title: Polyclonal spread and outbreaks with ESBL positive gentamicin resistant Klebsiella spp. in the region Kennemerland, The Netherlands.
abstract: OBJECTIVE
  The objective of this study was to analyze the transmission dynamics of ESBL positive Klebsiella spp. with an additional resistance towards gentamicin (ESBL-G) in a Dutch region of 650,000 inhabitants in 2012.
  
  
  METHODS
  All patient related ESBL-G isolates isolated in 2012 were genotyped using both Amplification Fragment Length Polymorphism (AFLP) and High-throughput MultiLocus Sequence Typing (HiMLST). HiMLST was used to analyze the presence of (unidentified) clusters of ESBL-G positive patients. Furthermore, all consecutive ESBL-G isolates within patients were studied in order to evaluate the intra-patient variation of antibiotic phenotypes.
  
  
  RESULTS
  There were 38 ESBL-G isolates, which were classified into 18 different sequence types (STs) and into 21 different AFLP types. Within the STs, four clusters were detected from which two were unknown resulting in a transmission index of 0.27. An analysis of consecutive ESBL-G isolates (with similar STs) within patients showed that for 68.8% of the patients at least one isolate had a different consecutive antibiotic phenotype.
  
  
  CONCLUSIONS
  The transmission of ESBL-G in the region Kennemerland in 2012 was polyclonal with several outbreaks (with a high level of epidemiological linkage). Furthermore, clustering by antibiotic phenotype characterization seems to be an inadequate approach in this setting. The routine practice of molecular typing of collected ESBL-G isolates may help to detect transmission in an early stage, which opens the possibility of a rapid response.
authors: Department of Epidemiology and Infection Prevention, Regional Public Health Laboratory Kennemerland, Haarlem, The Netherlands.
authors: Dennis
authors: D
authors: Souverein
authors: Department of Epidemiology and Infection Prevention, Regional Public Health Laboratory Kennemerland, Haarlem, The Netherlands.
authors: Stefan A
authors: SA
authors: Boers
authors: Department of Epidemiology and Infection Prevention, Regional Public Health Laboratory Kennemerland, Haarlem, The Netherlands.
authors: Dick
authors: D
authors: Veenendaal
authors: Department of Epidemiology and Infection Prevention, Regional Public Health Laboratory Kennemerland, Haarlem, The Netherlands.
authors: Sjoerd M
authors: SM
authors: Euser
authors: Laboratory for Microbiology and Infection Control, Amphia Hospital, Breda, and VU University Medical Center, Amsterdam, The Netherlands.
authors: Jan
authors: J
authors: Kluytmans
authors: Department of Epidemiology and Infection Prevention, Regional Public Health Laboratory Kennemerland, Haarlem, The Netherlands.
authors: Jeroen W
authors: JW
authors: Den Boer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001424:Bacterial Infections / Q000453:epidemiology* / Q000635:transmission; D004196:Disease Outbreaks / Q000706:statistics & numerical data; D024881:Drug Resistance, Bacterial; D005260:Female; D005839:Gentamicins / Q000494:pharmacology*; D006801:Humans; D007709:Klebsiella / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D012150:Polymorphism, Restriction Fragment Length
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins