目的:我们评估了荧光型MTBDR版本2(FTv2;HainLifescience)的能力,第二步实时PCR检测,同时检测结核分枝杆菌复合体(MTBC)DNA和赋予利福平(RIF)和异烟肼(INH)抗性的突变,在患者的肺和肺外样本中,并将其与相应的培养物进行比较。
方法:对来自丹麦(DK)和德国(DE)的1815和432个样品进行了FTv2MTBC评估。在德国样品和来自塞拉利昂的110个样品中评估了RIF和INH抗性突变,随后与基于GenoTypeMTBDR系探针测定和Sanger测序或全基因组测序的表型抗微生物药物敏感性测试和复合参考DNA(CRD)进行比较。
结果:在584[557涂片阴性]丹麦和277[85涂片阴性]德国痰样本中,42[16]和246[54]为文化阳性,44[18]和222[35]为FTv2阳性,提供0.86[0.63]和0.98(DK)的FTv2灵敏度和特异性,0.90[0.65]和1.00(DE),分别。伯爵,敏感性,所有肺样本的特异性分别为1434、0.79和0.99(DK)和347、0.86和1.00(DE),分别;对于肺外样本,381、0.33、0.99(DK)和83、0.50和1.00(DE)。有效计数,灵敏度,与CRD相比,检测耐药突变的特异性分别为RIF355,0.99,0.96和INH340,1.00和0.98.
结论:FTv2可靠地检测肺和肺外样本中的MTBCDNA,并检测inhA启动子中INH和RIF抗性的抗性突变,katG,和rpoB基因。
OBJECTIVE: We evaluated the ability of FluoroType MTBDR version 2 (FTv2; Hain Lifescience), a second-step real-time PCR assay, to simultaneously detect Mycobacterium tuberculosis complex (MTBC) DNA and mutations conferring resistance to rifampicin (RIF) and isoniazid (INH), in pulmonary and extrapulmonary samples from patients and compared them with corresponding cultures.
METHODS: FTv2 MTBC was evaluated on 1815 and 432 samples from Denmark (DK) and Germany (DE), respectively. RIF and INH resistance mutations were assessed in the German samples and 110 samples from Sierra Leone and subsequently compared to phenotypic antimicrobial susceptibility testing and a composite reference DNA (CRD) based on the GenoType MTBDR line-probe assay and Sanger sequencing or whole-genome sequencing.
RESULTS: Of the 584 (557 smear-negative) Danish and 277 (85 smear-negative) German sputum samples, 42 (16) and 246 (54) were culture positive, and 44 (18) and 222 (35) were FTv2 positive, providing an FTv2 sensitivity and specificity of 0.86 (0.63) and 0.98 (DK), 0.90 (0.65) and 1.00 (DE), respectively. The count, sensitivities, and specificities for all pulmonary samples were 1434, 0.79, and 0.99 (DK) and 347, 0.86, and 1.00 (DE), respectively; for extrapulmonary samples, 381, 0.33, 0.99 (DK) and 83, 0.50, and 1.00 (DE). The valid count, sensitivity, and specificity compared with CRD for detecting resistance mutations were RIF 355, 0.99, 0.96, and INH 340, 1.00, and 0.98, respectively.
CONCLUSIONS: FTv2 reliably detects MTBC DNA in pulmonary and extrapulmonary samples and detects resistance mutations for INH and RIF resistance in inhA promoter, katG, and rpoB genes.