Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2010 Jan;48(1):300-1.
doi: 10.1128/JCM.01775-09. Epub 2009 Nov 18.

Potential for erroneous results indicating resistance when using the Bactec MGIT 960 system for testing susceptibility of Mycobacterium tuberculosis to pyrazinamide

Pamela Chedore  1 , Lina Bertucci, Joyce Wolfe, Meenu Sharma, Frances Jamieson
Affiliations

Potential for erroneous results indicating resistance when using the Bactec MGIT 960 system for testing susceptibility of Mycobacterium tuberculosis to pyrazinamide

Pamela Chedore et al. J Clin Microbiol. 2010 Jan.

Abstract

During susceptibility testing of 743 isolates of Mycobacterium tuberculosis to pyrazinamide (PZA) using the Bactec 960 system, 57 (7.7%) isolates showed PZA resistance. Repeat testing of resistant isolates with the Bactec 460 reference method confirmed 33 (4.4%) of these isolates as resistant, and 24 (3.2%) were susceptible. Erroneous results for resistance with the Bactec 960 were confirmed by testing the 24 discordant isolates for pyrazinamidase and mutations in the pncA gene.

PubMed Disclaimer

References

    1. Aono, A., K. Hirano, S. Hamasaki, and C. Abe. 2002. Evaluation of BACTEC MGIT 960 PZA medium for susceptibility testing of Mycobacterium tuberculosis to pyrazinamide (PZA): compared with the results of pyrazinamidase assay and Kypkuto PZA test. Diagn. Microbiol. Infect. Dis. 44:347-352. - PubMed
    1. Becton Dickinson and Company. 1999. Bactec MGIT 960 system user's manual. Becton Dickinson and Company, Sparks, MD.
    1. Clark, R. B., M. A. Lewinski, M. J. Loeffelholz, and R. J. Tibbetts. 2009. Cumitech 31A, Verification and validation of procedures in the clinical microbiology laboratory, p 14. Coordinating ed., S. E. Sharp. ASM Press, Washington, DC.
    1. CLSI/NCCLS. 2003. Susceptibility testing of Mycobacteria, Nocardiae, and other aerobic Actinomycetes, vol. 23, no. 18. Approved standard M24-A. National Committee for Clinical Laboratory Standards, Wayne, PA. - PubMed
    1. Davies, A. P., O. J. Billington, T. D. McHugh, D. A. Mitchison, and S. H. Gillespie. 2000. Comparison of phenotypic and genotypic methods for pyrazinamide susceptibility testing with Mycobacterium tuberculosis. J. Clin. Microbiol. 38:3686-3688. - PMC - PubMed

MeSH terms