title: Pyrazinamide susceptibility testing: proposed new standard with the BACTECTM MGITTM 960 system.
abstract: The susceptibility of 253 Mycobacterium tuberculosis complex isolates to pyrazinamide (PZA) was assessed using the BACTECTM MGITTM 960 (M960) system. Resistant strains underwent paired repeat testing using 1) a critical concentration of 200 g/ml (PZA-200), and 2) a reduced inoculum of 0.25 ml. They were also examined using the BACTEC 460 (B460) reference method and investigated for pncA mutations. On M960, 37 isolates were resistant. In the PZA-200 assay, 20 of these were resistant and 17 susceptible, while 18 were resistant and 19 susceptible with reduced inoculum. The B460 assay and pncA sequencing confirmed results with reduced inoculum.
authors.affiliation: Regional Reference Mycobacteria Laboratory, United Hospitals, Ancona.
authors.forename: C
authors.initials: C
authors.lastname: Piersimoni
authors.affiliation: Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanit, Rome.
authors.forename: A
authors.initials: A
authors.lastname: Mustazzolu
authors.affiliation: Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanit, Rome.
authors.forename: A
authors.initials: A
authors.lastname: Iacobino
authors.affiliation: Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanit, Rome.
authors.forename: F
authors.initials: F
authors.lastname: Giannoni
authors.affiliation: Microbiology and Virology Laboratory, Dei Colli Hospital, Naples, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Santoro
authors.affiliation: Regional Reference Mycobacteria Laboratory, United Hospitals, Ancona.
authors.forename: G
authors.initials: G
authors.lastname: Gherardi
authors.affiliation: Microbiology and Virology Laboratory, Dei Colli Hospital, Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Del Giudice
authors.affiliation: Microbiology and Virology Laboratory, Dei Colli Hospital, Naples, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Perna
authors.affiliation: Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanit, Rome.
authors.forename: L
authors.initials: L
authors.lastname: Fattorini
mesh_terms: D000581:Amidohydrolases / Q000235:genetics; D000995:Antitubercular Agents / Q000627:therapeutic use*; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D006801:Humans; D008826:Microbial Sensitivity Tests; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics; D011718:Pyrazinamide / Q000627:therapeutic use*; D012680:Sensitivity and Specificity; D018088:Tuberculosis, Multidrug-Resistant / Q000188:drug therapy
chemical_list: D000995:Antitubercular Agents; D011718:Pyrazinamide; D000581:Amidohydrolases; C487496:PncA protein, Mycobacterium tuberculosis