Reverse dot blot hybridization of gyrA mutation for rapid detection of Mycobacterium tuberculosis resistance to quinolone

Objective To establish a reverse dot blot hybridization (RDBH) assay for the rapid detection of Mycobacterium tuberculosis resistance to quinolone. Methods Based on the sequence results of gyrA gene and common mutation sites in M. tuberculosis,one wildtype and seven mutant oligonucleotide probes were designed. Meanwhile, conventional drug susceptibility test (DST) and DNA sequencing were performed to evaluate the effect of RDBH assay. Results A total of 59 quinolone resistant M. tuberculosis isolates and 51 quinolone sensitive M. tuberculosis isolates were detected by using DST, DNA sequencing and RDBH assay. Compared with DST results,the sensitivity and specificity of RDBH assay were 69.49% (41/59) and 100%(51/51). Compared with DNA sequencing, the sensitivity, specificity and conformity of RDBH were 97.56% (40/41), 98.55% (68/69) and 98.18%,respectively. Conclusion RDBH is a rapid, simple and efficient assay to detect quinolone resistant M. tuberculosis.