Objective       To detect the feasibility and efficiency of newly self-designed DNA microarray for rapid detection of resistance to streptomycin (SM)

ethambutol (EMB)

levofloxacin (LVFX)

amikacin (AMK) and capreomycin (CMP) in spinal tuberculosis.       Methods       The new DNA microarray was designed to test the resistance-determining regions in rrs and rpsL (SM)

embB (EMB)

gyrA and gyrB (LVFX)

and rrs (AMK and CMP). A set of 111 drug-resistant Mycobacterium tuberculosis strains

and 26 drug sensitive Mycobacterium tuberculosis strains with full clinical data and sensitivity test results were tested by the new DNA microarray and by DNA sequencing after inactivation

nucleic acid extraction

PCR amplification

chip hybridization

washing and scanning interpretation. The sensitivity and specificity were evaluated.       Results        The average detection time was 20.1±1.2 h (ranged from 18 to 23 h). The sensitivity of the MTBDR test was 90.36%

61.90%

94.59%

66.00% and 65.52% for SM/EMB/LVFX/AMK/CPM respectively

and their specificity was 70.37%

58.11%

58.00%

91.95% and 80.56%

respectively. All 26 drug sensitive Mycobacterium tuberculosis strains were identified as wild type

and the specificity of these wild type strains was 100% for all 5 drugs.       Conclusion       This new DNA microarray is a rapid approach of good biosafety and high sensitivity and specificity in resistance test of first and second line MTB drug for the isolated Mycobacterium tuberculosis strains

and is satisfying in clinical practice for rapid diagnosis of drug-resistant Mycobacterium tuberculosis strains.