title: Prevalence and risk factors for carriage of ESBL-producing Enterobacteriaceae in Amsterdam.
abstract: OBJECTIVE
  The objectives of this study were to determine the prevalence of carriage of ESBL-producing Enterobacteriaceae (ESBL-E) in a representative sample of the general adult Dutch community, to identify risk factors and to gain understanding of the epidemiology of these resistant strains.
  
  
  METHODS
  Adults enrolled in five general practices in Amsterdam were approached by postal mail and asked to fill in a questionnaire and to collect a faecal sample. Samples were analysed for the presence of ESBL-E. ESBL genes were characterized by PCR and sequencing. Strains were typed using MLST and amplified fragment length polymorphism (AFLP) and plasmids were identified by PCR-based replicon typing. Risk factors for carriage were investigated by multivariate analysis.
  
  
  RESULTS
  ESBL-E were found in 145/1695 (8.6%) samples; 91% were Escherichia coli. Most ESBL genes were of the CTX-M group (blaCTX-M-1 and blaCTX-M-15). MLST ST131 was predominant and mainly associated with CTX-M-15-producing E. coli. One isolate with reduced susceptibility to ertapenem produced OXA-48. In multivariate analyses, use of antimicrobial agents, use of antacids and travel to Africa, Asia and Northern America were associated with carriage of ESBL-E, in particular strains with blaCTX-M-14/15.
  
  
  CONCLUSIONS
  This study showed a high prevalence of ESBL-E carriage in the general Dutch community. Also, outside hospitals, the use of antibiotics was a risk factor; interestingly, use of antacids increased the risk of carriage. A major risk factor in the general population was travel to countries outside Europe, in particular to Asia, Africa and Northern America.
authors.affiliation: Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands e.reuland@vumc.nl.
authors.forename: E A
authors.initials: EA
authors.lastname: Reuland
authors.affiliation: Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands Laboratory for Medical Microbiology and Public Health, Hengelo, The Netherlands Medical Microbiology and Infection Control, Ziekenhuisgroep Twente, Almelo, The Netherlands.
authors.forename: N
authors.initials: N
authors.lastname: Al Naiemi
authors.affiliation: Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: A M
authors.initials: AM
authors.lastname: Kaiser
authors.affiliation: Center for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Heck
authors.affiliation: Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands Department of Medical Microbiology and Infection Control, Amphia Hospital, Breda, The Netherlands Department of Medical Microbiology, St Elisabeth Hospital, Tilburg, The Netherlands.
authors.forename: J A J W
authors.initials: JA
authors.lastname: Kluytmans
authors.affiliation: Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: P H M
authors.initials: PH
authors.lastname: Savelkoul
authors.affiliation: EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: P J M
authors.initials: PJ
authors.lastname: Elders
authors.affiliation: Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: C M J E
authors.initials: CM
authors.lastname: Vandenbroucke-Grauls
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D054458:Amplified Fragment Length Polymorphism Analysis; D002353:Carrier State; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004755:Enterobacteriaceae / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D009426:Netherlands / Q000453:epidemiology; D011159:Population Surveillance; D015995:Prevalence; D012307:Risk Factors; D055815:Young Adult; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D001618:beta-Lactamases