Lucey B, Blake L, Watson M, McIlhagga A, Quinn N, Corcoran G D, Ratnaraja N, Swindells J
Dept. of Biological Sciences, Cork Institute of Technology, Cork, Ireland.
Dept. of Clinical Microbiology, Cork University Hospital, Wilton, Cork, Ireland.
Anaerobe. 2018 Feb;49:53-57. doi: 10.1016/j.anaerobe.2017.12.006. Epub 2017 Dec 18.
The comparatively high cost of laboratory detection methods for Clostridium difficile infection (CDI) coupled to a low prevalence rate has resulted in testing algorithms that use cheaper and relatively sensitive screening methods, followed by more specific confirmatory methods. The aim of this prospectively-conducted study from two centres in the UK, and one in the Republic of Ireland was to determine the efficacy of the EntericBio realtime C. difficile Assay (EBCD) for the detection of toxigenic C. difficile in stool samples. The EBCD was compared to the in-use testing methods for Clostridium difficile (CD) detection in each centre. In the two UK centres, the EBCD was compared to the C.diff Quik Chek Complete kit (Techlab), and discrepancies were tested further using The XpertC. difficile PCR assay (Cepheid) and PCR ribotyping after cultivation using the spore culture method, respectively. In the Irish centre, EBCD comparison was to an algorithm of C. DIFF CHEK™-60 test (Techlab) for screening followed by C. difficile Premier ™ Toxins A&B assay (Meridian Bioscience) in the case of positive results; discrepancies were tested using the XpertC. difficile PCR assay. In a retrospective analysis of data, a total of 947 stool samples were tested, of which eight (0.8%) proved inhibitory to the EBCD assay. Of the 939 valid tests conducted, reported sensitivities of the EBCD were 94.7%, 100% and 97.9%, respectively; specificities were 99.6%, 100% and 100%, respectively; positive predictive values were 94.7%, 100% and 100%, respectively, and negative predictive values were 99.6%, 100% and 99.8%, respectively. The CD positivity rates in the current study ranged between 6.6% and 8.2%.
艰难梭菌感染（CDI）实验室检测方法成本相对较高，加之患病率较低，因此产生了一些检测算法，这些算法先使用成本较低且相对敏感的筛查方法，随后采用更具特异性的确认方法。这项在英国两个中心和爱尔兰共和国一个中心前瞻性开展的研究，旨在确定EntericBio艰难梭菌实时检测法（EBCD）检测粪便样本中产毒艰难梭菌的效能。将EBCD与各中心现用的艰难梭菌（CD）检测方法进行比较。在英国的两个中心，将EBCD与艰难梭菌快速检测完整试剂盒（Techlab）进行比较，差异分别使用Xpert艰难梭菌PCR检测法（Cepheid）以及采用孢子培养法培养后进行PCR核糖分型进一步检测。在爱尔兰中心，EBCD与先用C. DIFF CHEK™-60检测法（Techlab）进行筛查、结果呈阳性时再用艰难梭菌毒素A&B Premier™检测法（Meridian Bioscience）的算法进行比较；差异采用Xpert艰难梭菌PCR检测法进行检测。在对数据的回顾性分析中，共检测了947份粪便样本，其中8份（0.8%）对EBCD检测法有抑制作用。在进行的939次有效检测中，EBCD报告的灵敏度分别为94.7%、100%和97.9%；特异性分别为99.6%、100%和100%；阳性预测值分别为94.7%、100%和100%，阴性预测值分别为99.6%、100%和99.8%。本研究中CD阳性率在6.6%至8.2%之间。
