title: Little difference between minimum inhibitory concentrations of Mycobacterium tuberculosis wild-type organisms determined with BACTEC MGIT 960 and Middlebrook 7H10.
abstract: The MIC wild-type (WT) distribution for Mycobacterium tuberculosis in BACTEC 960 MGIT is not defined, which may result in poor reproducibility for drug susceptibility testing (DST), as several DST methods with different breakpoints are in use. In a comparison between MGIT and Middlebrook 7H10 medium of seven first- and second-line drugs, including 133 MIC determinations of 15 WT isolates, we found an agreement of 91.7% within ± one MIC dilution step. The results confirm the agreement in MIC testing between 7H10 and MGIT and indicate that breakpoints could be harmonized in order to avoid misclassification.
authors: Medical Microbiology, Department of Laboratory Medicine, Malmö, Lund University, Lund, Sweden.
authors: E
authors: E
authors: Sturegård
authors: Clinical Microbiology, MTC - Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden; Department of Microbiology, The University of the West Indies, Kingston, Jamaica.
authors: K A
authors: KA
authors: Ängeby
authors: The Public Health Agency of Sweden, Department of Microbiology, Solna, Sweden.
authors: J
authors: J
authors: Werngren
authors: The Public Health Agency of Sweden, Department of Microbiology, Solna, Sweden.
authors: P
authors: P
authors: Juréen
authors: Clinical Microbiology, MTC - Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
authors: G
authors: G
authors: Kronvall
authors: Clinical Microbiology, MTC - Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
authors: C G
authors: CG
authors: Giske
authors: Department of Clinical Microbiology, Växjö Hospital, Växjö, Sweden; Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
authors: G
authors: G
authors: Kahlmeter
authors: Department of Clinical Microbiology, Kalmar County Hospital, Kalmar, Sweden. Electronic address: tschon@hotmail.com.
authors: T
authors: T
authors: Schön
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology*; D003470:Culture Media / Q000737:chemistry*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods*; D009169:Mycobacterium tuberculosis / Q000187:drug effects*
chemical_list: D000995:Antitubercular Agents; D003470:Culture Media
keywords: Drug susceptibility testing; epidemiological cut off; minimal inhibitory concentration; normalised resistance interpretation; resistance; tuberculosis