ABSTRACT
We evaluated clinical application effect of gene chip for detection of rifampin (RFP) and isoniazid (INH) resistance in Mycobacterium tuberculosis (MTB).Rifampin and isoniazid drug-resistance gene loci were detected by gene chip with sputum specimens from smear-positive tuberculosis patients and clinical strains,comparing the results of detection.BACTEC MGIT 960 drug susceptibility test results were used as control to evaluate the detection performance of gene chip.The sequences of the polymerase chain reaction products of the rpoB,katG and inhA genes from 999 strains identified as Mycobacterium tuberculosis were determined to confirm the mutations by DNA sequencing.Results showed that 100 cases were identified as nontuberculous mycobacteria by gene chip in the 1 108 cases of smear-positive samples.Among the rest 1 008 samples,there were only 9 cases of microarray results different from BACTEC MGIT960 culture-positive strains,achieving the coincidences of 99.1％.Compared with BACTEC MGIT 960 drug susceptibility test results,the gene chip method displayed a concordance of 98.1 ％ and 94.5 ％ for RFP and INH respectively in the 999 strains.Compared with the DNA sequencing method,the accuracy of gene chip method was 99.6％ for rifampin resistance and 99.8％ for isoniazid resistance.It's concluded that the gene chip technology can quickly and accurately detect rifampin and isoniazid resistance in MTB and can be used directly for the detection of sputum samples.