ABSTRACT
Objective To establish a method of judge the pyrazinamide(PZA) susceptibility for Mycobacterium tuberculosis(MTB) with 24-hole micro-liquid culture silica gel color plate,and evaluate the clinical application value of this method.Methods According to the result of MGIT960,to detect PZA drug susceptibility for 30 MTB clinical isolates of whose PZA susceptibility were known with silica gel color plate.The effects of different pH value,different inoculation concentrations on the results were observed,and the optimum detection conditions were discussed.Finally,the 98 MTB clinical isolated of whose PZA susceptibility were unknown were simultaneously detected by gel color plate and MGIT960,the sensitivity,specificity and accuracy were judged by PZA drug sensitivity.Results The best pH was 5.8-5.9 and the best concentration was 2.5×10-1 mg/mL in gel color plate.The best results were read after 7-14 d.The sensitivity,specificity and accuracy were 95.50%,96.30%,and 98.21% respectively just at PZA critical concentration was 100 μg/mg.The sensitivity,specificity and accuracy were 90.90%,92.59%,and 91.84% respectively just at PZA critical concentration was 200 μg/mg.Conclusion The PZA susceptibility for MTB with 24-hole micro-liquid culture silica gel color plate is accurate,rapid,low-cost and simple.