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Treatment Failure in Urinary Tract Infections: A Warning Witness for Virulent Multi-Drug Resistant ESBL- Producing Escherichia coli

Authors Naziri Z, Derakhshandeh A, Soltani Borchaloee A, Poormaleknia M, Azimzadeh N

Received 2 April 2020

Accepted for publication 1 June 2020

Published 17 June 2020 Volume 2020:13 Pages 1839—1850


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 3

Editor who approved publication: Professor Suresh Antony

Zahra Naziri, Abdollah Derakhshandeh, Arash Soltani Borchaloee, Meisam Poormaleknia, Negar Azimzadeh

Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran

Correspondence: Zahra Naziri
Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz 71345– 1731 Tel +98 71 36138668
Fax +98 71 32286940

Background: Global increase in the prevalence of virulent extended-spectrum beta-lactamase (ESBL)-producing uropathogenic Escherichia coli (UPEC), which is also multi-drug resistant (MDR), leads to increase in severity of urinary tract infections (UTIs), decrease in the efficacy of the first-line antibiotics, and therefore increase in the morbidity and mortality rates.
Methods: We investigated the distribution of ESBL-producing UPEC in 78 E. coli isolates from community-acquired UTI patients in southern Iran. The prevalence of three major ESBL genes, antimicrobial resistance patterns against 15 conventional antibiotic disks, and the presence of 11 important virulence genes that involve in the development and progression of UTIs were evaluated in these isolates.
Results: Of the UPECs, 34.6% were ESBL-positive and 96.3% of the ESBL-producers were MDR. Among the ESBL-producers, 100% harbored blaCTX-M, 63% harbored blaSHV, and 11.1% harbored blaTEM genes. ESBL-producers showed a higher level of resistance to the tested cephalosporins, fluoroquinolones, trimethoprim-sulfamethoxazole, and tetracycline than non-ESBL producers. All isolates were resistant to the tested penicillins. Prevalence of resistance to about two-third of the tested antibiotics was higher than 50% and 93.6% of the isolates were MDR. High prevalence of virulence factors particularly the adhesins (82.1% csgA, 73.1% fimH genes) and siderophore (73.1% sitA gene) was seen in the UPECs. But fortunately in MDR isolates, the virulence score and prevalence of hemagglutinin (tsh), hemolysin toxin (hlyD) and invasin (ibeA) genes were lower than in non-MDR UPECs. Shockingly, among the 15 common antibiotics, only nitrofurantoin (< 20% resistance) could be recommended as an appropriate drug for the treatment of UTIs due to our ESBL-producer UPECs.
Conclusion: The alarming level of virulent MDR ESBL-producer E. coli strains in this study necessitates the performing of an antibiotic stewardship program, regional screening of ESBL-producers and their virulence properties to select appropriate antibiotic, or designing new therapeutic methods for UTIs by inactivation of the essential virulence factors of UPECs.

Keywords: uropathogenic Escherichia coli, extended spectrum beta-lactamases, multi-drug resistance, virulence factor, urinary tract infection

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