title: KPC-Producing Klebsiella pneumoniae Isolates in Croatia: A Nationwide Survey.
abstract: BACKGROUND
  In the last few years, Klebsiella pneumoniae strains producing K. pneumoniae carbapenemase (KPC) enzymes have emerged as important multidrug-resistant pathogens in hospitalized patients. This report describes KPC-producing isolates collected through the Croatian antimicrobial resistance surveillance program in the early stage of their dissemination in Croatia.
  
  
  METHODS
  Forty-eight KPC-producing K. pneumoniae isolates, collected during a period from February 2011 to August 2013, were analyzed in this study. Antimicrobial susceptibility profiles were determined using disk diffusion and E-test. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used for epidemiological analysis. Identification of β-lactamase genes and associated antibiotic resistance mechanisms was performed by polymerase chain reaction and positive products were sequenced. Localization of blaKPCwas investigated by S1 PFGE and Southern hybridization.
  
  
  RESULTS
  Of 40 participating centers in Croatia, KPC isolates were recorded in 9 of them. They all had multidrug-resistant phenotype, but showed varying levels of resistance to carbapenems. All isolates displayed ST258, and PFGE showed that all but one were closely related. All isolates harbored blaKPC-2. Isolate with a unique PFGE pattern produced TEM-1, while others produced TEM-116. All isolates harbored blaSHV-11, but were negative for blaCTX-Mand blaAmpCgenes. All isolates contain one KPC-harboring plasmid, ranging in size from ∼60 to ∼210 kb, characterized as FIIs and IncR.
  
  
  CONCLUSIONS
  This report describes that the early stage of KPC-producing K. pneumoniae dissemination in Croatia is associated with a prolific PFGE type belonging to ST258. So far, the spread of an outbreak strain is limited to the northwest region of the country.
authors.affiliation: 1 Department of Clinical Microbiology, University Hospital for Infectious Diseases , Zagreb, Croatia .
authors.forename: Marko
authors.initials: M
authors.lastname: Jelic
authors.affiliation: 1 Department of Clinical Microbiology, University Hospital for Infectious Diseases , Zagreb, Croatia .
authors.forename: Iva
authors.initials: I
authors.lastname: Butic
authors.affiliation: 2 Microbiology Department, University Hospitals Morecambe Trust , Lancaster, United Kingdom .
authors.forename: Vanda
authors.initials: V
authors.lastname: Plecko
authors.affiliation: 3 Department of Clinical Microbiology, Institute of Public Health County Krapinsko-Zagorska , Zabok, Croatia .
authors.forename: Ivan
authors.initials: I
authors.lastname: Cipris
authors.affiliation: 4 Department of Microbiology, Parasitology and Hospital Infections, Clinical Hospital Center "Sestre milosrdnice ," Zagreb, Croatia .
authors.forename: Ines
authors.initials: I
authors.lastname: Jajic
authors.affiliation: 5 Department of Clinical Microbiology and Hospital Infections, Clinical Hospital "Sveti Duh ," Zagreb, Croatia .
authors.forename: Danijela
authors.initials: D
authors.lastname: Bejuk
authors.affiliation: 6 Department of Medical Microbiology, Public Health Institute of County Varazdin , Varazdin, Croatia .
authors.forename: Iva
authors.initials: I
authors.lastname: Koscak
authors.affiliation: 7 Department of Clinical and Molecular Microbiology, Clinical Hospital Center Zagreb , Zagreb, Croatia .
authors.forename: Sonja
authors.initials: S
authors.lastname: Marinkovic
authors.affiliation: 8 Microbiology Laboratory, Institute of Public Health County Međimurje , Čakovec, Croatia .
authors.forename: Marina Payerl
authors.initials: MP
authors.lastname: Pal
authors.affiliation: 1 Department of Clinical Microbiology, University Hospital for Infectious Diseases , Zagreb, Croatia .
authors.forename: Arjana Tambic
authors.initials: AT
authors.lastname: Andrasevic
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D015780:Carbapenems / Q000494:pharmacology; D017523:Croatia / Q000453:epidemiology; D004269:DNA, Bacterial / Q000235:genetics; D052978:Disk Diffusion Antimicrobial Tests; D016521:Electrophoresis, Gel, Pulsed-Field; D015964:Gene Expression Regulation, Bacterial; D006306:Health Surveys; D006801:Humans; D015994:Incidence; D007710:Klebsiella Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification; D017720:Molecular Epidemiology; D058885:Multilocus Sequence Typing; D010957:Plasmids / Q000737:chemistry / Q000145:classification / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D018440:beta-Lactam Resistance / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D004269:DNA, Bacterial; D001618:beta-Lactamases; C063912:carbapenemase
keywords: Croatia; KPC; Klebsiella pneumoniae; ST258