qnr Prevalence in Extended Spectrum Beta-lactamases (ESBLs) and None- ESBLs Producing Escherichia coli Isolated from Urinary Tract Infections in Central of Iran

Document Type: Original Article


1 Department Microbiology, Faculty of Medicine and Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran

2 Department Microbiology, Faculty of Medicine and Molecular Medicine Research Center, Arak University of Medical Sciences, Arak, Iran

3 Department Microbiology, Iranian Reference Health Laboratory, Tehran, Iran

4 Department Microbiology, Karaj Islamic Azad University, Karaj/Iran


Extensive use of quinolones has been associated with raising level of resistance. In the current, we focused on assessing the prevalence of Escherichia coli resistance to quinolones and frequency of qnrA, qnrB and qnrS in non ESBLs (extended spectrum beta-lactamases) and ESBLs producing E. coli with blaSHV and blaTEM.
Materials and Methods
One hundred and fifty E. coli isolates were identified during Mar. 2007 to Apr. 2008 in Milad (Tehran) hospital. They were tested for ESBLs production as well as quinolone resistance. PCR was performed for detection of blaSHV and blaTEM as well as qnrA, B and S.
Of 150 isolates, forty-two (28%) ESBLs producing and one hundred and eight (72%) non-ESBLs producing E. coli were identified. 64.2% (n= 24) of E. coli producing ESBLs and 4.62% (n= 5) of non-ESBLs E. coli were resistance to ciprofloxacin. 95.2% (n= 40) and 26.1% (n= 11) of the isolates harbored blaTEM and blaSHV, respectively. 23.8% (n= 10) had both genes. 37.5% (n= 9) and 20.8% (n= 4) of ESBLs producing E. coli were positive for qnrA and qnrB respectively. qnrS was not identified in any isolate.
Our study showed high frequency of ESBLs producing E. coli as well as quinolone resistance genes (qnrA, qnrB) in Milad hospital.


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