Background: Rapid molecular methods have been recommended for early detection of drug-resistant tuberculosis (TB).
Objective: To evaluate the performance of the GenoType(®) MTBDRplus assay in routine settings in China.
Methods: Sputum-positive samples were collected consecutively from 1 April to 31 December 2010. MTBDRplus results were compared to those of conventional drug susceptibility testing (DST). The McNemar χ(2) test and κ coefficient were used to assess performance.
Results: Of 427 smear-positive sputum samples collected, conventional DST and MTBDTplus confirmed drug resistance in 326. The sensitivities and specificities for MTBDRplus in detecting isoniazid (INH) and rifampicin (RMP) resistance were respectively 76.47%, 95.44%, 85.94% and 93.13%. The McNemar χ(2) test indicated no significant difference between the two methods (P = 0.106 for INH and P = 0.083 for RMP). The κ values for INH, RMP and multidrug resistance were respectively 0.75, 0.75 and 0.70.
Conclusions: Although the MTBDRplus assay was moderately concordant with conventional DST in detecting INH and RMP resistance, as a prospective rapid molecular method for MDR-TB detection, potential resistant mutations need to be incorporated to improve the accuracy of detection.