title: Epidemiology of extended-spectrum beta-lactamase-producing Enterobacteriaceae in a UK district hospital; an observational study.
abstract: BACKGROUND
  Extended-spectrum beta-lactamases (ESBLs) are an increasingly important cause of resistance in Gram-negative bacteria throughout the world.
  
  
  OBJECTIVE
  We investigated the clinical and molecular epidemiology of infections caused by ESBL-producing Enterobacteriaceae in a UK hospital, to identify the types of ESBL produced and risk factors for acquisition.
  
  
  METHODS
  Between July 2008 and June 2009, all patients yielding ESBL-producing Enterobacteriaceae from any clinical specimen were prospectively investigated using a questionnaire. API20E was used for bacterial identification; susceptibility testing and ESBL production were assessed by BSAC disc diffusion and cefpodoxime-clavulanate synergy tests, respectively. Polymerase chain reaction was used to screen a subset of isolates for bla(CTX-M) genes, to assign Escherichia coli isolates to their phylogenetic groups, and to identify members of the uropathogenic ST131 lineage.
  
  
  RESULTS
  The overall prevalence of ESBL producers among clinical samples yielding Enterobacteriaceae was 1%; ESBL producers, obtained from 124 patients, were E. coli (N = 105), Klebsiella pneumoniae (N = 12), and others (N = 7). The main risk factors identified include recent antibiotic use (93%) and presence of a urinary catheter (24%). CTX-M group 1 ESBLs dominated (in 59 of 78, 76%, isolates studied). Most E. coli (35 of 56 tested) were phylogroup B2; of these, 23 belonged to the ST131 clone, 12 were phylogroup D, and four each belonged to phylogroups A and B1.
  
  
  CONCLUSIONS
  ESBLs are an uncommon but significant problem in north-west Cambridgeshire. CTX-M-type enzymes were found in 75% of ESBL-positive isolates. All but two patients had at least one recognized risk factor. This study supports the requirement for interventions to reduce inappropriate urinary catheterization and antibiotic prescribing.
authors: Clinical Microbiology & Public Health Laboratory, Peterborough & Stamford Hospitals NHS Foundation Trust, Peterborough City Hospital, Bretton Gate, Peterborough, UK. david.enoch@pbh-tr.nhs.uk
authors: D A
authors: DA
authors: Enoch
authors: F
authors: F
authors: Brown
authors: A W
authors: AW
authors: Sismey
authors: D A
authors: DA
authors: Mlangeni
authors: M D
authors: MD
authors: Curran
authors: J A
authors: JA
authors: Karas
authors: D B
authors: DB
authors: Cone
authors: S H
authors: SH
authors: Aliyu
authors: H
authors: H
authors: Dhanji
authors: M
authors: M
authors: Doumith
authors: S
authors: S
authors: Maharjan
authors: D
authors: D
authors: Meunier
authors: N
authors: N
authors: Woodford
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000235:genetics; D004755:Enterobacteriaceae / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D005838:Genotype; D006767:Hospitals, District; D006801:Humans; D007223:Infant; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D058889:Molecular Typing; D016133:Polymerase Chain Reaction; D015995:Prevalence; D011795:Surveys and Questionnaires; D006113:United Kingdom / Q000453:epidemiology; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D004269:DNA, Bacterial; D001618:beta-Lactamases