Meir Medical Center, Kfar Saba, Israel.
National Center for Infection Control, Ministry of Health, Tel-Aviv, Israel.
Clin Microbiol Infect. 2017 Aug;23(8):567-572. doi: 10.1016/j.cmi.2017.02.016. Epub 2017 Feb 20.
Rapid and accurate detection of Clostridium difficile in stool affects patient treatment and containment efforts. Detection of C. difficile toxin genes using nucleic acid amplification techniques (NAAT) is part of a multistep algorithm. Our objective was to directly compare the diagnostic accuracy and applicability of six commercial C. difficile NAAT.
Two hundred ten specimens were analysed in parallel by six commercial NAAT. Toxigenic culture was used as a reference method.
We analysed 98 positive and 112 negative samples. The Xpert C. difficile had 99% sensitivity (95% confidence interval (CI) 94.45-99.97), followed by Simplexa C. difficile Universal Direct 95% (95% CI 88.49-98.32), Illumigene C. difficile, and Quidel AmpliVue C. difficile, both 93% (95% CI 85.84-97.08), and BDmax Cdiff and GenomEra C. difficile, both 92% (95% CI 84.55-96.41). All assays had very high specificity (>99%). Invalid results requiring retesting were the highest in GenomEra (6.7%; 14/210) and BDmax (4.3%; 9/210), followed by AmpliVue (1.4%; 3/210) and Xpert (0.96%; 2/210). No retesting was required with Simplexa and Illumigene. The turnaround time was the shortest for the Illumigene and Xpert and the longest for BDmax, mostly due to the different reaction times of assays. Total hands-on time was comparable for all six assays.
All assays had high sensitivity and specificity. The differences in turnaround time, repeat testing rates and platform characteristics could help laboratories decide which assay would integrate better in their setting and to better select a molecular platform for C. difficile detection.
快速准确地检测粪便中的艰难梭菌会影响患者的治疗和控制效果。使用核酸扩增技术（NAAT）检测艰难梭菌毒素基因是多步骤算法的一部分。我们的目的是直接比较六种商业艰难梭菌 NAAT 的诊断准确性和适用性。
通过六种商业 NAAT 平行分析 210 份标本。以产毒培养为参考方法。
我们分析了 98 份阳性和 112 份阴性样本。Xpert C. difficile 的灵敏度为 99%（95%置信区间[CI]94.45-99.97），紧随其后的是 Simplexa C. difficile Universal Direct，灵敏度为 95%（95%CI88.49-98.32），Illumigene C. difficile 和 Quidel AmpliVue C. difficile 的灵敏度均为 93%（95%CI85.84-97.08），BDmax Cdiff 和 GenomEra C. difficile 的灵敏度均为 92%（95%CI84.55-96.41）。所有检测方法的特异性均非常高（>99%）。需要重新检测的无效结果在 GenomEra（6.7%；210 份中的 14 份）和 BDmax（4.3%；210 份中的 9 份）最高，其次是 AmpliVue（1.4%；210 份中的 3 份）和 Xpert（0.96%；210 份中的 2 份）。Simplexa 和 Illumigene 不需要重新检测。Illumigene 和 Xpert 的周转时间最短，BDmax 的周转时间最长，主要是因为检测的反应时间不同。所有六种检测方法的总操作时间相当。
所有检测方法均具有高灵敏度和特异性。周转时间、重复测试率和平台特征的差异可以帮助实验室决定哪种检测方法更适合其环境，并更好地选择用于艰难梭菌检测的分子平台。
