Escherichia coli Bloodstream Infections in Patients at a University Hospital: Virulence Factors and Clinical Characteristics

Abstract

Extraintestinal pathogenic Escherichia coli (ExPEC) isolates are responsible for many bloodstream infections. The aim of this study was to characterize E. coli isolated from the bloodstreams of patients ( n = 48) at the University Hospital in Brazil. Epidemiological data were obtained through the analysis of medical records and laboratory tests. By PCR analysis, we investigated the presence of virulence factors (VFs), pathogenicity islands (PAIs), extended-spectrum β-lactamase (ESBL), phylogenetic classifications (A, B1, B2, C, D, E, and F) and molecular genotype by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The mortality analysis showed that 33.3% of the deaths were associated with bacteraemia due to E. coli infections; in addition, an age between 60 and 75 years ( p < 0.001; OR = 6.3[2.1–18.9]) and bacteraemia with an abdominal origin ( p = 0.02; OR = 5[1.2–20.5]) were risk factors for the severity of the infection. Additionally, the presence of the afa gene was associated with mortality due to E. coli bacteraemia ( p = 0.027; OR = 11.4[1.5–85.7]). Immunosuppression (27.1%), intestinal diseases (25.0%) and diabetes (18.8%), were prevalent among patients, and most of the bacteraemia cases were secondary to urinary tract infections (50.0%). The serum resistance gene tra T was present in 77.1% of isolates, group capsular 2 ( kpsMT II) was present in 45.8% and the K5 capsule was present in 20.8% of isolates. The isolates also showed a high prevalence for the siderophore yersiniabactina ( fyu A) (70.8%) and PAI IV 536 (77.1%). Phylogenetic analysis showed that group B2 (45.8%) was the most prevalent, and was the phylogroup that had a higher prevalence of VFs and PAIs. However, in this study, a considerable number of isolated bacteria were classified as group B1 (18.8%) and as group E (14.6%). Eight (16.7%) isolates were resistant to third and fourth generation cephalosporin and group CTX-M-1 (CTX-M-15) was the most prevalent ESBL type. The molecular genotyping showed two clonal lineages and several isolates that were not related to each other. This study provides additional information on the epidemiological and molecular characteristics of E. coli bloodstream infections in Brazil.

<p>Prevalence of Virulence Genes and Their Association with Antimicrobial Resistance Among Pathogenic <em>E. coli</em> Isolated from Egyptian Patients with Different Clinical Infections</p>

“…Also, it was found associated with isolates of urinary tract infections that may give rise to bacteremia. 65,66 This study showed that traT was more common among E. coli isolated from urine and blood samples (59.1% and 55.5%, respectively). E. coli with serum resistance were highly virulent, as they can escape the complement system and promote serum survival and increase the risk of developing septic shock and the increase in mortality.…”

Pathogenicity Factors of Genomic Islands in Intestinal and Extraintestinal Escherichia coli

“…Their adhesin FimH binds to glycosylated uroplakin and α1β3 (Korhonen et al, 1985;Guyer et al, 2000,? ;Russo et al, 2001;Bingen-Bidois et al, 2002;Johnson et al, 2002Johnson et al, , 2004Johnson et al, , 2008Marrs et al, 2002;Bonacorsi et al, 2003;Russo, 2003;Srinivasan et al, 2003;Buckles et al, 2004;Bonacorsi and Bingen, 2005;Parham et al, 2005a;Rendón et al, 2007;Restieri et al, 2007;Ananias and Yano, 2008;Henderson et al, 2009;Schubert et al, 2010;Ejrnaes et al, 2011;Mahjoub-Messai et al, 2011;Vejborg et al, 2011;Lehti et al, 2012;Qin et al, 2013;Tarchouna et al, 2013;Firoozeh et al, 2014;Basmaci et al, 2015;Nagarjuna et al, 2015;Wijetunge et al, 2015;Beck et al, 2016;Cordeiro et al, 2016;Lee and Lee, 2018;Daga et al, 2019;Nojoomi and Ghasemian, 2019;Raimondi et al, 2019;Sarowska et al, 2019 integrins covering the apical surface of uroepithelium cells, thereby promoting the invasion of host cells and the development of IBCs (Connell et al, 1996;Martinez et al, 2000;Gunther et al, 2002;Mysorekar and Hultgren, 2006;…”

Genetic Determinants of Resistance to Extended-Spectrum Cephalosporin and Fluoroquinolone in Escherichia coli Isolated from Diseased Pigs in the United States

“…In addition to the above-mentioned properties, IncF plasmids also possessed virulence genes which can contribute to the fitness of bacterial clones inside mammalian hosts. For example, the traT gene related to serum resistance was found on every bla CTX-M -harboring IncF plasmid, except for IncF (F24:A-:B1), and this gene has been consistently associated with urinary tract infections and sepsis in humans (71)(72)(73)(74). Similarly, hlyF (hemolysin), iutA (iron uptake), and ompT (outer membrane protease) genes present on some of the bla CTX-M -IncF plasmids are very commonly found in avian pathogenic E. coli (75).…”