Xpert MTB/RIF技术在结核分枝杆菌利福平耐药性快速检测中的价值

目的探讨Xpert MTB/RIF技术在结核分枝杆菌(MTB)快速检测及利福平耐药检测中的价值。方法收集1 562例初诊疑似肺结核患者痰液样本,同时采用Xpert MTB/RIF法、液体培养法和涂片抗酸染色法进行检测,评价Xpert MTB/RIF法的检测敏感性和特异性。以液体培养法为标准,分析Xpert MTB/RIF法检测涂片抗酸染色法阳性、阴性标本的敏感性和特异性。将188例液体培养阳性样本进行分枝杆菌菌群鉴定和药物敏感性试验,评价Xpert MTB/RIF法检测MTB及其对利福平耐药的敏感性和特异性。结果 Xpert MTB/RIF法与液体培养法检测结果的符合率为93.92%(χ~2=3.55,P0.05),与涂片抗酸染色法的符合率为89.44%(χ~2=48.51,P0.001)。以液体培养法为标准,XpertMTB/RIF法的检测敏感性为82.41%(328/398)、特异性为97.85%(1 139/1 164),2种方法差异无统计学意义(χ~2=3.55,P0.05);XpertMTB/RIF法鉴定188例液体培养阳性样本菌群种类的敏感性为91.23%(156/171)、特异性为88.24%(15/17)、准确性为90.96%(171/188),与液体培养法比较差异无统计学意义(χ~2=4.109,P0.05);Xpert MTB/RIF法检测利福平耐药的敏感性为82.35%(14/17)、特异性为99.35%(1/154),与传统比例法药物敏感性试验结果比较,差异无统计学意义(χ~2=0.138,P0.05)。结论 Xpert MTB/RIF技术可快速检测MTB及其对利福平的耐药性,敏感性和特异性较好,具有较高的临床应用价值。     

Xpert MTB/RIF技术在MTB检测中的应用价值

目的探讨Xpert结核分枝杆菌(MTB)/利福平(RIF)技术在结核病诊断中的临床应用价值。方法采用Xpert MTB/RIF技术、抗酸染色法和培养法同时检测302例确诊结核病的患者样本,对检测结果进行比较。结果所有样本均采用Xpert MTB/RIF技术、抗酸染色法和培养法3种方法进行检测,其中痰样本阳性率分别为53.9%、33.0%和37.2%;灌洗液阳性率分别为65.9%、22.7%和29.5%;胸水阳性率分别为16.4%、1.5%和3.0%。Xpert MTB/RIF技术的阳性率明显高于抗酸染色法和培养法(P均0.01),抗酸染色法与培养法之间差异无统计学意义(P均0.05)。不同类型样本采用Xpert MTB/RIF技术检测的阳性率依次为:灌洗液[65.9%(29/44)]痰样本[53.9%(103/191)]胸水[16.4%(11/67)]。Xpert MTB/RIF技术和比例法药物敏感性试验检测RIF的耐药率分别为22.1%(19/86)和20.9%(18/86),二者间差异有统计学意义(P=0.00);2种方法所得结果的一致率为96.5%(83/86)。结论 Xpert MTB/RIF技术检测MTB与抗酸染色法、培养法相比较,具有快速、简单、敏感性高等优点,有良好的应用前景。     

Xpert MTB/RIF Ultra在结核分枝杆菌及利福平耐药检测中的价值

目的通过与Xpert MTB/RIF比较,评价Xpert MTB/RIF Ultra在结核分枝杆菌及利福平耐药检测中的价值。方法选取出现肺结核症状的患者,根据是否确诊肺结核以及治疗情况分为结核检测组(CDG)和耐药结核组(DRG)。分别采用Xpert MTB/RIF和Xpert MTB/RIF Ultra检测2组患者的痰标本,以MGIT960液体培养作为参考方法,比较2种方法在结核分枝杆菌及利福平耐药检测中的敏感性和特异性。结果 Xpert MTB/RIF Ultra在结核分枝杆菌检测中的敏感性(96.1%)高于Xpert MTB/RIF(85.2%),特异性相同;Xpert MTB/RIF Ultra在抗酸染色涂片阴性患者的结核病检测中敏感性(75.5%)明显高于Xpert MTB/RIF(22.6%)。结论 Xpert MTB/RIF Ultra在结核病患者尤其是在抗酸染色涂片阴性患者结核病检测中的价值优于Xpert MTB/RIF。     

Xpert MTB/RIF在早期诊断结核性脑膜炎中的临床应用价值

目的探讨结核性脑膜炎/利福平耐药基因检测(Xpert MTB/RIF)在早期诊断结核性脑膜炎(TBM)中的临床应用价值。方法选取该院2015年2月至2016年12月收治的130例中枢神经系统感染患者,其中65例TBM患者作为TBM组,65例非TBM患者作为非TBM组。对所有患者的脑脊液标本分别进行结核分枝杆菌抗酸染色、罗氏固体培养以及Xpert MTB/RIF检测,比较检测结果。结果以临床诊断为金标准,Xpert MTB/RIF检测TBM的灵敏度为43.08%,特异度为100.00%;固体培养法检测TBM的灵敏度为58.46%,特异度为98.46%;抗酸染色法检测TBM的灵敏度为9.23%,特异度为100.00%。以传统比例法药敏试验结果为金标准,Xpert MTB/RIF检测利福平耐药的灵敏度为88.89%,特异度为98.35%。结论 Xpert MTB/RIF是一种检测MTB及患者是否对利福平耐药的诊断新技术,具有快速、直接、可靠、特异度高的优点。     

Xpert MTB/RIF检测痰标本结核分枝杆菌与利福平耐受性的临床应用研究

目的分析Xpert MTB/RIF方法用于临床快速检测结核分枝杆菌(MTB)与利福平耐受性的临床意义。方法收集2015年1-12月在惠州市结核病防治研究所及5个县区医院结核科就诊的肺结核患者痰标本552例,进行涂片镜检、Xpert MTB/RIF核酸检测和改良罗氏培养,并对培养阳性者进行药敏实验。评价各种方法 MTB检测灵敏度与特异度,对比传统药敏方法和Xpert MTB/RIF检测利福平耐药性的结果并分析。结果 Xpert MTB/RIF与改良罗氏培养法对MTB检测结果相比,敏感度95.3%、特异度93.1%;耐药性对比结果中,所有阳性标本中利福平耐药的敏感度82.1%,特异度97.8%;Xpert MTB/RIF检测MTB分级与改良罗氏培养分级一致性分析中,kappa=0.688,提示两者结果具有良好的一致性。结论 Xpert MTB/RIF可用于临床早期快速检测结核分枝杆菌与利福平耐药检测的筛查,有利于临床快速决策。     

Xpert MTB/RIF检测技术诊断结核病及其耐药的研究

目的探讨多色巢式实时荧光定量核酸扩增(Xpert MTB/RIF)检测技术在初诊疑似肺结核患者中的诊断价值及其耐药性。方法收集2015年1-6月在上海市松江区中心医院就诊的初诊疑似肺结核患者430例,对其痰标本同时进行痰涂片抗酸染色、MGIT 960液体分枝杆菌培养和Xpert MTB/RIF检测,比较3种方法诊断结核病的阳性率和符合度。同期将其中91例液体培阳的标本送至上海市疾病预防控制中心(CDC)进行分枝杆菌菌群鉴定(PNB法、TCH法和28℃培养试验)和一线抗结核药物(异烟肼、利福平、链霉素和乙胺丁醇)的敏感性试验(传统比例法),以上海市CDC鉴定结果为标准,分析Xpert MTB/RIF检测方法的敏感度、特异度和准确度及其耐药性。结果 430例患者中,痰涂片抗酸染色、液体培养和Xpert MTB/RIF 3种检测方法的分枝杆菌检出率分别为14.19%、26.74%、22.79%。Xpert MTB/RIF检测法与液体培养法的符合率为89.53%(385/430),与涂片法的符合率为90.93%(391/430)。91例液体培养阳性患者,经上海市CDC菌群鉴定,84例为结核分枝杆菌复合群(MTC),7例为非结核分枝杆菌,Xpert MTB/RIF检测方法的敏感度为77.38%(65/84),特异度为100.00%(7/7),准确度为79.12%(72/91)。Xpert MTB/RIF检测出的4例利福平耐药患者和61例利福平敏感患者与比例法药敏鉴定结果完全一致。结论 Xpert MTB/RIF检测方法阳性率明显高于涂片法,与传统液体培养法有较好的一致性。该方法具有较高的敏感度、特异度和准确度。     

Xpert MTB/RIF检测技术在肺结核实验室诊断中应用价值探析

目的：探讨结核分枝杆菌及利福平耐药检测(Xpert MTB/RIF)在肺结核实验室诊断中的临床价值。方法：选取2020年1月至2022年1月收治的118例疑似肺结核患者作为研究对象,所有疑似患者均采集痰液标本,开展痰培养、痰涂片抗酸染色、Xpert MTB/RIF检测,并以痰培养为金标准,分析痰涂片抗酸染色法、Xpert MTB/RIF检测诊断肺结核的临床价值;采用kappa检验验证痰涂片抗酸染色法、Xpert MTB/RIF检测诊断肺结核与痰培养的一致性。结果：118例疑似患者痰培养检出92例,其中痰涂片抗酸染色法检出80例,检出率为86.96%(80/92);Xpert MTB/RIF检测检出90例,检出率为97.83%(90/92);Xpert MTB/RIF检测检出率高于痰涂片抗酸染色法,差异有统计学意义(χ²=7.731,P=0.005);Xpert MTB/RIF检测诊断肺结核的灵敏度[96.74%(89/92)]、准确度[96.61%(114/118)]及阴性预测值[89.29%(25/28)]高于痰涂片抗酸染色法[84.78%(78/92)、86....     

Xpert MTB/RIF技术在基层定点医院肺结核病诊断中的应用价值

目的探讨Xpert MTB/RIF技术在基层定点医院肺结核病诊断中的应用价值。方法选取本院感染科门诊2014年7月至2015年9月疑似肺结核患者的痰标本185份,分别进行固体培养法、Xpert MTB/RIF检测技术和药敏试验,比较Xpert MTB/RIF检测和传统检测痰液标本中结核分枝杆菌培养及利福平耐药性的敏感度、特异度、阳性预测值、阴性预测值和Kappa值。结果痰结核分枝杆菌培养阳性96份,阳性率为51.9%;以固体培养法作为金标准,Xpert MTB/RIF检测的敏感度94.8%,特异度为87.6%,阳性预测值为89.2%,阴性预测值为94.0%,Kappa值为0.826;以比例法药敏试验作为金标准,Xpert MTB/RIF检测的敏感度为86.7%,特异度为94.9%,阳性预测值为76.5%,阴性预测值为97.4%,Kappa值为0.774。结论 Xpert MTB/RIF检测快速,操作简便,硬件设施要求低,能够有效检测结核分枝杆菌及利福平耐药性,可在基层结核实验室大力推广。     

Xpert MTB/RIF系统在结核分枝杆菌和利福平耐药性快速检测中的应用

目的探讨Xpert MTB/RIF系统在结核分枝杆菌(MTB)及利福平耐药性快速检测中的应用。方法收集2015年4-12月在安徽省胸科医院住院的616例肺结核和可疑患者痰液或肺泡灌洗液(BALF)样本,同时进行Xpert MTB/RIF系统、液体培养法和直接涂片法3种方法检测,以临床诊断为金标准进行统计分析。结果 Xpert MTB/RIF系统、液体培养法和直接涂片法检测MTB的敏感性分别为39.61%(225/568)、36.44%(207/568)和17.78%(101/568),Xpert MTB/RIF系统检测的敏感性与液体培养法有较好的一致性(χ~2=1.21,P0.05),显著高于直接涂片法(χ~2=66.15,P0.05)。在对利福平耐药性的检测中,Xpert MTB/RIF系统检出菌株对利福平的耐药率为19.40%(39/201),Xpert MTB/RIF系统的敏感性和特异性分别为94.59%(35/37)和97.56%(160/164),与液体培养法药物敏感性试验相比,差异无统计学意义(χ~2=0.167,P0.05)。对所有培养阳性物进行利福平耐药基因分析,以测序法作为金标准进行rpo B耐药基因检测,Xpert MTB/RIF系统检测利福平耐药位点以Probe E(58.98%,23/39)为主,测序法以S531L和L533P(62.16%,23/37)为主,2种方法突变位点基本一致(χ~2=0.081,P0.05)。结论 Xpert MTB/RIF系统检测MTB及利福平耐药性具有较高的临床应用价值。     

5种结核分枝杆菌检测方法的临床应用价值研究

目的评价5种结核分枝杆菌检测方法对肺结核的辅助诊断价值。方法统计2018年1-10月在广州医科大学附属第一医院住院的患者,分为临床诊断肺结核患者和临床诊断非结核普通住院患者共209例,用结核培养法、PCR-荧光探针法、结核感染T淋巴细胞酶联免疫斑点试验(T-SPOT.TB)法、抗酸染色法、利福平耐药实时荧光定量核酸扩增检测技术(Xpert MTB/RIF)法分别进行检测,比较这5种方法在临床诊断中的价值。结果结核培养法、抗酸染色法、PCR-荧光探针法、T-SPOT.TB法、Xpert MTB/RIF法阳性率分别为16.8%、23.4%、39.2%、53.0%、52.2%。结核培养法灵敏度为52.17%,特异度为100.00%;抗酸染色法灵敏度为42.45%,特异度为96.67%;PCR-荧光探针法灵敏度为76.00%,特异度为97.98%;T-SPOT.TB法灵敏度为91.67%,特异度为79.80%;Xpert MTB/RIF法灵敏度为99.09%,特异度为100.00%。结论Xpert MTB/RIF法是最值得推荐的方法,也是唯一可以作为诊断结核感染的分子生物学方法,如果能够联合这几种方法,可以快速、准确地对结核感染进行诊治。     

结核性脑膜炎实验室检测新进展的临床评价

目的：评价改良抗酸染色、Xpert M TB／RIF和T‐spot?TB在快速早期诊断结核性脑膜炎（TBM ）中的临床价值。方法选取54例确诊结脑和34例非结脑患者,采用改良抗酸染色和Xpert M TB／RIF检测脑脊液中结核分枝杆菌,用结核感染 T细胞斑点实验（T‐spot?TB）检测静脉血中结核杆菌特异性抗原刺激后产生的效应 T淋巴细胞数量。结果改良抗酸染色检测阳性率72．2％（39／54）,Xpert MTB／RIF检测阳性率16．7％（9／54）,T‐spot?TB敏感性83．3％（45／54）,特异性70．6％（24／34）,阳性预测值81．8％,阴性预测值72．7％,三项联合检测可提高灵敏性。结论脑脊液改良抗酸染色检测简单、快速,Xpert M TB／RIF可及时检测利福平耐药情况,T‐spot?TB敏感性高,有辅助诊断价值。三者联合检测可提高TBM诊断的敏感性和及时性。     

An evaluation of the Xpert MTB/RIF assay and detection of false-positive rifampicin resistance in Mycobacterium tuberculosis

Recent reports suggest that false-positive rifampicin resistance may be assigned by the Xpert MTB/RIF assay. We analysed 169 specimens using the MTB/RIF assay. Using culture as the gold standard, we found that the assay had 100% sensitivity and specificity for detecting M. tuberculosis. However, we found that the assay incorrectly assigned rifampicin resistance in 4/13 (31%) of cases.     

Accuracy and incremental yield of urine Xpert MTB/RIF Ultra versus Determine TB-LAM for diagnosis of pulmonary tuberculosis

The performance of urine Xpert MTB/RIF Ultra (Xpert Ultra) for pulmonary TB diagnosis is unknown. HIV-positive and HIV-negative adults were enrolled at two health facilities in Kampala, Uganda. We compared the accuracy of urine Xpert Ultra and Determine TB-LAM in reference to sputum-based testing (positive Xpert MTB/RIF or culture), and assessed incremental yield. Urine Xpert Ultra had low sensitivity (17.2%, 95% CI 12.3–23.2) but high specificity (98.1%, 95% CI 94.4–99.6). Sensitivity reached 50.0% (95% CI 28.2–71.8) among HIV-positive patients with CD4 <100 cells/μL. Compared to Determine TB-LAM, urine Xpert Ultra was 9.4% (95% CI 3.8–14.9, P = 0.01) more sensitive, and 17.2% (95% CI 4.5–29.8, P = 0.01) more sensitive among HIV-positive patients. However, the incremental sensitivity of urine Xpert Ultra relative to sputum Xpert MTB/RIF was only 1% (95% CI -0.9 to 2.8). Urine Xpert Ultra could be an alternative for patients with advanced HIV infection unable to produce sputum.     

Assessing the utility of the Xpert Mycobacterium tuberculosis/rifampin assay for analysis of bronchoalveolar lavage fluid in patients with suspected pulmonary tuberculosis

BackgroundThere is limited research assessing the utility of the Xpert Mycobacterium tuberculosis/rifampin (MTB/RIF) assay for the analysis of bronchoalveolar lavage fluid (BALF) in Chinese patients with suspected pulmonary tuberculosis (PTB). Thus, our objective was to determine the diagnostic accuracy of the Xpert MTB/RIF assay and evaluate its utility for the determination of rifampicin resistance.MethodsWe retrospectively analyzed BALF from 214 patients with suspected PTB between January 2018 and March 2019. Using mycobacterial culture or final clinical diagnosis as the reference standard, the diagnostic accuracy of the smear microscopy (SM), tuberculosis bacillus DNA (TB‐DNA), Xpert MTB/RIF assay, and the determination of rifampicin resistance based on the Xpert MTB/RIF assay were compared.ResultsAs compared to mycobacterial culture, the sensitivity of the Xpert MTB/RIF assay, SM, and TB‐DNA were 85.5% (74.2%–93.1%), 38.7% (26.6%–51.9%), and 67.7% (54.7%–79.1%), respectively. As compared to the final diagnosis, the specificity of the Xpert MTB/RIF assay, SM, and TB‐DNA were 100.0% (95.9%–100.0%), 94.3% (87.1%–98.1%), and 98.9% (93.8%–100.0%), respectively. The sensitivity and specificity of the rifampicin resistance detection using the Xpert MTB/RIF assay were 100% and 98.0%, respectively, with liquid culture as the reference.ConclusionsThis study demonstrates that the analysis of BALF with the Xpert MTB/RIF assay provides a rapid and accurate tool for the early diagnosis of PTB. The accuracy of diagnosis was superior compared with the SM and TB‐DNA. Moreover, Xpert is a quick and accurate method for the diagnosis of rifampicin‐resistant tuberculosis and can also provide more effective guidance for the treatment of PTB or multidrug‐resistant tuberculosis (MDR‐TB).     

Xpert(®) MTB/RIF for point-of-care diagnosis of TB in high-HIV burden, resource-limited countries: hype or hope?

Despite the identification of Mycobacterium tuberculosis as the cause of tuberculosis (TB) more than a century ago, diagnosing TB in resource-poor countries remains a challenge, especially in people living with HIV. In the past decade, important research investments have been made towards the development of new diagnostics for TB and the Xpert(?) MTB/RIF assay (Cepheid, CA, USA) has emerged as one of the most promising. In this article, we review the current knowledge on Xpert MTB/RIF, discuss the potential value of Xpert MTB/RIF as a point-of-care diagnostic for drug-sensitive and drug-resistant TB, and outline the potential indications for the assay in resource-limited, high-HIV burden settings. We also discuss key research questions that need to be addressed prior to possible large-scale implementation of the assay.     

Detection of Mycobacterium tuberculosis in clinical sputum by a unique gene in MTB strains called Conserved protein TB18.5 (TB18.5)

A rapid and accurate diagnosis increases the treatment effect and decreases the mortality of tuberculosis (TB) patients. The purpose of this study was to establish an accurate, unique, and rapid molecular diagnostic technique to screen Mycobacterium tuberculosis (MTB) from clinical sputum. A unique gene in MTB strains called conserved protein TB18.5 (TB18.5) was selected by bioinformatics analysis. Two pairs of primers were designed to amplify TB18.5 using the nested polymerase chain reaction (PCR) or quantitative real‐time PCR. Nine pathogens and the MTB strain were used to determine the specificity of the TB18.5 gene. The sensitivity assay was performed after optimizing the PCR conditions. The correct fragment was amplified when a 10 copy number template was used. A total of 232 sputum samples were collected from TB patients (from 2019 to 2020) to evaluate the accuracy of the molecular method in this study. MTB was first detected using the BACTEC MGIT‐960 culture test and the Gene Xpert MTB/RIF assay. Totals of 195 (84.05%), 182 (78.45%), and 162 (69.83%) sputum samples were determined to be infected with MTB using nested PCR, the Gene Xpert MTB/RIF assay, and the BACTEC MGIT‐960 culture test, respectively. In summary, a rapid, unique, and sensitive molecular method was established to diagnose TB infection in clinical sputum samples.     

GeneXpert MTB/RIF、MGIT960液体培养法在胸腔积液结核分枝杆菌检测中的应用

目的探讨GeneXpert MTB/RIF、MGIT960液体培养法在胸腔积液结核分枝杆菌检测中的应用。方法回顾性分析386例疑似和确诊结核病患者胸腔积液标本中腺苷脱氨酶(ADA)、GeneXpert MTB/RIF及MGIT960液体培养法的检测结果。以胸腔积液ADA>40 U/L作为鉴别结核性积液的标准,将标本分为3组:第1组为非结核性积液(ADA≤40 U/L,219例),第2组为结核性积液(ADA>40 U/L,145例),第3组为脓性胸腔积液(不能进行ADA检测,22例)。结果在386例患者中,GeneXpert MTB/RIF检测结核分枝杆菌复合群的阳性率为15.54%(60/386),MGIT960液体培养法检测结核分枝杆菌复合群的阳性率为5.44%(21/386),前者检测阳性率明显高于后者(χ²=14.52,P<0.05)。3组中,GeneXpert MTB/RIF检测阳性率分别为3.20%、24.83%和77.27%;MGIT960液体培养法检测阳性率分别为2.74%、8.28%和13.64%。GeneXpert MTB/RIF在结核性积液、脓性胸腔积液中检测结核分枝杆菌复合群的阳性率明显高于MGIT960液体培养法(χ²=14.38、17.97,P<0.05)。将采用MGIT960液体培养法检测为阳性的标本21例进行GeneXpert MTB/RIF检测发现,两种方法检测阳性结果的符合率为52.38%(11/21)。结论GeneXpert MTB/RIF检出结核分枝杆菌复合群的阳性率明显高于MGIT960液体培养法,特别是在结核性积液和脓性胸腔积液中。两种方法联合检测,有助于临床对结核性胸膜炎的早期诊断和治疗。