Department of Biomedicine and Prevention, Tor Vergata University, 00133 Rome, Italy; Genomic Medicine Laboratory UILDM, IRCCS Santa Lucia Foundation, 00179 Rome, Italy.
Genomic Medicine Laboratory UILDM, IRCCS Santa Lucia Foundation, 00179 Rome, Italy.
Int J Infect Dis. 2021 Jul;108:187-189. doi: 10.1016/j.ijid.2021.04.048. Epub 2021 Apr 18.
The present study compared the performance of the Lumipulse G Sars-CoV-2 Ag kit with the TaqPath COVID-19 RT-PCR CE IVD kit.
The study was conducted on 4266 naso-oropharyngeal swabs. Samples were subjected to antigen RT-PCR tests for the detection of Sars-CoV-2 and related variants. Statistical analyses were conducted in R software.
We found 503 positives (including 138 H69-V70 deletion carriers) and 3763 negatives by RT-PCR, whereas 538 positives and 3728 negatives were obtained by antigen testing. We achieved empirical and binormal AU-ROCs of 0.920 and 0.990, accuracy of 0.960, sensitivity of 0.866, specificity of 0.973, positive and negative predictive values of 0.810 and 0.980. We obtained a positive correlation between viral loads and antigen levels (R = 0.81), finding a complete concordance for high viral loads (log copies/mL > 5.4). Antigen levels > 222 pg/mL were found to be reliable in assigning positive samples (p < 0.01). Concerning variant carriers, antigen test detected them with the same accuracy as other positive samples.
Molecular and antigen tests should be evaluated regarding the prevalence of the area. In case of low prevalence, antigen testing can be employed as a first-line screening for the timely identification of affected individuals with high viral load, also if carriers of Sars-CoV-2 variants.
本研究比较了 Lumipulse G SARS-CoV-2 Ag 试剂盒与 TaqPath COVID-19 RT-PCR CE IVD 试剂盒的性能。
本研究共纳入 4266 例鼻咽拭子样本。对样本进行抗原 RT-PCR 检测，以检测 SARS-CoV-2 及相关变异株。统计分析在 R 软件中进行。
通过 RT-PCR 检测到 503 例阳性（包括 138 例 H69-V70 缺失携带者）和 3763 例阴性，而抗原检测得到 538 例阳性和 3728 例阴性。我们获得了经验和双正态 AU-ROC 分别为 0.920 和 0.990、准确率为 0.960、灵敏度为 0.866、特异性为 0.973、阳性和阴性预测值分别为 0.810 和 0.980。我们发现病毒载量与抗原水平之间存在正相关关系（R = 0.81），对于高病毒载量（log 拷贝/mL > 5.4），发现完全一致。抗原水平 > 222 pg/mL 被认为可以可靠地将阳性样本分类（p < 0.01）。对于变异株携带者，抗原检测与其他阳性样本的检测结果具有相同的准确性。
分子和抗原检测应根据检测地区的流行情况进行评估。在低流行率的情况下，抗原检测可作为一线筛查方法，及时识别具有高病毒载量的受感染个体，也可识别 SARS-CoV-2 变异株携带者。
