Escherichia coli clonal group A causing bacteraemia of urinary tract origin

Abstract

Escherichia coli clonal group A (CgA) causes disease in humans. This is the first study investigating the prevalence of CgA among E. coli from non-urine, extraintestinal infections in a northern European country. E. coli blood (n = 196) and paired urine (n = 195) isolates from the same patients with bacteraemia of urinary tract origin were analysed. The isolates were collected from January 2003 through May 2005 at four hospitals in Copenhagen, Denmark. Pulsed-field gel electrophoresis (PFGE) patterns, antimicrobial resistance and patient characteristics were determined for all CgA isolates; presence of virulence-associated genes (VAGs) and serotypes were determined for the blood CgA isolates. Thirty blood isolates (15%) belonged to CgA. CgA blood isolates were associated with female patients and sulfamethoxazole-trimethoprim resistance and they harboured a distinctive VAG profile. The blood and urine isolates from each pair were found to be related in 26 of 27 CgA blood/urine pairs, confirming a urinary tract origin of infection. Furthermore, a relationship between the PFGE patterns of CgA blood/urine isolates and CgA isolates from UTI patients in general practice and a CgA isolate from a community-dwelling human reported previously, was found, suggesting a community origin of CgA. The finding of CgA strains in 15% of the E. coli bloodstream infections with a urinary tract origin in Denmark suggests that CgA constitutes an important clonal lineage among extraintestinal pathogenic E. coli. A reservoir of this pathogenic E. coli group in the community causing not only UTI but also more severe infections such as bacteraemia has implications for public health.

E. coli Bacteremia Strains - High diversity and Associations with Agerelated Clinical Phenomena

“…The statistical power in this evaluation was low, and may not be comparable to a level of 15% of isolates found in a study of E. coli bacteremia of urinary tract origin [35]. Our findings support the insight that also phylogroup A E. coli can cause severe infection from a variety of sources, including urinary tract origin.…”

Pandemic lineages of extraintestinal pathogenic Escherichia coli

“…By MLST, CgA strains were subsequently found to belong to the ST69 complex [56]. ST69 strains belong to ECOR phylogenetic group D and serogroups that include O11, O15, O17, O44, O73, O77, O86, O125ab, and O25b [11,14,[56][57][58]. The prototype ST69 strain (O11; ATCC BAA-457) has the VF profile shown in Table 2 [59,60].…”

“…Since the first recognition in 1999, CgA and ST69 strains have been reported from many other regions of the world from both community-acquired and healthcare-associated UTIs and BSIs [8,57,[61][62][63][64][65]. Most strains are multidrug-resistant, and typically harbour a single arrangement of a gene cassette (dfrA17-aadA5) encoding dihydrofolate reductase and aminoglycoside adenyltransferase, respectively, on a class I integron [66,67].…”

Unusual pathogenic B1 genotype (yjaA/TspE4.C2) detected among Escherichia coli from pig, chicken broiler meat and human extraintestinal infection

“…The authors suggested this specific genotype to be uncommon and proposed assignment to the phylogenetic group B2 because of the multi-locus sequence type (MLST), pathogenicity-associated islands and quinolone susceptibility (Mendonça et al, 2011). The aim of our study was to investigate the occurrence of the yjaA/ Clermont et al (2000) (Jakobsen et al, 2010b;Skjøt-Rasmussen et al, 2012). Of the 1355 isolates, 205 belonged to phylogroup B1, of which four presented the yjaA/TspE4.C2 profile.…”

“…To understand their virulence potential, the four isolates were screened for the presence of 23 virulence-associated genes (VAGs) with known or suspected relevance to the pathogenesis of ExPEC (Table 1) (Ejrnaes et al, 2011;Skjøt-Rasmussen et al, 2012). The pig isolate harboured two VAGs, whereas the meat isolate harboured five VAGs and the human isolates harboured the same 12 VAGs (Table 1).…”