title: Performance of a MALDI-TOF MS-based imipenem hydrolysis assay incorporating zinc sulfate.
abstract: A MALDI-TOF MS1-based imipenem hydrolysis assay was modified by adding ZnSO4. This improved detection of metallo-β-lactamase producing strains without compromising detection of other carbapenemase types. Using 129 genetically characterized Gram-negative bacilli, the sensitivity and specificity were 98.5% (95% confidence interval [CI]: 91.9-99.7%) and 100% (95% CI: 94.3-100%), respectively.
authors.affiliation: Department of Chemistry and Biotechnology, Faculty of Science, Engineering and Technology, Swinburne University of Technology, John St, Hawthorn, Melbourne, 3122, Australia; Department of Microbiology, Melbourne Pathology, 103 Victoria Pde, Collingwood, Melbourne, 3066, Australia. Electronic address: jaknox2@yahoo.com.au.
authors.forename: James
authors.initials: J
authors.lastname: Knox
authors.affiliation: Department of Chemistry and Biotechnology, Faculty of Science, Engineering and Technology, Swinburne University of Technology, John St, Hawthorn, Melbourne, 3122, Australia. Electronic address: epalombo@swin.edu.au.
authors.forename: Enzo
authors.initials: E
authors.lastname: Palombo
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism*; D001426:Bacterial Proteins / Q000032:analysis / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004755:Enterobacteriaceae / Q000187:drug effects / Q000235:genetics*; D006801:Humans; D006868:Hydrolysis; D015378:Imipenem / Q000378:metabolism*; D008826:Microbial Sensitivity Tests; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D019287:Zinc Sulfate / Q000737:chemistry*; D001618:beta-Lactamases / Q000032:analysis / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015378:Imipenem; D019287:Zinc Sulfate; D001618:beta-Lactamases; C063912:carbapenemase
keywords: Carbapenemase; Enterobacteriaceae; Gram-negative; MALDI-TOF MS; Metallo-beta-lactamase; Zinc