Zikun Huang and Guoliang Xiong contributed equally to this study.
Evaluation of the performance of the microscopic observation drug susceptibility assay for diagnosis of extrapulmonary tuberculosis in China: A preliminary study
Article first published online: 23 DEC 2013
© 2013 The Authors. Respirology © 2013 Asian Pacific Society of Respirology
Volume 19, Issue 1, pages 132–137, January 2014
How to Cite
Huang, Z., Xiong, G., Luo, Q., Jiang, B., Li, W., Xu, X. and Li, J. (2014), Evaluation of the performance of the microscopic observation drug susceptibility assay for diagnosis of extrapulmonary tuberculosis in China: A preliminary study. Respirology, 19: 132–137. doi: 10.1111/resp.12192
(Associate Editor: O Jung Kwon).
- Issue published online: 23 DEC 2013
- Article first published online: 23 DEC 2013
- Accepted manuscript online: 19 SEP 2013 08:47PM EST
- Manuscript Received: 29 JUL 2013
- Manuscript Revised: 29 JUL 2013
- Manuscript Accepted: 29 JUL 2013
- Manuscript Revised: 24 JUL 2013
- Manuscript Revised: 5 JUL 2013
- Manuscript Revised: 3 MAY 2013
- National Natural Science Foundation of China. Grant Number: 81060001
- Foundation of Sci & Tech Research Project of Jiangxi province. Grant Number: 2009BSB11219
- drug susceptibility assay;
Background and objective
While commercial liquid culture techniques have emerged over 20 years ago, Ziehl–Neelsen (ZN) smear microscopy remains the primary method for diagnosis of tuberculosis (TB) in China because of cost considerations. The microscopic observation drug susceptibility (MODS) assay has been evaluated in different parts of the world to determine whether it can give comparable result to commercial liquid techniques. However, most reports detail evaluation of sputum specimens. This study evaluated the performance of MODS assay for detection of Mycobacterium tuberculosis in extrapulmonary specimens in a Chinese population.
A total of 173 samples, including pleural fluid (n = 112) and cerebrospinal fluid (CSF, n = 61) samples, were collected from patients suspected to have extrapulmonary TB and tested by ZN smear microscopy, Lowenstein–Jensen (LJ) culture and the MODS assay. Discordant results among MODS assay and the other two methods were resolved by 90-day follow-up evaluation for all suspected patients.
The sensitivity of the MODS assay on pleural fluid and CSF samples was 20.5% and 37.5%, respectively, while the specificity of MODS assay on both types of samples approximated 100%. The median time to culture results for the MODS and LJ methods was 14 days, 32 days for pleural fluid, and 9 days and 31 days for CSF samples, respectively.
MODS assay is useful to diagnose extrapulmonary TB and may be an effective and affordable method in resource-limited countries.