title: Prevalence of Quinolone Resistance Genes Among Extended-Spectrum B-Lactamase-Producing Escherichia coli in Mashhad, Iran.
abstract: BACKGROUND
  Escherichia coli is an important bacterial species based on incidence and associated infection severity. Some E. coli strains produce extended-spectrum beta lactamase (ESBL) and are called ESBL-producing E. coli. These strains are resistant to most classes of cephalosporin and a number of other classes of antibiotics. Plasmids carrying qnr genes have been found to transmit quinolone resistance.
  
  
  OBJECTIVE
  The aim of this study was to determine the frequency of qnr genes in ESBL-producing and non-ESBL-producing E. coli isolated from outpatient and hospitalized patient clinical specimens from Imam Reza hospital in Mashhad, Iran.
  
  
  METHODS
  Two hundred E. coli strains, isolated from different clinical specimens were used. ESBL-producing E. coli were detected by determining susceptibility to ceftazidime, cefotaxime, and cefpodoxime with the phenotypic confirmatory test (PCT). PCR analysis was employed to detect the qnrA, qnrB, qnrS, bla TEM , and bla SHV genes.
  
  
  RESULTS
  Eighty-six (43%) isolates were ciprofloxacin-resistant. The PCT identified 85 (42.5%) of 200 E. coli isolates as ESBL-producing. The bla TEM , bla SHV , qnrA, qnrB, and qnrS gene were found in 65 (76.47%), 23 (27%), 63 (31%), 34 (17%), and 14 (7%) isolates, respectively.
  
  
  CONCLUSIONS
  The high prevalence of quinolone resistance genes, which indicates antibiotic resistance, in the Imam Reza Hospital of Mashhad is a major concern. Hence, the antibiotics prescription policy should be revised, and infection control measures should be improved.
authors: Student Research Committee (SRC), Mashhad University of Medical Sciences, Mashhad, IR Iran; Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Elnaz
authors: E
authors: Harifi Mood
authors: Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Zahra
authors: Z
authors: Meshkat
authors: Student Research Committee (SRC), Mashhad University of Medical Sciences, Mashhad, IR Iran; Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Nafiseh
authors: N
authors: Izadi
authors: Department of Microbiology and Immunology, Faculty of Medicine, Kashan University of Medical Sciences, Kashan, IR Iran.
authors: Maryam
authors: M
authors: Rezaei
authors: Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Saeid
authors: S
authors: Amel Jamehdar
authors: Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Mahboubeh
authors: M
authors: Naderi Nasab
keywords: Escherichia coli; Extended-Spectrum Beta-Lactamas; Quinolone Resistance