Evaluation of the AdvanSure MDR-TB GenoBlot Assay for Detection of Rifampin and Isoniazid Resistant Mycobacterium tuberculosis Complex in Respiratory Specimens

Background: We evaluated the performance of the AdvanSure MDR-TB GenoBlot Assay kit (AdvanSure MDR-TB, LG Life Science, Korea) to detect mutations related to rifampin (RFP)and isoniazid (INH)-resistant Mycobacterium tuberculosis complex in respiratory specimens. Methods: From February 2010 to June 2010, a total of 542 M. tuberculosis clinical isolates were collected from pulmonary tuberculosis patients in six university hospitals across Korea. We analyzed the conventional drug susceptibility testing (DST) and compared the results with those of the AdvanSure MDR-TB. Results: Compared with the conventional DST, the overall agreement rates, sensitivity, and specificity were 98.2% (532/542), 84.6% (33/39), and 99.2% (499/503), respectively, for RFP resistance and 96.1% (521/542), 79.7% (59/74), 98.7% (462/468), respectively, for INH resistance. The three common rpoB mutations were rpoB S531L (53.8%), rpoB D516V (15.4%) and rpoB H526R (7.7%) in RFP-resistant strains. For INH resistance, the katG S315T mutation (58.1%) was the most common, followed by inhA C-15T (23.0%) and katG S315N (4.1%). Conclusion: The AdvanSure MDR-TB showed high concordance with the conventional DST and would be helpful for early detection of RFP and INH resistance, although it requires improved sensitivity. (Korean J Clin Microbiol 2012;15:117-124)