title: A Multilaboratory, Multicountry Study To Determine MIC Quality Control Ranges for Phenotypic Drug Susceptibility Testing of Selected First-Line Antituberculosis Drugs, Second-Line Injectables, Fluoroquinolones, Clofazimine, and Linezolid.
abstract: Our objective was to establish reference MIC quality control (QC) ranges for drug susceptibility testing of antimycobacterials, including first-line agents, second-line injectables, fluoroquinolones, and World Health Organization category 5 drugs for multidrug-resistant tuberculosis using a 7H9 broth microdilution MIC method. A tier-2 reproducibility study was conducted in eight participating laboratories using Clinical Laboratory and Standards Institute (CLSI) guidelines. Three lots of custom-made frozen 96-well polystyrene microtiter plates were used and prepared with 2× prediluted drugs in 7H9 broth-oleic acid albumin dextrose catalase. The QC reference strain was Mycobacterium tuberculosis H37Rv. MIC frequency, mode, and geometric mean were calculated for each drug. QC ranges were derived based on predefined, strict CLSI criteria. Any data lying outside CLSI criteria resulted in exclusion of the entire laboratory data set. Data from one laboratory were excluded due to higher MIC values than other laboratories. QC ranges were established for 11 drugs: isoniazid (0.03 to 0.12 μg/ml), rifampin (0.03 to 0.25 μg/ml), ethambutol (0.25 to 2 μg/ml), levofloxacin (0.12 to 1 μg/ml), moxifloxacin (0.06 to 0.5 μg/ml), ofloxacin (0.25 to 2 μg/ml), amikacin (0.25 to 2 μg/ml), kanamycin (0.25 to 2 μg/ml), capreomycin (0.5 to 4 μg/ml), linezolid (0.25 to 2 μg/ml), and clofazimine (0.03 to 0.25 μg/ml). QC ranges could not be established for nicotinamide (pyrazinamide surrogate), prothionamide, or ethionamide, which were assay nonperformers. Using strict CLSI criteria, QC ranges against the M. tuberculosis H37Rv reference strain were established for the majority of commonly used antituberculosis drugs, with a convenient 7H9 broth microdilution MIC method suitable for use in resource-limited settings.
authors.affiliation: Janssen Research & Development, LLC, Titusville, New Jersey, USA kkaniga@its.jnj.com.
authors.forename: Koné
authors.initials: K
authors.lastname: Kaniga
authors.affiliation: IRCCS, San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Daniela M
authors.initials: DM
authors.lastname: Cirillo
authors.affiliation: TB Supranational Reference Laboratory, The Public Health Agency of Sweden, Solna, Sweden.
authors.forename: Sven
authors.initials: S
authors.lastname: Hoffner
authors.affiliation: National TB Reference Laboratory, Center for Tuberculosis, National Institute of Communicable Diseases, Johannesburg, South Africa.|Department of Medical Microbiology, University of Pretoria, Pretoria, South Africa.
authors.forename: Nazir A
authors.initials: NA
authors.lastname: Ismail
authors.affiliation: University of Massachusetts Medical School, Massachusetts Supranational TB Reference Laboratory, Boston, Massachusetts, USA.
authors.forename: Devinder
authors.initials: D
authors.lastname: Kaur
authors.affiliation: Janssen Pharmaceutica NV, Beerse, Belgium.
authors.forename: Nacer
authors.initials: N
authors.lastname: Lounis
authors.affiliation: Reference Laboratory, Division of TB Elimination, United States Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: Beverly
authors.initials: B
authors.lastname: Metchock
authors.affiliation: Department of Medical Microbiology, Center of Laboratory Medicine, Luzerner Kantonsspital LUKS, Luzern, Switzerland.
authors.forename: Gaby E
authors.initials: GE
authors.lastname: Pfyffer
authors.affiliation: TASK Applied Science, SA MRC Centre for TB Research, DST/NRF Center of Excellence for Biomedical TB Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa.
authors.forename: Amour
authors.initials: A
authors.lastname: Venter
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology*; D002991:Clofazimine / Q000494:pharmacology*; D024841:Fluoroquinolones / Q000494:pharmacology*; D006801:Humans; D000069349:Linezolid / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests / Q000379:methods*; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D011786:Quality Control; D018088:Tuberculosis, Multidrug-Resistant / Q000188:drug therapy* / Q000382:microbiology
chemical_list: D000995:Antitubercular Agents; D024841:Fluoroquinolones; D002991:Clofazimine; D000069349:Linezolid