title: Evaluation of GeneXpert MTB/RIF for detection of pulmonary tuberculosis at peripheral tuberculosis clinics.
abstract: Tuberculosis is one of the most common infectious diseases in China, while delayed patient finding obstructed disease control, especially for smear-negative patients. The current study was undertaken to evaluate the diagnostic accuracy of GeneXpert MTB/RIF compared with conventional methods in the detection of pulmonary tuberculosis patients. A total of 295 spot sputum samples from confirmed pulmonary tuberculosis patients were evaluated from September 2014 to June 2015. Each sample was examined by acid-fast bacillus smear microscopy, culture and GeneXpert MTB/RIF. The sputum culture on Löwenstein-Jensen (L-J) was considered as the gold-standard. After testing by smear, 68.81% (203/295) was negative and 31.19% (92/295) was positive. As the gold-standard, L-J culture detected 37.97% (112/295) positive of all specimens, while the positivity for GeneXpert MTB/RIF was 46.44% (137/295). Compared with L-J culture, the combined sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for GeneXpert MTB/RIF were 94.64%, 82.97%, 77.37% and 96.18% respectively. For smear-negative specimens, the sensitivity, specificity, PPV and NPV for GeneXpert MTB/RIF were 96.00%, 83.05%, 44.44% and 99.32%; while for smear-positive specimens, the corresponding accuracy values were 94.25%, 80.00%, 98.80% and 44.44%. The findings of study indicated that GeneXpert MTB/RIF assay demonstrated a high sensitivity in detecting Mycobacterium tuberculosis compared to smear method and a high NPV among smear negative patients.
authors.affiliation: Center for Disease Control and Prevention of Jiangsu Province, Nanjing, China. Electronic address: maimai9947@163.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Shao
authors.affiliation: Center for Disease Control and Prevention of Jiangsu Province, Nanjing, China. Electronic address: vickyph@163.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Peng
authors.affiliation: Center for Disease Control and Prevention of Jiangsu Province, Nanjing, China. Electronic address: chencheng128@gmail.com.
authors.forename: Cheng
authors.initials: C
authors.lastname: Chen
authors.affiliation: Center for Disease Control and Prevention of Danyang City, Danyang, China. Electronic address: 2464805541@qq.com.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhu
authors.affiliation: Center for Disease Control and Prevention of Taixing City, Taixing, China. Electronic address: 417997949@qq.com.
authors.forename: Ming
authors.initials: M
authors.lastname: Ji
authors.affiliation: Center for Disease Control and Prevention of Zhangjiagang City, Zhangjiagang, China. Electronic address: jwzjgcdc@126.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Jiang
authors.affiliation: Center for Disease Control and Prevention of Taixing City, Taixing, China. Electronic address: 26821932@qq.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Center for Disease Control and Prevention of Jiangsu Province, Nanjing, China. Electronic address: jszxj@jscdc.cn.
authors.forename: Xiang Jun
authors.initials: XJ
authors.lastname: Zhai
authors.affiliation: Center for Disease Control and Prevention of Jiangsu Province, Nanjing, China. Electronic address: jsjkmck@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
mesh_terms: D000328:Adult; D000368:Aged; D015373:Bacterial Typing Techniques / Q000295:instrumentation / Q000379:methods; D018929:Cell Culture Techniques; D002681:China / Q000453:epidemiology; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000302:isolation & purification*; D011237:Predictive Value of Tests; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology*
keywords: Mycobacterium tuberculosis; Real-time polymerase chain reaction; Smear-negative