Abstract

The reliability of the Mycobacteria Growth Indicator Tube (MGIT [BBL]) for rapid drug susceptibility testing of Mycobacterium avium complex (MAC) isolates was evaluated. MICs of amikacin, clarithromycin, clofazimine, ethambutol, and rifabutin were determined by the MGIT system for 16 MAC strains. The results were compared with those obtained by the BACTEC broth macrodilution method. The turnaround times were 6 to 8 days (median, 7 days) for the MGIT and 5 to 7 days (median, 6 days) for the BACTEC system. Agreements with BACTEC system-determined MICs, within +/-1 log2 dilution, were 100, 100, 88, 63, and 44% for amikacin, clofazimine, rifabutin, clarithromycin, and ethambutol, respectively. Within +/-2 log2 dilutions, agreement with BACTEC system-determined MICs increased to 100% for all the tested drugs. In addition, if MGIT-determined MICs were evaluated according to the thresholds adopted for the interpretation of BACTEC system-determined ones, ethambutol was the only drug for which susceptible strains were frequently misclassified as resistant. It is concluded that the MGIT system is a promising, nonradiometric alternative to the BACTEC method for rapid susceptibility testing of MAC isolates; however, additional studies are required to confirm our results and to determine the optimal criteria for the interpretation of ethambutol MICs.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.