Carbapenem Resistance Profiles of Pathogenic Escherichia coli in Uganda

Escherichia coli has been implicated as one of the main etiological agents of diarrhea, urinary tract infections, meningitis and septicemia worldwide. The ability to cause diseases is potentiated by presence of virulence factors. The virulence factors influence the capacity of E. coli to infect and colonize different body systems. Thus, pathogenic E. coli are grouped into DEC strains that are mainly clustered in phylogenetic group B1 and A; ExPEC belonging to A, B2 and D. Coexistence of virulence and beta-lactamase encoding genes complicates treatment outcomes. Therefore, this study aimed at presenting the carbapenem resistance (CR) profiles among pathogenic E. coli. This was a retrospective cross-sectional study involving use of 421 archived E. coli clinical isolates collected in 2019 from four Uganda tertiary hospitals. The isolates were subjected to antibiotics sensitivity assays to determine phenotypic resistance. Four sets of multiplex PCR were performed to detect CR genes, DEC pathotypes virulence genes, ExPEC PAI and the E. coli phylogenetic groups. Antibiotic susceptibility revealed that all the 421 E. coli isolates used were MDR as they exhibited 100% resistance to more than one of the first-line antibiotics. The study registered phenotypic and genotypic CR prevalence of 22.8% and 33.0% respectively. The most predominant gene was blaOXA-48 with genotypic frequency of 33.0%, then blaVIM (21.0%), blaIMP (16.5%), blaKPC (14.8%) and blaNDM (14.8%). Spearman’s correlation revealed that presence of CR genes was highly associated with phenotypic resistance. Furthermore, of 421 MDR E. coli isolates, 19.7% harboured DEC virulence genes, where EPEC recorded significantly higher prevalence (10.8%) followed by S-ETEC (3.1%), STEC (2.9%), EIEC (2.0%) and L-ETEC (2.0%). Genetic analysis characterized 46.1% of the isolates as ExPEC and only PAI IV536 (33.0%) and PAI IICFT073 (13.1%) were detected. Phylogenetic group B2 was predominantly detected (41.1%), followed by A (30.2%), B1(21.6%), and D (7.1%). Furthermore, 38.6% and 23.1% of the DEC and ExPEC respectively expressed phenotypic resistance. Our results exhibited significant level of CR carriage among the MDR DEC and ExPEC clinical isolates belonging to phylogenetic groups B1 and B2 respectively. Virulence and CR genetic factors are mainly located on mobile elements. Thus, constitutes a great threat to the healthcare system as this promotes horizontal gene transfer.

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Carbapenem Resistance Profiles of Pathogenic Escherichia coli in Uganda

10.21203/rs.3.rs-125368/v1 ◽

2020 ◽

Author(s):

Kenneth Ssekatawa ◽

Denis K Byarugaba ◽

Jesca L. Nakavuma ◽

Charles Drago Kato ◽

Francis Ejobi ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Factors ◽

Phylogenetic Group ◽

Clinical Isolates ◽

Genotypic Frequency ◽

Phylogenetic Groups ◽

Cross Sectional ◽

Phenotypic Resistance ◽

E Coli ◽

Tract Infections

Abstract Background: Escherichia coli has been implicated as one of the main etiological agents of diarrhea, urinary tract infections, meningitis and septicemia worldwide. The ability to cause diseases is potentiated by presence of virulence factors. The virulence factors influence the capacity of E. coli to infect and colonize different body systems. Thus, pathogenic E. coli are grouped into DEC strains that are mainly clustered in phylogenetic group B1 and A; ExPEC belonging to A, B2 and D. Coexistence of virulence and beta-lactamase encoding genes complicates treatment outcomes. Therefore, this study aimed at presenting the CR profiles among pathogenic E. coli. Methods: This was a retrospective cross-sectional study involving use of archived E. coli clinical isolates collected in 2019 from four Ugandan tertiary hospitals. The isolates were subjected to antibiotics sensitivity assays to determine phenotypic resistance. Four sets of multiplex PCR were performed to detect CR genes, DEC pathotypes virulent genes, ExPEC PAI and the E. coli phylogenetic groups. Results: Antibiotic susceptibility revealed that all the 421 E. coli isolates used were MDR as they exhibited 100% resistance to more than one of the first-line antibiotics. The study registered phenotypic and genotypic CR prevalence of 22.8% and 33.0% respectively. The most predominant gene was blaOXA-48 with genotypic frequency of 33.0%, then blaVIM(21.0%), blaIMP(16.5%), blaKPC(14.8%) and blaNDM(14.8%). Spearman’s correlation revealed that presence of CR genes was highly associated with phenotypic resistance. Furthermore, of 421 MDR E. coli isolates, 19.7% harboured DEC virulent genes, where EPEC recorded significantly higher prevalence (10.8%) followed by S-ETEC(3.1%), STEC(2.9%), EIEC (2.0%) and L-ETEC(2.0%). Genetic analysis characterized 46.1% of the isolates as ExPEC and only PAI IV536(33.0%) and PAI IICFT073(13.1%) were detected. Phylogenetic group B2 was predominantly detected (41.1%), followed by A(30.2%), B1(21.6%), and D(7.1%). Furthermore, 38.6% and 23.1% of the DEC and ExPEC respectively expressed phenotypic resistance.Conclusion: Our results exhibited significant level of CR carriage among the MDR DEC and ExPEC clinical isolates belonging to phylogenetic groups B1 and B2 respectively. Virulence and CR genetic factors are mainly located on mobile elements. Thus, constitutes a great threat to the healthcare system as it promotes horizontal gene transfer.

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Carbapenem resistance profiles of Pathogenic Escherichia coli in Uganda

10.21203/rs.3.rs-103468/v1 ◽

2020 ◽

Author(s):

Kenneth Ssekatawa ◽

Denis K Byarugaba ◽

Jesca L. Nakavuma ◽

Charles Drago Kato ◽

Francis Ejobi ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Factors ◽

Phylogenetic Group ◽

Clinical Isolates ◽

Genotypic Frequency ◽

Phylogenetic Groups ◽

Cross Sectional ◽

Phenotypic Resistance ◽

E Coli ◽

Tract Infections

Abstract Background: Escherichia coli has been implicated as one of the main etiological agents of diarrhea, urinary tract infections, meningitis and septicemia worldwide. The ability to cause diseases is potentiated by presence of virulence factors. The virulence factors influence the capacity of E. coli to infect and colonize different body systems. Thus, pathogenic E. coli are grouped into DEC strains that are mainly clustered in phylogenetic group B1 and A; ExPEC belonging to A, B2 and D. Coexistence of virulence and beta-lactamase encoding genes complicates treatment outcomes. Therefore, this study aimed at presenting the CR profiles among pathogenic E. coli. Methods: This was a retrospective cross-sectional study involving use of archived E. coli clinical isolates collected in 2019 from four Ugandan tertiary hospitals. The isolates were subjected to antibiotics sensitivity assays to determine phenotypic resistance. Four sets of multiplex PCR were performed to detect CR genes, DEC pathotypes virulent genes, ExPEC PAI and the E. coli phylogenetic groups. Results:Antibiotic susceptibility revealed that all the 421 E. coli isolates used were MDR as they exhibited 100% resistance to more than one of the first-line antibiotics. The study registered phenotypic and genotypic CR prevalence of 22.8% and 33.0% respectively. The most predominant gene was blaOXA-48 with genotypic frequency of 33.0%, then blaVIM(21.0%), blaIMP(16.5%), blaKPC(14.8%) and blaNDM(14.8%). Spearman’s correlation revealed that presence of CR genes was highly associated with phenotypic resistance. Furthermore, of 421 MDR E. coli isolates, 19.7% harboured DEC virulent genes, where EPEC recorded significantly higher prevalence (10.8%) followed by S-ETEC(3.1%), STEC(2.9%), EIEC (2.0%) and L-ETEC(2.0%). Genetic analysis characterized 46.1% of the isolates as ExPEC and only PAI IV536(33.0%) and PAI IICFT073(13.1%) were detected. Phylogenetic group B2 was predominantly detected (41.1%), followed by A(30.2%), B1(21.6%), and D(7.1%). Furthermore, 38.6% and 23.1% of the DEC and ExPEC respectively expressed phenotypic resistance.Conclusion: Our results exhibited significant level of CR carriage among the MDR DEC and ExPEC clinical isolates belonging to phylogenetic groups B1 and B2 respectively. Virulence and CR genetic factors are mainly located on mobile elements. Thus, constitutes a great threat to the healthcare system as it promotes horizontal gene transfer.

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Comparison of Escherichia coli isolates implicated in human urinary tract infection and avian colibacillosis

Microbiology ◽

10.1099/mic.0.27499-0 ◽

2005 ◽

Vol 151 (6) ◽

pp. 2097-2110 ◽

Cited By ~ 227

Author(s):

Kylie E. Rodriguez-Siek ◽

Catherine W. Giddings ◽

Curt Doetkott ◽

Timothy J. Johnson ◽

Mohamed K. Fakhr ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract Infection ◽

Urinary Tract ◽

Virulence Genes ◽

Phylogenetic Group ◽

Human Beings ◽

Phylogenetic Groups ◽

E Coli ◽

Phylogenetic groups and antimicrobial susceptibility patterns of uropathogenic Escherichia coli clinical isolates from patients at Mulago National Referral Hospital, Kampala, Uganda

F1000Research ◽

10.12688/f1000research.20930.1 ◽

2019 ◽

Vol 8 ◽

pp. 1828 ◽

Cited By ~ 1

Author(s):

Paul Katongole ◽

Daniel Bulwadda Kisawuzi ◽

Henry Kyobe Bbosa ◽

David Patrick Kateete ◽

Christine Florence Najjuka

Keyword(s):

Escherichia Coli ◽

Antimicrobial Susceptibility ◽

Phylogenetic Group ◽

Diffusion Method ◽

Clinical Microbiology Laboratory ◽

Phylogenetic Groups ◽

E Coli ◽

Pcr Method ◽

Tract Infections ◽

Susceptibility Patterns

Introduction: Uropathogenic Escherichia coli (UPEC) remains the most common cause of urinary tract infections (UTIs). They account for over 80-90% of all community-acquired and 30-50% of all hospital-acquired UTIs. E. coli strains have been found to belong to evolutionary origins known as phylogenetic groups. In 2013, Clermont classified E. coli strains into eight phylogenetic groups using the quadruplex PCR method. The aim of this study was to identify the phylogenetic groups of UPEC strains in Uganda using Clermont’s quadruplex PCR method and to assess their antibiotic susceptibility patterns in Uganda. Methods: In this cross-sectional study, 140 stored uropathogenic E. coli isolates from the Clinical Microbiology Laboratory, Department of Medical Microbiology, College of Health Sciences Makerere University were subjected to phylogenetic typing by a quadruplex PCR method. Antimicrobial susceptibility testing was performed by disk diffusion method according to Clinical & Laboratory Standards Institute (CLSI) guidelines. Phenotypic detection of extended-spectrum beta-lactamase, AmpC and carbapenemases was done according to CLSI guidelines and Laboratory SOPs. Results: Phylogenetic group B2 (40%) was the most predominant, followed by A (6.23%), clade I and II (5%), D and E (each 2.14%), B1 (1.43%) and F and C (each 0.71%). The most common resistant antibiotic was trimethoprim-sulphamethoxazole (90.71%) and the least was imipenem (1.43%). In total, 73.57% of isolates were multi-drug resistant (MDR). Antibiotic resistance was mainly detected in phylogenetic group B2 (54%). Conclusions: Our findings showed the high prevalence of MDR E. coli isolates, with the dominance of phylogenetic group B2. About 9% of E. coli isolates belonged to the newly described phylogroups C, E, F, and clade I and II.

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Detection of virulence genes, phylogenetic group and antibiotic resistance of uropathogenic Escherichia coli in Mongolia

The Journal of Infection in Developing Countries ◽

10.3855/jidc.7903 ◽

2017 ◽

Vol 11 (01) ◽

pp. 51-57 ◽

Cited By ~ 17

Author(s):

Yandag Munkhdelger ◽

Nyamaa Gunregjav ◽

Altantsetseg Dorjpurev ◽

Nishi Juniichiro ◽

Jav Sarantuya

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Virulence Genes ◽

Wide Spectrum ◽

Iron Acquisition ◽

Uropathogenic Escherichia Coli ◽

Phylogenetic Group ◽

Diffusion Method ◽

Phylogenetic Groups ◽

E Coli

Introduction: The severity of urinary tract infection (UTI) produced by uropathogenic Escherichia coli (UPEC) is due to the expression of a wide spectrum of virulence genes. E. coli strains were divided into four phylogenetic groups (A, B1, B2 and D) based on their virulence genes. The present study aimed to assess the relationship between virulence genes, phylogenetic groups, and antibiotic resistance of UPEC. Methodology: A total of 148 E. coli were tested for antimicrobial resistance against 10 drugs using the disk diffusion method. The isolates were screened by polymerase chain reaction (PCR) for detection of virulence genes and categorized into the four major phylogenetic groups. Results: Phylogenetic group B2 was predominant (33.8%), followed by D (28.4%), A (19.6), and B1 (18.2%). A higher prevalence of fimH (89.9%), fyuA (70.3%), traT (66.2%), iutA (62.2%), kpsMTII (58.8%), and aer (56.1%) genes were found in UPEC, indicating a putative role of adhesins, iron acquisition systems, and protectins that are main cause of UTIs. The most common antibiotic resistance was to cephalotin (85.1%), ampicillin (78.4%) and the least to nitrofurantoin (5.4%) and imipenem (2%). In total, 93.9% of isolates were multidrug resistant (MDR). Conclusions: This study showed that group B2 and D were the predominant phylogenetic groups and virulence-associated genes were mostly distributed in these groups. The virulence genes encoding components of adhesins, iron acquisition systems, and protectins were highly prevalent among antibiotic-resistant UPEC. Although the majority of strains are MDR, nitrofurantoin is the drug of choice for treatment of UTI patients in Ulaanbaatar.

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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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Bacterial Morphotypes as Important Trait for Uropathogenic E. coli Diagnostic; a Virulence-Phenotype-Phylogeny Study

Microorganisms ◽

10.3390/microorganisms9112381 ◽

2021 ◽

Vol 9 (11) ◽

pp. 2381

Author(s):

Manuel G. Ballesteros-Monrreal ◽

Margarita M. P. Arenas-Hernández ◽

Edwin Barrios-Villa ◽

Josue Juarez ◽

Maritza Lizeth Álvarez-Ainza ◽

...

Keyword(s):

Urinary Tract ◽

Virulence Genes ◽

Clinical Isolates ◽

Phylogenetic Groups ◽

Urine Sediment ◽

Antibiotic Resistant ◽

E Coli ◽

Important Trait ◽

Tract Infections ◽

Bacterial Morphotypes

Urinary tract infections (UTIs) belong to the most common pathologies in Mexico and are mainly caused by Uropathogenic Escherichia coli (UPEC). UPEC possesses a wide diversity of virulence factors that allow it to carry out its pathogenesis mechanism in the urinary tract (UT). The development of morphotypes in UT represents an important feature of UPEC because it is associated with complications in diagnosis of UTI. The aim of this study was to determine the presence of bacterial morphotypes, virulence genes, virulence phenotypes, antibiotic resistant, and phylogenetic groups in clinical isolates of UPEC obtained from women in Sonora, Mexico. Forty UPEC isolates were obtained, and urine morphotypes were observed in 65% of the urine samples from where E. coli was isolated. Phylogenetic group B2 was the most prevalent. The most frequent virulence genes were fimH (100%), fliCD (90%), and sfaD/focC (72%). Biofilm formation (100%) and motility (98%) were the most prevalent phenotypes. Clinical isolates showed high resistance to aminoglycosides and β-lactams antibiotics. These data suggest that the search for morphotypes in urine sediment must be incorporated in the urinalysis procedure and also that clinical isolates of UPEC in this study can cause upper, lower, and recurrent UTI.

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Detection of Phylogenetic Groups and Drug Resistance Genes of Escherichia coli Causing Urinary Tract Infection in Southwest Iran

Jundishapur Journal of Microbiology ◽

10.5812/jjm.112547 ◽

2021 ◽

Vol 14 (2) ◽

Author(s):

Mostafa Boroumand Boroumand ◽

Mohsen Naghmachi ◽

Mohammad Amin Ghatee

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Urinary Tract ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Phylogenetic Group ◽

Phylogenetic Groups ◽

E Coli ◽

Pcr Method ◽

Tract Infections

Background: Many bacteria can cause urinary tract infections (UTIs), among which Escherichia coli is the most common causative agent. E. coli strains are divided into eight phylogenetic groups based on the new Quadroplex-PCR method, which are different in terms of patterns of resistance to antibiotics, virulence, and environmental characteristics. Objectives: This study aimed to determine the phylogenetic groups and the prevalence of drug resistance genes in E. coli strains causing UTIs. Methods: In this descriptive cross-sectional study, 129 E. coli isolates obtained from the culture of patients with UTIs were evaluated for phylogenetic groups using the new method of Clermont et al. The identification of phylogenetic groups and antibiotic resistance genes was performed using the multiplex polymerase chain reaction (PCR) method. Results: In this study, concerning the distribution of phylogenetic groups among E. coli isolates, the phylogenetic group B2 (36.4%) was the most common phylogenetic group, followed by phylogroups C (13.2%), clade I (10.1%), D (9.3%), and A (3.1%) while groups B1 and F were not observed in any of the isolates, and 20.2% had an unknown state. Also, out of 129 E. coli isolates, the total frequency of tetA, tetB, sul1, sul2, CITM, DfrA, and qnr resistance genes was 59.7%, 66.7, 69, 62, 30.2, 23.3, and 20.2%, respectively. In this study, there was a significant relationship between antibiotics (P = 0.026), cefotaxime (P = 0.003), and nalidixic acid (P = 0.044) and E. coli phylogenetic groups. No significant relationship was observed between E. coli phylogenetic groups and antibiotic resistance genes. Conclusions: The results of this study showed that strains belonging to group B2 had the highest prevalence among other phylogroups, and also, the frequency of antibiotic resistance genes and drug-resistant isolates had a higher prevalence in this phylogroup. These results show that phylogroup B2 has a more effective role in causing urinary tract infections compared to other phylogroups, and this phylogroup can be considered a genetic reservoir of antibiotic resistance.

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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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PHYLOGENETIC GROUPS AND VIRULENCE GENES OF ESCHERICHIA COLI STRAINS ISOLATED FROM THE CHILDREN GUT MICROBIOTA

Russian Clinical Laboratory Diagnostics ◽

10.18821/0869-2084-2020-65-4-251-257 ◽

2020 ◽

Vol 65 (4) ◽

pp. 251-257

Author(s):

Ludmila V. Suzhaeva ◽

Maria A. Makarova ◽

Lidiya A. Kaftyreva

Keyword(s):

Escherichia Coli ◽

Gut Microbiota ◽

Virulence Genes ◽

Intraspecific Diversity ◽

Phylogenetic Groups ◽

Phylogenetic Structure ◽

Intestinal Diseases ◽

E Coli ◽

Geographical Regions ◽

Tract Infections

Escherichia coli is characterized by a wide intraspecific diversity. The species includes both commensals and pathogens that cause diarrhea and extra-intestinal diseases. Pathogenic strains differ from non-pathogenic ones by the presence of virulence factors and their genes. The phylogenetic structure of the species is represented by four main groups (A, B1, B2, D), which differ in their prevalence among residents of different geographical regions. Pathogenic members of the species have been studied in detail, while non-pathogenic strains have not received such attention. This report presents the results of a study of 511 E. coli strains isolated from the gut microbiota of children without diarrhea and urinary tract infections, aged from 1 month to 17 years, living in St. Petersburg. The main phylogenetic groups were determined by PCR, and E. coli virulence genes associated with diarrhea and extra-intestinal diseases were identified. Results: population structure of E. coli is represented by the following groups: A-33.3%, B1-6.7%, B2-34.0%, D-26%. In the studied population 2.5% of strains belonded to EPEC and 4.5% to EAggEC. EPEC virulence genes were more often detected in strains of phylogroup B1, and EAggEC virulence genes in isolates of phylogroup D. The prevalence of extra - intestinal virulence genes was as follows: pap - 29.5%; sfa - 19.8%; afa - 3.3%; hly - 20.9%; cnf - 17.4%; aer-20.0%. The pap, sfa, hly, and cnf genes were detected mostly in the B2 phylogenetic group. Obtained data shows the similarity of E. coli phylogenetic groups structure in St. Petersburg with E. coli populations isolated from residents of Paris and Sydney. Analysis of the virulence genes prevalence showed the dependence of their presence on the genetic background bacteria.

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