Ciprofloxacin resistance in uropathogenic Escherichia coli isolates causing community-acquired urinary infections in Brasília, Brazil

Abstract Objectives Considering the global concern of ciprofloxacin resistance, the aim of this study was to evaluate the characteristics of ciprofloxacin-resistant (CIP-R) Escherichia coli isolated from patients with community-acquired urinary tract infections (UTIs) in Brasilia, Brazil. Methods CIP-R E. coli isolated from different outpatients between July 2013 and April 2014 in a tertiary hospital were analysed for antibiotic resistance profile, phylotype, uropathogenic E. coli (UPEC) virulence genes, clonal relationship by enterobacterial repetitive intergenic consensus PCR (ERIC-PCR), and multilocus sequence typing (MLST). Results Among the 324 UPEC analysed, 263 (81.2%) were ciprofloxacin-sensitive and 61 (18.8%) were CIP-R. Antibiogram analysis of the 61 CIP-R strains showed that 45 (73.8%) were also multidrug-resistant. The most prevalent phylogroups were A and B2 (26/61 and 18/61, respectively). traT (53/61) and aer – traT (24/61) were the most common gene and genotype observed. Dendrogram analysis found that multidrug resistance and virulence genes were distributed among CIP-R strains independently of clonality and phylogroup. Six ERIC clusters (strains sharing ≥85% genetic similarity) were observed. MLST analysis of all strains of each cluster identified sequence types (STs) associated with worldwide antimicrobial resistance dissemination, including B2-ST131 and ST410, as well as STs not yet associated with antimicrobial resistance propagation, such as ST1725 and ST179. Conclusions These results demonstrate that ciprofloxacin resistance dissemination by UPEC causing community-acquired UTIs was associated with multidrug resistance and was promoted by pandemic and non-pandemic STs, a concerning scenario for the local population.