Nevada State Public Health Laboratory, Reno, NV, United States.
University of Nevada, Reno, School of Medicine, Department of Microbiology and Immunology, Reno, NV, United States.
J Clin Virol. 2020 Aug;129:104501. doi: 10.1016/j.jcv.2020.104501. Epub 2020 Jun 10.
As the demand for laboratory testing for SARS-CoV-2 increases, additional varieties of testing methodologies are being considered. While real time polymerase chain reaction (RT-PCR) has performed as the main method for virus detection, other methods are becoming available, including transcription mediated amplification (TMA). The Hologic Aptima SARS-CoV-2 Assay utilizes TMA as a target amplification mechanism, and it has only recently received Emergency Use Authorization (EUA) by the Food and Drug Administration (FDA).
We sought to compare the sensitivity and specificity of the Aptima SARS-CoV-2 Assay to RTPCR as a means of SARS-CoV-2 detection in a diagnostic setting.
We performed a limit-of-detection study (LoD) to assess the analytical sensitivity of TMA and RT-PCR. This preceded a comparison of the methods using previously evaluated clinical specimens (nasopharyngeal swabs) using 116 human specimens tested by both methodologies. Specimens included sixty-one (61) specimens found reactive by real-time PCR, fifty-one (51) found non-reactive, and four (4) deemed inconclusive.
The Aptima SARS-CoV-2 Assay showed a markedly higher analytical sensitivity than RT-PCR by LoD study. Evaluation of clinical specimens resulted in fewer inconclusive results by the SARS-CoV-2 assay, leading to potentially higher clinical sensitivity.
Higher analytical sensitivity may explain TMA's ability to ascertain for the presence of SARS-CoV-2 genome in human specimens deemed inconclusive by real-time PCR. TMA provides an effective, highly sensitive means of detection of SARS-CoV-2 in nasopharyngeal specimens.
随着对 SARS-CoV-2 实验室检测需求的增加,人们正在考虑更多种类的检测方法。虽然实时聚合酶链反应(RT-PCR)已成为病毒检测的主要方法,但其他方法也在不断涌现,包括转录介导扩增(TMA)。Hologic Aptima SARS-CoV-2 检测利用 TMA 作为靶扩增机制,最近才获得美国食品和药物管理局(FDA)的紧急使用授权(EUA)。
我们旨在比较 Aptima SARS-CoV-2 检测与 RT-PCR 作为 SARS-CoV-2 检测手段的敏感性和特异性。
我们进行了一项检测限研究(LoD),以评估 TMA 的分析敏感性和 RT-PCR。在此之前,我们使用 116 份经两种方法检测的临床评估标本(鼻咽拭子)进行了方法比较。标本包括 61 份实时 PCR 检测呈反应性的标本、51 份非反应性标本和 4 份结果不确定的标本。
通过 LoD 研究,Aptima SARS-CoV-2 检测显示出比 RT-PCR 更高的分析敏感性。对临床标本的评估导致 SARS-CoV-2 检测的不确定结果更少,从而可能提高了临床敏感性。
更高的分析敏感性可能解释了 TMA 能够在实时 PCR 检测结果不确定的人类标本中确定 SARS-CoV-2 基因组的存在。TMA 提供了一种有效、高度敏感的检测鼻咽标本中 SARS-CoV-2 的方法。