Department of Laboratory Medicine, Iris Hospitals South, Brussels, Belgium.
Faculty of Medicine, Université libre de Bruxelles, Brussels, Belgium.
J Med Virol. 2021 Apr;93(4):2538-2542. doi: 10.1002/jmv.26782. Epub 2021 Jan 22.
The occurrence of the COVID-19 second-wave outbreak in Europe has pushed laboratories performing molecular SARS-CoV-2 tests to increase their throughput and decrease the result rendering time. In this evaluation, we tested for the first time a new, extraction-free, protocol with the Allplex SARS-CoV-2 Assay RT-qPCR kit on a Nimbus platform. Ninety-one samples, of which 71 previously tested positive with RT-qPCR with extraction were immediately analyzed without extraction, using only a dilution and thermal shock protocol. The positive and negative percentage agreements were respectively 97.2% (95% confidence interval [CI]: 0.90-0.99) and 95.0% (95% CI: 0.76-0.99). The two false negatives observed were very weakly positive with the comparison method. Moderate variations in Ct of the targeted genes were observed (median ± 95% CI): E gene, +2.49 ± 0.44; N gene, +0.98 ± 0.54; RdRP/S genes, +2.64 ± 0.48. On the other hand, the number of tests performed within 24 h raised from 86.4% to 97.8%, the turn-around time decreased from 19:18 to 09:03 (p < .0001), and the number of tests that can be performed per day doubled since this technique was introduced routinely in our laboratory.
欧洲第二波 COVID-19 疫情的爆发促使进行分子 SARS-CoV-2 检测的实验室提高了检测通量并缩短了结果出具时间。在本次评估中，我们首次在 Nimbus 平台上使用 Allplex SARS-CoV-2 检测 RT-qPCR 试剂盒测试了一种新的、无需提取的方案。91 个样本，其中 71 个先前经提取 RT-qPCR 检测为阳性的样本立即进行了无需提取的分析，仅采用稀释和热冲击方案。阳性和阴性符合率分别为 97.2%（95%置信区间[CI]：0.90-0.99）和 95.0%（95%CI：0.76-0.99）。观察到的两个假阴性结果与比较方法相比呈弱阳性。目标基因的 Ct 值存在中等程度的变化（中位数±95%CI）：E 基因，+2.49±0.44；N 基因，+0.98±0.54；RdRP/S 基因，+2.64±0.48。另一方面，24 小时内完成的检测数量从 86.4%增加到 97.8%，周转时间从 19:18 缩短至 09:03（p<0.0001），自从这项技术在我们实验室常规应用以来，每天可以完成的检测数量增加了一倍。
