Abstract: Objective To study the BACTEC MGIT 960 liquid culture method and the CLSI M24-A broth microdilution method for rapid susceptibility testing the significance of non-tuberculous mycobacteria. Methods The BACTEC MGIT 960 liquid culture broth microdilution method combined rapid susceptibility testing,and L-J solid culture method combined the absolute concentration susceptibility method were respectively used in 48 strains with nontuberculous mycobacteri,the culture time and sensitivity reporting period of two combination methods were compared. Results The average positive report time in 48 strains of nontuberculous mycobacteria culture with BACTEC MGIT 960 instrument was(7. 0 ± 5. 3)d,while that of L-J media was(17. 5 ± 10. 2)d,in comparison the results of two methods were significantly different( P ﹤0 . 05 ),the reported time of broth microdilution France results was 7 -14 d,the report time of L-J solid susceptibility test was 28d,the comparison showed significant difference,two kinds of susceptibility testing methods for the same type of drug resistance rate analysis showed no significant difference( P﹥0 . 05 ),broth microdilution method can detect more types of drugs than the L-J method. Conclusion BACTEC MGIT 960 liquid culture broth microdilution method combined rapid susceptibility testing has obvious advantages over L-J solid culture method and the absolute concentration susceptibility method in the incubation time and susceptibility results reporting time types.

Key words: nontuberculous mycobacteria, microbial sensitivity tests, bacteriological techniques