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

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 Brasília, Brazil. 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). 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. 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.

Moreira da Silva RCR ，de Oliveira Martins Júnior P ，Gonçalves LF ，de Paulo Martins V ，de Melo ABF ，Pitondo-Silva A ，de Campos TA ... -  《-》

Multidrug resistance dissemination by extended-spectrum β-lactamase-producing Escherichia coli causing community-acquired urinary tract infection in the Central-Western Region, Brazil.

The aim of this work was to analyse extended-spectrum β-lactamase (ESBL)-producing Escherichia coli strains isolated from outpatients with signs of cystitis in Hospital Universitário de Brasília (Brasília, Brazil) during the period July 2013 to April 2014. E. coli isolated from urine culture were identified and their antibiotic susceptibility profile was determined by VITEK 2. ESBL-producing strains identified were submitted to PCR for Clermont phylotyping, CTX-M group typing and virulence determinant detection, and clonal relationships were determined by enterobacterial repetitive intergenic consensus (ERIC)-PCR. One strain belonging to each cluster of the dendrogram obtained by ERIC-PCR was selected for multilocus sequence typing (MLST). Among 324 uropathogenic E. coli (UPEC) analysed, 23 (7.1%) were identified as producing ESBL. All ESBL-producing strains were multidrug-resistant (MDR), i.e. presented non-susceptibility to at least one agent in three or more antimicrobial categories. Of the 23 ESBL-producing UPEC strains, 9 were assigned to phylogenetic group B2 and 7 each belonged to phylogenetic groups D and A. Virulence genotyping showed that aer was the most prevalent gene observed among the strains (21/23), followed by traT (18/23), pap (5/23), afa (5/23), PAI (5/23), cnf (3/23) and sfa (1/23). Analysis of the dendrogram showed that multidrug resistance and CTX-M ESBL groups were distributed among all strains, independent of clonality and phylogroup. Sequence types (STs) associated with pandemic resistance clones, such as B2-ST131 and D-ST648, were observed among the isolates. In conclusion, the results showed worrisome evidence of the potential for antibiotic multiresistant dissemination among community-acquired urinary tract infection caused by UPEC.

Gonçalves LF ，de Oliveira Martins-Júnior P ，de Melo ABF ，da Silva RCRM ，de Paulo Martins V ，Pitondo-Silva A ，de Campos TA ... -  《-》

Dissemination of ST131 and ST393 community-onset, ciprofloxacin-resistant Escherichia coli clones causing urinary tract infections in Korea.

Ciprofloxacin-resistant Escherichia coli is growing concern in clinical settings. In this study, we investigated the distribution of virulence determinants and phylogenetic groups among community-onset, ciprofloxacin-resistant E. coli isolates causing urinary tract infections (UTIs) in Korea. In addition, the evidence of clonal spread in the community was also examined. From November 2006 to August 2007, 543 community-onset E. coli isolates causing UTIs were collected as part of a multicenter surveillance study. In vitro susceptibility testing was performed using broth microdilution method. Distribution of virulence determinants and phylogenetic groupings were examined. In addition, multilocus sequence typing (MLST) analysis was performed. In vitro antimicrobial susceptibility testing revealed that 154 isolates (28.4%) were ciprofloxacin-resistant. Of these, 129 ciprofloxacin-resistant E. coli isolates were further characterized. As a result of phylogenetic subgrouping, we found that phylogenetic subgroup D was the most predominant (46 isolates, 35.7%), followed by B2 (44 isolates, 34.1%), A (21 isolates, 16.3%), and B1 (18 isolates, 14.0%). MLST analysis showed 48 sequence types (STs). The most prevalent ST was ST131 (32 isolates, 24.8%), followed by ST393 (23 isolates, 17.8%). While all ST131 isolates belonged to phylogenetic subgroup B2, which is known to be a highly virulent, all ST393 isolates belonged to subgroup D. ST131 and ST393 showed different profiles of virulence factors; papA, papG allele III, and traT genes were significantly more prevalent in ST131 than in ST393 (p values, <0.001). Based on genotyping, it is suggested that epidemic and virulent ciprofloxacin-resistant E. coli clones such as ST131 and ST393 have disseminated in Korea. However, the diversity of CTX-M genes in ST131 isolates may indicate that ESBL genes have been acquired independently or several ESBL-producing, ciprofloxacin-resistant E. coli clones may have disseminated in the Korean community.

Lee MY ，Choi HJ ，Choi JY ，Song M ，Song Y ，Kim SW ，Chang HH ，Jung SI ，Kim YS ，Ki HK ，Son JS ，Kwon KT ，Heo ST ，Yeom JS ，Shin SY ，Chung DR ，Peck KR ，Song JH ，Ko KS ... -  《-》

Prevalence of fluoroquinolone-resistant and broad-spectrum cephalosporin-resistant community-acquired urinary tract infections in Rio de Janeiro: Impact of Escherichia coli genotypes ST69 and ST131.

Uropathogenic Escherichia coli (UPEC) is the leading cause of community-acquired urinary tract infection (CA-UTI). The increasing prevalence of CA-UTI caused by UPEC strains resistant to broad-spectrum drugs complicates clinical management of these infections. Here we assessed the prevalence of antimicrobial drug resistance, genotypes and beta-lactamase genes among UPEC isolated from cases of CA-UTI in Rio de Janeiro, Brazil during November 2015 to determine if the prevalence of drug-resistant CA-UTI is determined by multiple genotypes of resistant UPEC or dissemination of key lineages of UPEC. Among 499 UPEC isolates, 98 (20%) were ciprofloxacin (CIP) resistant and 41 (8%) produced extended-spectrum beta-lactamase (ESBL). Sequence types (ST) 69 and 131 were the most common genotypes, representing 77 (15%) and 42 (8%) of all UPEC isolates, respectively. Of fluoroquinolone-resistant isolates, ST69 and ST131 together accounted for 57%, while of ESBL-producers, ST131 represented 21%. Only 5 (2%) of 255 susceptible isolates belonged to these STs (p < .001). blaCTX-M-15 was detected in 17 (42%) of the 41 ESBL-producing isolates. Comparison with a collection of UPEC isolates obtained a decade earlier from the same community showed that a large proportion (60% and 25%, respectively) of the increase in CA-UTI caused by fluoroquinolone-resistant and ESBL-producing UPEC appears to be due to just two pandemic lineages ST131 and ST69. These findings indicate that much of the prevalence of broad-spectrum drug-resistant CA-UTI in Rio de Janeiro is due to a limited set of pandemic lineages of UPEC circulating in the community instead of multiple genotypes selected by antimicrobial agents.

de Souza da-Silva AP ，de Sousa VS ，de Araújo Longo LG ，Caldera S ，Baltazar ICL ，Bonelli RR ，Santoro-Lopes G ，Riley LW ，Moreira BM ... -  《-》

Lower prevalence of hlyD, papC and cnf-1 genes in ciprofloxacin-resistant uropathogenic Escherichia coli than their susceptible counterparts isolated from southern India.

The study was conducted to determine the association of the hlyD, papC and cnf-1 virulence genes with drug resistance in uropathogenic Escherichia coli (UPEC) isolated from cases of urinary tract infection (UTI). A total of 193 E. coli strains isolated from symptomatic cases of UTI in a tertiary care teaching hospital in Raichur, Northern Karnataka, India were included in the study. The antibiotic susceptibility pattern was determined by Kirby-Bauer's Disk Diffusion method, and the strains resistant to any of the third generation cephalosporins tested were further confirmed for extended-spectrum beta-lactamase (ESBL)-production by an E-strip test. Genotypic virulence markers, namely, hlyD, papC and cnf-1, were detected by the uniplex PCR method and the phylogenetic characterization was performed by a multiplex PCR assay. The majority of the E. coli isolates belonged to the B2 phylogenetic group were significantly associated with ciprofloxacin-sensitivity and non-ESBL production (p<0.05). An increased prevalence of ciprofloxacin-sensitive strains over ciprofloxacin-resistant strains were observed among the UPEC isolates harboring the papC (72.9% vs. 40.2%; p<0.001), hlyD (43.7% vs. 21.6%; p<0.001) and cnf-1 (30.2% vs. 12.3%; p<0.05) genes. The presence of a multivirulent gene in the non-ESBL E. coli strains (44.5%) was significantly higher (p<0.05) than in the ESBL-producing strains (21%). Among the UPEC isolates, the predominant B2 phylogenetic group was significantly associated with the ciprofloxacin-sensitive strains, as well as with the non-ESBL E. coli strains. The genotypic virulence markers of UPEC were associated with ciprofloxacin-sensitivity, and a significant number of the non-ESBL strains harbored multivirulent genes. The relationship between the presence of the virulence genes and ESBL production was complex and warrants further intensive studies.

Harwalkar A ，Gupta S ，Rao A ，Srinivasa H ... -  《-》