Wu Qing, Tu Hongxiang, Dai Yingjie, Wang Yumin, Hu Lijuan
Department of Laboratory Medicine, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
Eur J Clin Microbiol Infect Dis. 2025 Jul 22. doi: 10.1007/s10096-025-05218-1.
Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) rank among the most common sexually transmitted pathogens. Rapid screening and detection of these bacteria are essential to reduce sequelae and prevent transmission. This study evaluated the efficacy of the EasyNAT CT/NG assay, which utilizes cross-priming amplification (CPA) technique for the rapid and simultaneous detection of CT and NG in diverse reproductive tract specimens, achieving diagnosis within 30 min.
The clinical performance of the EasyNAT CT/NG assay in detecting CT and NG was assessed using 198 clinical samples, with results compared to those of conventional in-house Real-Time PCR to determine concordance. Sensitivity was measured using serial dilutions of quantified plasmids and specificity was evaluated by incorporating DNA from 18 common STI pathogens. The assay's suitability as a point-of-care testing (POCT) tool was evaluated with the criteria outlined in Target Product Profiles (TPPs).
The EasyNAT CT/NG assay demonstrated high concordance with Real-Time PCR, with rates of 98.5% for CT and 99.0% for NG. Concordance in urine samples reached 98.6% for CT and 100% for NG, while cervical swabs showed both 97.7% for CT and NG; vaginal and urethral swabs achieved 100% for both pathogens. Among the 198 samples, one urine specimen tested negative for CT by Real-Time PCR but positive by the EasyNAT CT/NG assay, a positive result confirmed by the Cepheid Xpert CT/NG assay. Two cervical swabs, negative for CT and NG by Real-Time PCR, yielded invalid results with the EasyNAT CT/NG assay but were confirmed negative or CT and NG by the Cepheid Xpert CT/NG assay. The EasyNAT CT/NG assay reliably detected CT and NG in turbid specimens, though it may fail with severely hemolytic samples. Its detection limit was 400 copies/mL, with no cross-reactivity observed across 18 other pathogens.
The EasyNAT CT/NG assay offers rapid, sensitive, and specific detection of CT and NG, proving valuable for infection screening and early diagnosis. It shows promise as a rapid POCT method.
沙眼衣原体（CT）和淋病奈瑟菌（NG）是最常见的性传播病原体。对这些细菌进行快速筛查和检测对于减少后遗症和预防传播至关重要。本研究评估了EasyNAT CT/NG检测法的有效性，该检测法利用交叉引物扩增（CPA）技术在不同生殖道标本中快速同时检测CT和NG，可在30分钟内完成诊断。
使用198份临床样本评估EasyNAT CT/NG检测法检测CT和NG的临床性能，并将结果与传统的内部实时荧光定量PCR结果进行比较以确定一致性。通过定量质粒的系列稀释来测量灵敏度，并通过加入18种常见性传播感染病原体的DNA来评估特异性。根据目标产品概况（TPPs）中概述的标准评估该检测法作为即时检测（POCT）工具的适用性。
EasyNAT CT/NG检测法与实时荧光定量PCR显示出高度一致性，CT的一致性率为98.5%，NG的一致性率为99.0%。尿液样本中CT的一致性达到98.6%，NG的一致性达到100%；宫颈拭子中CT和NG的一致性均为97.7%；阴道和尿道拭子中两种病原体的一致性均达到100%。在198份样本中，一份尿液标本经实时荧光定量PCR检测CT为阴性，但经EasyNAT CT/NG检测法为阳性，该阳性结果经赛沛Xpert CT/NG检测法确认。两份宫颈拭子经实时荧光定量PCR检测CT和NG均为阴性，但EasyNAT CT/NG检测法结果无效，不过经赛沛Xpert CT/NG检测法确认为CT和NG阴性。EasyNAT CT/NG检测法能可靠地检测浑浊标本中的CT和NG，不过对于严重溶血的样本可能无法检测。其检测限为400拷贝/毫升，在其他18种病原体中未观察到交叉反应。
EasyNAT CT/NG检测法能快速、灵敏且特异地检测CT和NG，对感染筛查和早期诊断具有重要价值。它有望成为一种快速的即时检测方法。
