title: The impact of antibiotic use on the incidence and resistance pattern of extended-spectrum beta-lactamase-producing bacteria in primary and secondary healthcare settings.
abstract: BACKGROUND
  • The emergence and spread of bacteria producing extended-spectrum beta-lactamases (ESBLs) has important therapeutic and epidemiologic implications. • A key target for the establishment of hospital antibiotic stewardship is reducing the occurrence of additional antibiotic resistance. • Further research is needed to accumulate supporting evidence that reducing antibiotic use will result in a parallel reduction in antibiotic resistance.
  
  
  CONCLUSIONS
  • Fluoroquinolone restriction reversed ciprofloxacin resistance in primary and secondary healthcare settings. • Fluoroquinolone restriction reduced ESBL-producing bacteria incidence rates in both the primary and secondary healthcare settings. • This study highlights the value of time-series analysis in designing efficient antibiotic stewardship.
  
  
  OBJECTIVE
  The objective of the present study was to study the relationship between hospital antibiotic use, community antibiotic use and the incidence of extended-spectrum beta-lactamase (ESBL)-producing bacteria in hospitals, while assessing the impact of a fluoroquinolone restriction policy on ESBL-producing bacteria incidence rates.
  
  
  METHODS
  The study was retrospective and ecological in design. A multivariate autoregressive integrated moving average (ARIMA) model was built to relate antibiotic use to ESB-producing bacteria incidence rates and resistance patterns over a 5 year period (January 2005-December 2009).
  
  
  RESULTS
  Analysis showed that the hospital incidence of ESBLs had a positive relationship with the use of fluoroquinolones in the hospital (coefficient = 0.174, P= 0.02), amoxicillin-clavulanic acid in the community (coefficient = 1.03, P= 0.03) and mean co-morbidity scores for hospitalized patients (coefficient = 2.15, P= 0.03) with various time lags. The fluoroquinolone restriction policy was implemented successfully with the mean use of fluoroquinolones (mainly ciprofloxacin) being reduced from 133 to 17 defined daily doses (DDDs)/1000 bed days (P < 0.001) and from 0.65 to 0.54 DDDs/1000 inhabitants/day (P= 0.0007), in both the hospital and its surrounding community, respectively. This was associated with an improved ciprofloxacin susceptibility in both settings [ciprofloxacin susceptibility being improved from 16% to 28% in the community (P < 0.001)] and with a statistically significant reduction in ESBL-producing bacteria incidence rates.
  
  
  CONCLUSIONS
  This study supports the value of restricting the use of certain antimicrobial classes to control ESBL, and demonstrates the feasibility of reversing resistance patterns post successful antibiotic restriction. The study also highlights the potential value of the time-series analysis in designing efficient antibiotic stewardship.
authors.affiliation: Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, BT9 7BL Belfast, Northern Ireland, UK. maldeyab02@qub.ac.uk
authors.forename: Mamoon A
authors.initials: MA
authors.lastname: Aldeyab
authors.forename: Stephan
authors.initials: S
authors.lastname: Harbarth
authors.forename: Nathalie
authors.initials: N
authors.lastname: Vernaz
authors.forename: Mary P
authors.initials: MP
authors.lastname: Kearney
authors.forename: Michael G
authors.initials: MG
authors.lastname: Scott
authors.forename: Feras W
authors.initials: FW
authors.lastname: Darwish Elhajji
authors.forename: Motasem A
authors.initials: MA
authors.lastname: Aldiab
authors.forename: James C
authors.initials: JC
authors.lastname: McElnay
mesh_terms: D019980:Amoxicillin-Potassium Clavulanate Combination / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001419:Bacteria / Q000187:drug effects*; D003428:Cross Infection / Q000382:microbiology / Q000517:prevention & control*; D004202:Disinfectants / Q000627:therapeutic use*; D024841:Fluoroquinolones / Q000627:therapeutic use; D006761:Hospitals; D006801:Humans; D015994:Incidence; D015999:Multivariate Analysis; D011320:Primary Health Care; D012044:Regression Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D018440:beta-Lactam Resistance / Q000187:drug effects*; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D004202:Disinfectants; D024841:Fluoroquinolones; D065093:beta-Lactamase Inhibitors; D019980:Amoxicillin-Potassium Clavulanate Combination; D001618:beta-Lactamases