A feasibility study of the Xpert MTB/RIF test at the peripheral level laboratory in China

• Main Authors: Xichao Ou, Hui Xia, Qiang Li, Yu Pang, Shengfen Wang, Bing Zhao, Yuanyuan Song, Yang Zhou, Yang Zheng, Zhijian Zhang, Zhiying Zhang, Junchen Li, Haiyan Dong, Junying Chi, Jack Zhang, Kai Man Kam, Shitong Huan, Yue Jun, Daniel P. Chin, Yanlin Zhao
• Format: Article
• Language: English
• Published: Elsevier 2015-02-01
• Series: International Journal of Infectious Diseases
• Subjects: Mycobacterium tuberculosis; Xpert MTB/RIF; Rifampin
• Online Access: http://www.sciencedirect.com/science/article/pii/S1201971214016579
• ISSN: 1201-9712; 1878-3511

Objective: To evaluate the performance of Xpert MTB/RIF (MTB/RIF) in the county-level tuberculosis (TB) laboratory in China. Methods: From April 2011 to January 2012, patients with suspected multidrug-resistant tuberculosis (MDR-TB) and non-MDR-TB were enrolled consecutively from four county-level TB laboratories. The detection of Mycobacterium tuberculosis (MTB) by MTB/RIF was compared to detection by Löwenstein–Jensen culture. The detection of rifampin resistance was compared to detection by conventional drug-susceptibility testing. The impact of multiple specimens on the performance of MTB/RIF was also evaluated. Results: A total of 2142 suspected non-MDR-TB cases and 312 suspected MDR-TB cases were enrolled. For MTB detection in suspected non-MDR-TB cases, the sensitivity and specificity of MTB/RIF were 94.4% and 90.2%, respectively. The sensitivity in smear-negative patients was 88.8%. For the detection of rifampin resistance in suspected non-MDR-TB cases, the sensitivity and specificity of MTB/RIF were 87.1% and 97.9%, respectively. For the detection of rifampin resistance in suspected MDR-TB cases, the sensitivity and specificity of MTB/RIF were 87.1% and 91.0%, respectively. Using multiple sputum specimens had no significant influence on the performance of MTB/RIF for MTB detection. Conclusions: The introduction of MTB/RIF could increase the accuracy of detection of MTB and rifampin resistance in peripheral-level TB laboratories in China. One single specimen is adequate for TB diagnosis by MTB/RIF.