Multicenter Evaluation of Bactec MGIT 960 System for Second-Line Drug Susceptibility Testing of Mycobacterium tuberculosis Complex

Microbial Diseases Laboratory, CDPH, 850 Marina Bay Parkway, Richmond, CA 94804, USA.
Journal of clinical microbiology (Impact Factor: 4.23). 10/2009; 47(11):3630-4. DOI: 10.1128/JCM.00803-09
Source: PubMed

ABSTRACT The Bactec MGIT 960 system for testing susceptibility to second-line drugs was evaluated with 117 clinical strains in a multicenter study. The four drugs studied were levofloxacin, amikacin, capreomycin, and ethionamide. The critical concentration established for levofloxacin and amikacin was 1.5 microg/ml, that established for capreomycin was 3.0 microg/ml, and that established for ethionamide was 5.0 microg/ml. The overall level of agreement between the agar proportion method and the MGIT 960 system was 96.4%, and the levels of agreement for the individuals drugs were 99.1% for levofloxacin, 100% for amikacin, 97.4% for capreomycin, and 88.9% for ethionamide. The rate of reproducibility of the drug susceptibility testing results between the participating laboratories was 99.5%.

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