title: Imipenem-avibactam: a novel combination for the rapid detection of carbapenemase activity in Enterobacteriaceae and Acinetobacter baumannii by matrix-assisted laser desorption ionization-time of flight mass spectrometry.
abstract: In the present study, we propose a novel matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS)-based method for detecting carbapenemase-producing Enterobacteriaceae and Acinetobacter baumannii. For this, we analyzed a series of 131 isolates. Among them, a total of 115 Enterobacteriaceae: 79 of them carrying a carbapenemase enzyme (15blaKPC, 7blaNDM, 11blaIMP, 12blaVIM, and 34blaOXA-48) and 16 A. baumannii isolates: 15 of them carrying carbapenemases (10blaOXA-23,2blaOXA-58,2blaOXA-24, and 1blaOXA-237). The rest of the isolates were noncarbapenemase producers and used as negative controls. The isolates were submitted to susceptibility testing using a combination of imipenem-avibactam and analysis by the MALDI-TOF Biotyper Compass software (Bruker Daltonik, Germany). The assay showed an overall sensitivity and specificity for carbapenemase detection of 98% and 100%, respectively. The combination of imipenem and avibactam displayed activity against KPC and OXA-48-producing Enterobacteriaceae and thus represents a new strategy for identifying and confirming these carbapenemases. However, the combination did not provide any benefit over A. baumannii.
authors.affiliation: Servicio de Microbiología, Complejo Hospitalario Universitario A Coruña, As Xubias s/n, 15006, La Coruña, Spain.
authors.forename: Marina
authors.initials: M
authors.lastname: Oviaño
authors.affiliation: Servicio de Microbiología, Complejo Hospitalario Universitario A Coruña, As Xubias s/n, 15006, La Coruña, Spain. Electronic address: german.bou.arevalo@sergas.es.
authors.forename: Germán
authors.initials: G
authors.lastname: Bou
mesh_terms: D040981:Acinetobacter baumannii / Q000187:drug effects / Q000201:enzymology*; D000900:Anti-Bacterial Agents / Q000378:metabolism*; D053961:Azabicyclo Compounds / Q000378:metabolism*; D001426:Bacterial Proteins / Q000032:analysis*; D004755:Enterobacteriaceae / Q000187:drug effects / Q000201:enzymology*; D015378:Imipenem / Q000378:metabolism*; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013997:Time Factors; D001618:beta-Lactamases / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D053961:Azabicyclo Compounds; D001426:Bacterial Proteins; D015378:Imipenem; C543519:avibactam; D001618:beta-Lactamases; C063912:carbapenemase
keywords: Antimicrobial resistance detection; Avibactam; Imipenem; MALDI-TOF