Prevalence of Pathogenicity Islands and Fim H Virulence Genes in Escherichia coli Strains Isolated from Urinary Tract Infection in 
Rasht City, Iran

To clarify whether prevalence or special pathogenicity is more important in determining urinary tract infection (UTI) causation, we compared the biotype, phylogenetic group, and virulence genes of Escherichia coli urine strains from 11 women with acute lower UTI with those of the host's dominant intestinal E. coli strain(s). Twenty-one unique E. coli clones were identified. For three women, the single faecal clone identified was also the host's urine clone, whereas for eight women faecal samples yielded 1 or 2 distinct non-urine clones (total, n=10), either with (n=3) or without (n=5) the concurrent urine clone. The eight urine clones from the latter eight women exhibited significantly greater inferred virulence, according to virulence gene content and phylogenetic background, than did the hosts' 10 corresponding ‘faecal only’ clones. In contrast, the three urine clones that were detected as the host's sole faecal clone exhibited significantly lower inferred virulence than the other eight urine clones, and were statistically indistinguishable from the 10 ‘faecal only’ clones. In conclusion, special pathogenicity is an important determinant of UTI pathogenesis in women, although prevalence may occasionally allow less virulent strains to cause UTI.

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Virulence genes and phylogenetic groups of uropathogenic Escherichia coli isolates from patients with urinary tract infection and uninfected control subjects: a case-control study

BMC Infectious Diseases ◽

10.1186/s12879-021-06036-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Seyedeh Elham Rezatofighi ◽

Mahsa Mirzarazi ◽

Mansour Salehi

Keyword(s):

Escherichia Coli ◽

Urinary Tract Infection ◽

Urinary Tract ◽

Tract Infection ◽

Virulence Factors ◽

Virulence Genes ◽

Strong Association ◽

Phylogenetic Groups ◽

E Coli ◽

Healthy Humans

Abstract Background Urinary Tract Infection (UTI) is one of the most common bacterial infectious diseases which causes considerable morbidity and costly health problems. Uropathogenic Escherichia coli (UPEC), the most common pathogen causing UTI, is a highly heterogeneous group of extraintestinal pathogenic E. coli (ExPEC) which may carry a variety of virulence factors and belonging to different phylogenetic backgrounds. The current study aimed to investigate the frequency and association between various virulence factors (VFs) and phylogenetic groups of UPEC and commensal isolates. Methods UPEC and commensal E. coli strains isolated from UTI and feces of healthy humans were compared for the presence of VFs and phylogenetic groups. Association between virulence genes was investigated and cluster analysis was employed. Results According to the results, among a 30 virulence markers tested, the pathogenicity-associated island (PAI), papAH, papEF, fimH, fyuA, and traT genes prevalence were statistically significant in UPEC isolates. A strong association was found between the B2 and D phylogenetic groups and clinical isolates of UPEC; while, commensal isolates were mostly associated with phylogenetic group A. The aggregated VFs scores were more than twice higher in the UPEC isolates in comparison with the commensal isolates. Interestingly, the B2 group in both UPEC and commensal isolates had the highest VF scores. A strong positive association was found between several virulence genes. The clustering results demonstrated that UPEC or commensal E. coli isolates were highly heterogeneous due to different composition of their virulence gene pool and pathogenicity islands. Conclusion Genetic structure and VFs of UPEC strains vary from region to region; therefore, to control the UTI, the epidemiological aspects and characterization of the UPEC isolates need to be investigated in different regions. Since UPEC isolates are generally originate from the commensal strains, it may be feasible to reduce the UTI burden by interfering the intestinal colonization, particularly in the highly pathogenic clonal lineages such as B2.

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Distribution of Uropathogenic Virulence Genes in Escherichia coli Isolated from Children with Urinary Tract Infection in Sanandaj, Iran

Archives of Pediatric Infectious Diseases ◽

10.5812/pedinfect.41995 ◽

2017 ◽

Vol In press (In press) ◽

Cited By ~ 2

Author(s):

Maryam Pourzare ◽

Safoura Derakhshan ◽

Daem Roshani

Keyword(s):

Escherichia Coli ◽

Urinary Tract Infection ◽

Urinary Tract ◽

Tract Infection ◽

Virulence Genes

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Enteroaggregative Escherichia coli is associated with antibiotic resistance and urinary tract infection symptomatology

PeerJ ◽

10.7717/peerj.11726 ◽

2021 ◽

Vol 9 ◽

pp. e11726

Author(s):

Verónica I. Martínez-Santos ◽

María Ruíz-Rosas ◽

Arturo Ramirez- Peralta ◽

Oscar Zaragoza García ◽

Luis Armando Resendiz-Reyes ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract Infection ◽

Antibiotic Resistance ◽

Urinary Tract ◽

Tract Infection ◽

Virulence Genes ◽

Clinical Isolates ◽

E Coli ◽

Ambulatory Patients ◽

Tract Infections

Background Uropathogenic Escherichia coli (UPEC) is the causative agent of uncomplicated urinary tract infections (UTIs) in ambulatory patients. However, enteroaggregative E. coli (EAEC), an emergent bacterial pathogen that causes persistent diarrhoea, has recently been associated with UTIs. The aim of this study was to determine the frequency of EAEC virulence genes, antibiotic resistance, as well as biofilm production of UPEC isolates obtained from ambulatory patients with non-complicated UTIs that attended to the ISSSTE clinic in Chilpancingo, Guerrero, Mexico, and correlate these with the patients’ urinary tract infection symptomatology. Methods One hundred clinical isolates were obtained. The identification of clinical isolates, antimicrobial susceptibility testing, and extended spectrum beta-lactamases (ESBLs) production were performed using the Vitek automated system. Assignment of E. coli phylogenetic groups was performed using the quadruplex phylo-group assignment PCR assay. UPEC virulence genes (hlyA, fimH, papC, iutA, and cnf1) and EAEC virulence genes (aap, aggR, and aatA) were detected by multiple PCR. Results We found that 22% of the isolates carried the aggR gene and were classified as UPEC/EAEC. The main phylogenetic group was B2 (44.1% were UPEC and 77.27% UPEC/EAEC isolates, respectively). Over half of the UPEC/EAEC isolates (63.64%) were obtained from symptomatic patients, however the aatA gene was the only one found to be associated with the risk of developing pyelonephritis (OR = 5.15, p = 0.038). A total of 77.71% of the UPEC/EAEC isolates were ESBL producers and 90.91% multidrug-resistant (MDR). In conclusion, UPEC/EAEC isolates are more frequent in symptomatic patients and the aatA gene was associated with a higher risk of developing pyelonephritis, along with UPEC genes hlyA and cfn1. UPEC/EAEC isolates obtained from UTI showed ESBL production and MDR.

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