Background: urinary tract infections (UTIs) are one of the most common infectious diseases diagnosed all over the world. Meanwhile most episode of UTIs are caused by Escherichia coli (up to 85%) and frequently fluoroquinolones are preferred as initial agents for empiric therapy of UTIs. Widespread use of fluoroquinolones has resulted in an increasing incidence of resistance these agents all over the world. The aim of this study was to assess, susceptibility of Escherichia coli strains from UTI patients against common fluoroquinolones. Methods: Antimicrobial susceptibility testing was determined by disk agar diffusion (DAD) and Minimal Inhibitory Concentration methods as described by the National Committee for Clinical Laboratory Standards (NCCLS). Results: One hundred sixty four clinical isolates of E. coli were collected by urine cultures from patients with UTI. The extent of resistant to nalidixic acid, ofloxacin, norfloxacin and ciprofloxacin, by disk diffusion method was 49.3%, 44.5%, 41.4% and 40.2%, respectively. Resistance to ciprofloxacin by MIC method was 4.9%.Conclusion: This study represents high level resistant of E. coli isolates from UTI patients. It is because of inappropriate and incorrect administration of antimicrobial agents in blind cases. This problem remarks significance of performing antimicrobial susceptibility testing before empiric antibiotic therapy. To overcome this problem use of unnecessary antibiotics therapy should be limited.

The emergence of multidrug resistant strains of Escherichia coli has complicated treatment decision and may lead to treatment failures. From April to November 2001 we prospectively evaluated the prevalence of resistance to trimethoprim-sulfamethoxazole (SXT), gentamicin, cephalothin, ciprofloxacin, and nitrofurantoin in 220 Escherichia coli isolates from patients with urinary tract infections in kashan, Iran. To assess the current breadth of multidrug resistance among urinary isolates of E. coli. of total isolates, 10.9% were resistant to three or more agents and considered multidrug resistant. Among the multidrug resistant isolates, 91.7% were resistant to SXT, 75% to gentamicin, 58.3% to cephalothin, 54.2% to ciprofloxacin and 45.8% to nitrofurantoin. The predominant phenotype among multidrug resistant isolates (29.2%) included resistance to SXT, gentamicin, and cephalothin. Rates of multidrug resistance were demonstrated to be higher among males (13.2%) than females (10.4%). There was no significant association between gender and reduced susceptibility. Continued local surveillance studies are urged to monitor emerging antimicrobial resistance and to guide interventions to minimize its occurrence.

Background: urinary tract infections (UTIs) with non-Escherichia coli (E. coli) species are associate with urological abnormalities. Objectives: To compare the prevalence of non-E. coli infections in patients with urological anomalies, neurogenic bladder dysfunction, and those with apparently normal urinary systems. Methods: Pediatric nephrology clinic at a tertiary-care center in east of Iran. Children affected by UTI enrolled from 2003 to 2016. The results of urine culture were noted at enrolment. Cases with nephrolithiasis who had normal voiding cystourethrogram were excluded. After the implementation of imaging and urodynamic examinations, 832 patients enrolled according to the following inclusion criteria: cases with vesicoureteral reflux, urinary obstruction, neurogenic bladder, and patients with apparently normal urinary tract. The prevalence of infections with E. coli vs. non-E. coli pathogens were compared between different groups of enrolled cases. Results: In this study, 62. 26% of the subjects had a normal urinary system, while 33. 77%, 3. 97%, and 2. 4% of whom had vesicoureteral reflux, neurogenic bladder, and obstruction, respectively. Non-E. coli pathogens were responsible for infections in 17. 29%, 19. 39%, 33. 74%, and 17. 15% of these cases, respectively. infections with non-E. coli pathogens were significantly more prevalent in cases with neurogenic bladder (P = 0. 003). Pseudomonas species were responsible for 4/125, 5/118, 5/28, and 0/6 episodes of non-E. coli infections in cases with apparently normal urinary system, patients with vesicoureteral reflux, cases with neurogenic bladder, and those with urinary obstruction, respectively (P = 0. 004). Conclusions: infections with non-E. coli and also Pseudomonas species are significantly more prevalent in patients with neurogenic bladder dysfunction rather than those with urological abnormalities and/or cases with apparently normal urinary system.

Introduction. Escherichia coli are the most frequent pathogens in acute urinary infections. They are classified based on various types of O antigen.Escherichia coli strains that cause urinary tract infections possess several genes encoding urovirulent factors. To assay the relation of virulent factors ofE coli in acute urinary infections, the serotypes and virulence factor genotypes were determined.Materials and Methods. We studied 96 E coli isolates from children with acute urinary infections. Four urovirulence determinants were analyzed by DNA colony hybridization, including the genes for type 1 fimbriae (pil), P fimbriae (pap), S fimbriae (sfa), hemolysin (hly), and cytotoxic necrotizing factor 1 (cnf1). O serotypes were also determined.Results. The most frequently found virulence factor-encoding gene in theE coli strains studied was the gene for type 1 fimbriae (27.4%).The prevalence ofpap, sfa, hly, and cnf1 were higher in serotypes causing pyelonephritis than cystitis. The most common type of O antigen was O1 (12.2%). There was a significant correlation between serotype and genotype in uropathogenicE coli.Conclusions. The high prevalence of O6 serotypes in children urinary tract infections and the high percentage of virulent genes in serotype O6 suggested a close relation between serotype and genotypes of uropathogenE coli.