Infection and Drug Resistance (Feb 2020)
Detection of Chromosomal and Plasmid-Mediated Quinolone Resistance Among Escherichia coli Isolated from Urinary Tract Infection Cases; Zagazig University Hospitals, Egypt
Abstract
Noura E Esmaeel, 1 Marian A Gerges, 1 Thoraya A Hosny, 2 Ahmed R Ali, 3 Manar G Gebriel 1 1Medical Microbiology and Immunology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt; 2Clinical Pathology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt; 3Urology Department, Faculty of Medicine, Zagazig University, Zagazig, EgyptCorrespondence: Marian A GergesMedical Microbiology and Immunology Department, Faculty of Medicine, Zagazig University, 44519, EgyptTel +20 1003819530Email [email protected]: Resistance to fluoroquinolones (FQ) in uropathogenic Escherichia coli (UPEC) has emerged as a growing problem. Chromosomal mutations and plasmid-mediated quinolone resistance (PMQR) determinants have been implicated. Data concerning the prevalence of these determinants in UPEC in our hospital are quite limited.Purpose: To investigate the occurrence and genetic determinants of FQ resistance in UPEC isolated from urinary tract infection (UTI) cases in Zagazig University Hospitals.Patients and Methods: Following their isolation, the identification and susceptibility of UPEC isolates were performed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometer (MALDI-TOF MS). FQ resistance was detected by the disc diffusion method. Ciprofloxacin minimal inhibitory concentration (MIC) was determined using E-test. Chromosomal mutations in the gyrA gene were detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and for detection of PMQR, a couple of multiplex PCR reactions were used.Results: Among a total of 192 UPEC isolates, 46.9% (n=90) were FQ resistant. More than half of the isolates (57.8%) exhibited high-level ciprofloxacin resistance (MIC > 32 μg/mL). Mutations in gyrA were detected in 76.7% of isolates, with 34.4% having mutations at more than one site. PMQR determinants were detected in 80.1% of UPEC isolates, with aac(6ʹ)-Ib-cr gene being the most frequent found in 61.1% of isolates.Conclusion: There is a high prevalence of both gyrA mutations and PMQR determinants among UPEC isolates in our hospital which contribute to high-level ciprofloxacin resistance, a finding that may require the revision of the antibiotics used for empirical treatment of UTI.Keywords: gyrA mutations, qnr determinants, uropathogenic E. coli, ciprofloxacin resistance
