title: Molecular characterization of class b carbapenemases in advanced stage of dissemination and emergence of class d carbapenemases in Enterobacteriaceae from Croatia.
abstract: Carbapenemases involved in acquired carbapenem resistance in Enterobacteriaceae belong to Ambler class A serin β-lactamases, class B metallo-β-lactamases (MBL) or class D OXA-48-like β-lactamases. The aim of the present study was to analyse the molecular epidemiology and the mechanisms and routes of spread of class B and class D carbapenemases in Croatia. In total 68 isolates were analyzed. Antibiotic susceptibility was determined by broth microdilution method. PCR was used to detect antibiotic-resistance genes. Genotyping was performed by rep-PCR and MLST. Sixty-five isolates were found to harbour VIM-1 carbapenemase, seven of which were positive also for NDM-1, while two strains harboured only NDM-1. OXA-48 was detected in three isolates, two of which coproduced VIM-1. Thirty-six strains possessed additional CTX-M-15 β-lactamase whereas 64 were positive for TEM-1. CMY was found in 18 Citrobacter freundii isolates and DHA-1 in one Enterobacter cloacae isolate. Four different plasmid-incompatibility groups were found: A/C, L/M, N and FIIAs. Unlike C. freundii and E. cloacae, Klebsiella pneumoniae showed high diversity of rep-PCR patterns. E. cloacae and C. freundii predominantly belonged to one large clone which was allocated to ST105 and ST24, respectively. Three different types of carbapenemases were identified showing the complexity of CRE in Croatia.
authors.affiliation: Department of Microbiology, School of Medicine, University of Zagreb, Salata 3b, 10000 Zagreb, Croatia; Department of Clinical and Molecular Microbiology, University Hospital Center Zagreb, Kispatic Street 12, 10000 Zagreb, Croatia. Electronic address: branka.bedenic@kbc-zagreb.hr.
authors.forename: Branka
authors.initials: B
authors.lastname: Bedenić
authors.affiliation: Department of Clinical Microbiology, University Hospital Center Split, Spincic Street 1, 21000 Split, Croatia. Electronic address: sandasard@gmail.com.
authors.forename: Sanda
authors.initials: S
authors.lastname: Sardelić
authors.affiliation: Institute for Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Universitatsplatz 4, 8010, Graz, Austria. Electronic address: josefa.luxner@medunigraz.at.
authors.forename: Josefa
authors.initials: J
authors.lastname: Luxner
authors.affiliation: Department of Microbiology, School of Medicine, University of Zagreb, Salata 3b, 10000 Zagreb, Croatia; Department of Clinical and Molecular Microbiology, University Hospital Center Zagreb, Kispatic Street 12, 10000 Zagreb, Croatia. Electronic address: zrinkabosnjak@gmail.com.
authors.forename: Zrinka
authors.initials: Z
authors.lastname: Bošnjak
authors.affiliation: Department of Clinical and Molecular Microbiology, University Hospital Center Zagreb, Kispatic Street 12, 10000 Zagreb, Croatia. Electronic address: dijanavb098@gmail.com.
authors.forename: Dijana
authors.initials: D
authors.lastname: Varda-Brkić
authors.affiliation: Department of Microbiology, School of Medicine, University of Zagreb, Children's Hospital Zagreb, Klaic Street 16, 10000 Zagreb, Croatia. Electronic address: amarela.lukic@kdb.hr.
authors.forename: Amarela
authors.initials: A
authors.lastname: Lukić-Grlić
authors.affiliation: Department of Microbiology, School of Medicine, University of Zagreb, Salata 3b, 10000 Zagreb, Croatia; Department of Clinical and Molecular Microbiology, University Hospital Center Zagreb, Kispatic Street 12, 10000 Zagreb, Croatia. Electronic address: imarekov@kbc-zagreb.hr.
authors.forename: Ivana
authors.initials: I
authors.lastname: Mareković
authors.affiliation: Public Health Center Zagreb, Laginja Street 16, 10000 Zagreb, Croatia. Electronic address: Sonja.francula@post.t-com.hr.
authors.forename: Sonja
authors.initials: S
authors.lastname: Frančula-Zaninović
authors.affiliation: Department of Microbiology, Public Health Institute of Dubrovnik-Neretva County, Ante Sercer Street 4a, 20000 Dubrovnik, Croatia. Electronic address: marija.krilanovic@gmail.com.
authors.forename: Marija
authors.initials: M
authors.lastname: Krilanović
authors.affiliation: School of Medicine, University of Zagreb, Salata 3b, 10000 Zagreb, Croatia. Electronic address: dora.peta@gmail.com.
authors.forename: Dorotea
authors.initials: D
authors.lastname: Šijak
authors.affiliation: Institute for Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Universitatsplatz 4, 8010, Graz, Austria. Electronic address: andrea.grisold@medunigraz.at.
authors.forename: Andrea
authors.initials: A
authors.lastname: Grisold
authors.affiliation: Institute for Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Universitatsplatz 4, 8010, Graz, Austria. Electronic address: gernot.zarfel@medunigraz.at.
authors.forename: Gernot
authors.initials: G
authors.lastname: Zarfel
mesh_terms: D015780:Carbapenems / Q000494:pharmacology*; D017523:Croatia; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology; D060005:Genotyping Techniques; D006801:Humans; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D010802:Phylogeny; D001618:beta-Lactamases / Q000145:classification* / Q000235:genetics
chemical_list: D015780:Carbapenems; C417264:VIM-1 metallo-beta-lactamase; C473109:beta-lactamase CTX-M-15; D001618:beta-Lactamases; C552864:beta-lactamase NDM-1
keywords: Carbapenems; Enterobacteriaceae; NDM-1; OXA-48; VIM-1