患者中，131 例（23.4%）的 RT-PCR 检测结果为阳性，37 例（6.6%）的 RAT 检测结果为阳性。总体而言，RAT 的性能包括：敏感性 24.4%（95%CI，17.5%-32.9%）、特异性 98.8%（95%CI，97.1%-99.6%）、阳性预测值 86.5%（95%CI，70.4%-94.9%）、阴性预测值 81.1%（95%CI，77.4%-84.3%）。对于所有患者年龄、症状持续时间、流感亚型和循环阈值类别，RAT 的敏感性均较低。
在急诊科患者中，BinaxNow RAT 在治疗医生选择进行流感检测时表现出高特异性和低敏感性。阴性 RAT 并不能很好地预测急诊科中不存在流感，不应作为不使用抗病毒药物的标准。
