Antimicrobial susceptibility of uropathogenic Escherichia coli strains

Abstract

Introduction: Urinary tract infections (UTIs) are some of the most common infections experienced by humans, exceeded in frequency among ambulatory patients only by respiratory and gastrointestinal infections. The vast majority of uncomplicated UTIs are caused by the Gram ­ negative bacillus Escherichia coli, with other pathogens including Enterococci, Staphylococcus saprophyticus, Klebsiella spp. and Proteus mirabilis. The extensive and inappropriate use of antimicrobial agents has invariably resulted in the development of antibiotic resistance which, in recent years, has become a major problem worldwide. In patients with suspected UTI, antibiotic treatment is usually started empirically, before urine culture results are available. To ensure appropriate treatment, knowledge of the organisms that cause UTI and their antibiotic susceptibility is mandatory. Occurrence and susceptibility profiles of E. coli show substantial geographic variations as well as significant differences in various populations and environments. Objectives: The aim of this study was to determine the prevalence and antimicrobial susceptibility of E. coli from clinical samples. Materials and Methods: Between 2010 and 2013, a total of 1916 samples from hospitalized patients in Republican Clinical Hospital were analyzed for isolation and identification of bacteria and antimicrobial susceptibility testing. E. coli was isolated from 542 (42.7%) samples. Bacterial isolates were identified by standard biochemical tests. Antibacterial susceptibility test was performed by the disc diffusion method was performed according to NCCLS (National Committee for Clinical Laboratory Standards). Results: E. coli was isolated from 542 (42.7%) samples. High resistance rates to cefazolin (87.5 %), ampicillin (52.0%), cefepime (62.0%), moxifloxacin (68.0%) were documented. However, significantly high degree of sensitivity rates to netilmicin (90.0%), norflaxocin (82.9% ), imipenem (93.0%), meropenem (90.0%), chloramphenicol (95,2%). Conclusions: Escherichia coli is the leading cause of urinary tract infections in humans. A rise in bacterial resistance to antibiotics complicates treatment of infections. The results of this study show high rates of antimicrobial resistance to cefazolin, ampicillin, cefepime, moxifloxacin. High degree of sensitivity rates to netilmicin (90.0%), norflaxocin (82.9%), imipenem (93.0% ), meropenem (90.0%), chloramphenicol. Periodic monitoring of antimicrobial susceptibility both in the community and hospital settings is recommended.