title: Escherichia coli sequence type 131 is a dominant, antimicrobial-resistant clonal group associated with healthcare and elderly hosts.
abstract: OBJECTIVE
  To determine prevalence, predictors, and outcomes of infection due to Escherichia coli sequence type ST131.
  
  
  METHODS
  Retrospective cohort.
  
  
  METHODS
  All healthcare settings in Olmsted County, Minnesota (eg, community hospital, tertiary care center, long-term care facilities, and ambulatory clinics).
  
  
  METHODS
  Ambulatory and hospitalized children and adults with extraintestinal E. coli isolates.
  
  
  METHODS
  We analyzed 299 consecutive, nonduplicate extraintestinal E. coli isolates submitted to Olmsted County laboratories in February and March 2011. ST131 was identified using single-nucleotide polymorphism polymerase chain reaction and further evaluated through pulsed-field gel electrophoresis. Associated clinical data were abstracted through medical record review.
  
  
  RESULTS
  Most isolates were from urine specimens (90%), outpatients (68%), and community-associated infections (61%). ST131 accounted for 27% of isolates overall and for a larger proportion of those isolates resistant to fluoroquinolones (81%), trimethoprim-sulfamethoxazole (42%), gentamicin (79%), and ceftriaxone (50%). The prevalence of ST131 increased with age (accounting for 5% of isolates from those 11-20 years of age, 26% of isolates from those 51-60 years of age, and 50% of isolates from those 91-100 years of age). ST131 accounted for a greater proportion of healthcare-associated isolates (49%) than community-associated isolates (15%) and for fully 76% of E. coli isolates from long-term care facility (LTCF) residents. Multivariable predictors of ST131 carriage included older age, LTCF residence, previous urinary tract infection, high-complexity infection, and previous use of fluoroquinolones, macrolides, and extended-spectrum cephalosporins. With multivariable adjustment, ST131-associated infection outcomes included receipt of more than 1 antibiotic (odds ratio [OR], 2.54 [95% confidence interval (CI), 1.25-5.17]) and persistent or recurrent symptoms (OR, 2.53 [95% CI, 1.08-5.96]). Two globally predominant ST131 pulsotypes accounted for 45% of ST131 isolates.
  
  
  CONCLUSIONS
  ST131 is a dominant, antimicrobial-resistant clonal group associated with healthcare settings, elderly hosts, and persistent or recurrent symptoms.
authors: Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN 55905, USA. banerjee.ritu@mayo.edu
authors: Ritu
authors: R
authors: Banerjee
authors: Brian
authors: B
authors: Johnston
authors: Christine
authors: C
authors: Lohse
authors: Stephen B
authors: SB
authors: Porter
authors: Connie
authors: C
authors: Clabots
authors: James R
authors: JR
authors: Johnson
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology; D003428:Cross Infection / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology; D004269:DNA, Bacterial / Q000032:analysis; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000145:classification* / Q000187:drug effects / Q000235:genetics; D004927:Escherichia coli Infections / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016015:Logistic Models; D008297:Male; D008826:Microbial Sensitivity Tests; D008910:Minnesota / Q000453:epidemiology; D015999:Multivariate Analysis; D016133:Polymerase Chain Reaction; D015995:Prevalence; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial