Molecular characterization of antimicrobial resistance and virulence genes of Escherichia coli isolates from bovine mastitis

Background and Aim: Mastitis is a common and economically important disease in dairy cattle. It remains one of the most common reasons for the extensive use of antimicrobials in dairy farms leading to the emergence of antimicrobial-resistant pathogens. The aim of this study was to determine the patterns of antimicrobial resistance of Escherichia coli isolates from bovine mastitis and to identify prominent antimicrobial resistance and virulence genes among isolated strains. Materials and Methods: Antimicrobial susceptibility testing against six antibiotic groups, including tetracyclines, aminoglycosides, beta-lactams, macrolides, sulfonamides, and fluoroquinolones was performed using the disk diffusion method. PCR was performed on resistant isolates to detect resistance and virulence genes using commercially available primers. Results: Out of 216 milk samples cultured, 14 samples yielded E. coli isolates. All isolates (100%) were resistant to ampicillin, amoxicillin, procaine penicillin, streptomycin, oxytetracycline, and sulfamethoxazole-trimethoprim. Only one isolate (7%) was sensitive to gentamicin, and all isolates (100%) were sensitive to enrofloxacin and ciprofloxacin. All isolates carried at least one resistance gene against one or more of the major antibiotic groups. All isolates carried the ereA, tetG, tetE, and tetB genes, followed by tetA (93%), ampC (86%), strA (86%), sul1 (78%), tetD (71%), tetC (57%), aadA (57%), and strB (36%). The lowest percentage of isolates carried bla1 (17%) and bla2 (12%) genes, and none of the isolates carried the qnrA gene. Most of the isolates (93%) carried the Shiga toxin 1 virulence gene, followed by complement resistance protein (79%), intimin (64%), Shiga toxin 2 (36%), cytotoxic necrotizing factor (35%), aerotaxis receptor (21%), and type 1 fimbriae (15%). Conclusion: Results of this study indicate that the high percentages of E. coli isolate from bovine mastitis are resistant to two or more of the major antibiotic groups, irrespective of the presence or absence of relevant resistance or virulence genes.

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Molecular characterisation of antimicrobial resistance and virulence genes in Escherichia coli strains isolated from diarrhoeic and healthy rabbits in Tunisia

World Rabbit Science ◽

10.4995/wrs.2020.10879 ◽

2020 ◽

Vol 28 (2) ◽

pp. 81

Author(s):

Raouia Ben Rhouma ◽

Ahlem Jouini ◽

Amira Klibi ◽

Safa Hamrouni ◽

Aziza Boubaker ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Virulence Genes ◽

Antimicrobial Agents ◽

Antibiotic Resistance Genes ◽

Virulence Gene ◽

Diffusion Method ◽

Class 1 Integron ◽

E Coli ◽

Class 1

The purpose of this study was to identify Escherichia coli isolates in diarrhoeic and healthy rabbits in Tunisia and characterise their virulence and antibiotic resistance genes. In the 2014-2015 period, 60 faecal samples from diarrhoeic and healthy rabbits were collected from different breeding farms in Tunisia. Susceptibility to 14 antimicrobial agents was tested by disc diffusion method and the mechanisms of gene resistance were evaluated using polymerase chain reaction and sequencing methods. Forty E. coli isolates were recovered in selective media. High frequency of resistance to tetracycline (95%) was detected, followed by different levels of resistance to sulphonamide (72.5%), streptomycin (62.5%), trimethoprim-sulfamethoxazole (60%), nalidixic acid (32.5%), ampicillin (37.5%) and ticarcillin (35%). E. coli strains were susceptible to cefotaxime, ceftazidime and imipenem. Different variants of blaTEM, tet, sul genes were detected in most of the strains resistant to ampicillin, tetracycline and sulphonamide, respectively. The presence of class 1 integron was studied in 29 sulphonamide-resistant E. coli strains from which 15 harboured class 1 integron with four different arrangements of gene cassettes, dfrA17+aadA5 (n=9), dfrA1 + aadA1 (n=4), dfrA12 + addA2 (n=1), dfrA12+orf+addA2 (n=1). The qnrB gene was detected in six strains out of 13 quinolone-resistant E. coli strains. Seventeen E. coli isolates from diarrhoeic rabbits harboured the enteropathogenic eae genes associated with different virulence genes tested (fimA, cnf1, aer), and affiliated to B2 (n=8) and D (n=9) phylogroups. Isolated E. coli strains from healthy rabbit were harbouring fim A and/or cnf1 genes and affiliated to A and B1 phylogroups. This study showed that E. coli strains from the intestinal tract of rabbits are resistant to the widely prescribed antibiotics in medicine. Therefore, they constitute a reservoir of antimicrobial-resistant genes, which may play a significant role in the spread of antimicrobial resistance. In addition, the eae virulence gene seemed to be implicated in diarrhoea in breeder rabbits in Tunisia.

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Prevalence and antibiotic resistance profile of Shiga toxin-producing Escherichia coli isolated from diarrheal samples

Iranian Journal of Microbiology ◽

10.18502/ijm.v12i4.3931 ◽

2020 ◽

Author(s):

Farzad Esavand Heydari ◽

Mojtaba Bonyadian ◽

Hamdallah Moshtaghi ◽

Masoud Sami

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Shiga Toxin ◽

Virulence Genes ◽

Enterohemorrhagic Escherichia Coli ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Resistance Profile ◽

E Coli ◽

Antibiotic Resistance Profile

Background and Objectives: Enterohemorrhagic Escherichia coli (EHEC) causes bloody and non-bloody diarrhea, intestinal infection and extraintestinal complications in humans. This study aimed to isolate and evaluate the prevalence of E. coli O157: H7 and other Shiga toxin-producing E. coli (STEC) and identify the virulence genes (stx1, stx2, hly and eaeA) from patients with diarrhea. Also, the antibiotic resistance profile of the isolated strains was evaluated. Materials and Methods: A total of 100 stool samples were collected from patients with acute diarrhea referring to the hospital and clinics in Isfahan County, Iran. Phenotypic tests and PCR assay were used for detection of E. coli O157: H7 and other Shiga toxin-producing E. coli. The presence of virulence genes (stx1, stx2, hly and eaeA) were identified by PCR. The antibiotic resistance profile of the isolates was determined using the agar disk diffusion method. The results were analyzed descriptively by Sigma stat version 4 software. Results: Seventy - eight out of 100 samples (78%) were contaminated with E. coli. E. coli O157 was isolated from five samples (6.4%), of which only two strains (2.56%) were identified as E. coli O157: H7. According to the results, out of two E. coli O157: H7 isolates, one (50%) isolate contained eaeA and two isolates (100%) contained Stx1, Stx2, hlyA genes. Out of three (3.84%) E. coli O157: HN, one of the isolate (33.3%) contained stx1 and, two isolates (66.7%) were positive for hlyA genes. Also, the results revealed that six strains (7.69%) were non-O157: H7 STEC, of which two isolates (33.3%) contained stx1 and four isolates (66.7%) were positive for stx2 and hlyA genes. The results of antibiogram tests revealed that all of the STEC isolates (100%) were sensitive to imipenem followed by kanamycin, gentamicin and nitrofurantoin (91%). High resistance (54.5%) to ampicillin and ciprofloxacin was observed among the STEC isolates. Conclusion: The results of the current study showed that although the prevalence of E. coli O157: H7 was low among patients with diarrhea, the other STEC strains with relative resistance to antibiotics are more prevalent.

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Phenotypic Antimicrobial Susceptibility of Escherichia coli from Raw Meats, Ready-to-Eat Meats, and Their Related Samples in One Health Context

Microorganisms ◽

10.3390/microorganisms9020326 ◽

2021 ◽

Vol 9 (2) ◽

pp. 326

Author(s):

Frederick Adzitey ◽

Nurul Huda ◽

Amir Husni Mohd Shariff

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Antimicrobial Susceptibility ◽

Resistance Index ◽

Diffusion Method ◽

Resistant Bacteria ◽

Disk Diffusion Method ◽

E Coli ◽

The Usa ◽

Raw Meats

Meat is an important food source that can provide a significant amount of protein for human development. The occurrence of bacteria that are resistant to antimicrobials in meat poses a public health risk. This study evaluated the occurrence and antimicrobial resistance of E. coli (Escherichia coli) isolated from raw meats, ready-to-eat (RTE) meats and their related samples in Ghana. E. coli was isolated using the USA-FDA Bacteriological Analytical Manual and phenotypic antimicrobial susceptibility test was performed by the disk diffusion method. Of the 200 examined meats and their related samples, 38% were positive for E. coli. Notably, E. coli was highest in raw beef (80%) and lowest in RTE pork (0%). The 45 E. coli isolates were resistant ≥ 50% to amoxicillin, trimethoprim and tetracycline. They were susceptible to azithromycin (87.1%), chloramphenicol (81.3%), imipenem (74.8%), gentamicin (72.0%) and ciprofloxacin (69.5%). A relatively high intermediate resistance of 33.0% was observed for ceftriaxone. E. coli from raw meats, RTE meats, hands of meat sellers and working tools showed some differences and similarities in their phenotypic antimicrobial resistance patterns. Half (51.1%) of the E. coli isolates exhibited multidrug resistance. The E. coli isolates showed twenty-two different resistant patterns, with a multiple antibiotic resistance index of 0.0 to 0.7. The resistant pattern amoxicillin (A, n = 6 isolates) and amoxicillin-trimethoprim (A-TM, n = 6 isolates) were the most common. This study documents that raw meats, RTE meats and their related samples in Ghana are potential sources of antimicrobial-resistant E. coli and pose a risk for the transfer of resistant bacteria to the food chain, environment and humans.

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Molecular types, virulence profiles and antimicrobial resistance of Escherichia coli causing bovine mastitis

Veterinary Record Open ◽

10.1136/vetreco-2019-000369 ◽

2019 ◽

Vol 6 (1) ◽

pp. e000369 ◽

Cited By ~ 5

Author(s):

Magdalena Nüesch-Inderbinen ◽

Nadine Käppeli ◽

Marina Morach ◽

Corinne Eicher ◽

Sabrina Corti ◽

...

Keyword(s):

Escherichia Coli ◽

Bovine Mastitis ◽

Tetracycline Resistance ◽

Diffusion Method ◽

Sample Population ◽

Disk Diffusion Method ◽

E Coli ◽

Phylogenetic Grouping ◽

Resistance Rates ◽

Susceptibility Profiles

BackgroundEscherichia coli is an important aetiological agent of bovine mastitis worldwide.MethodsIn this study, 82 E. coli from bovine mastitis milk samples from 49 farms were analysed for their genetic diversity using phylogenetic grouping and multilocus sequence typing. The isolates were examined by PCR for a selection of virulence factors (VFs). Antimicrobial susceptibility profiles were assessed using the disk diffusion method.ResultsThe most prevalent phylogroups were group B1 (41.5 per cent of the isolates) and group A (30.5 per cent). A variety of 35 different sequence types (STs) were identified, including ST1125 (11 per cent), ST58 (9.8 per cent), ST10 (8.5 per cent) and ST88 (7.3 per cent). Aggregate VF scores (the number of unique VFs detected for each isolate) ranged from 1 to 3 for 63.4 per cent of the isolates and were at least 4 for 12.2 per cent. For 24.4 per cent of the isolates, the score was 0. The three most frequent VFs were traT, fyuA and iutA. The majority (72 per cent) of the isolates harboured traT. The majority (68.3 per cent) of the isolates were fully susceptible to all antimicrobials tested, with 22 per cent resistant to ampicillin and 14.6 per cent to tetracycline. Resistance rates were low for gentamicin (3.7 per cent), amoxicillin/clavulanic acid (2.4 per cent) and ceftiofur (1.2 per cent), respectively.ConclusionAmong the study’s sample population, E. coli strains were genotypically diverse, even in cows from the same farm, although some STs occurred more frequently than others. Susceptibility to clinically relevant compounds remained high.

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Antibiotic resistance and virulence genes of extraintestinal pathogenic Escherichia coli from tropical estuary, south India

The Journal of Infection in Developing Countries ◽

10.3855/jidc.5627 ◽

2015 ◽

Vol 9 (05) ◽

pp. 496-504 ◽

Cited By ~ 1

Author(s):

Divya Sukumaran ◽

Abdulla A Mohamed Hatha

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Multidrug Resistance ◽

Virulence Factor ◽

Virulence Genes ◽

Antimicrobial Agents ◽

Diffusion Method ◽

Disk Diffusion Method ◽

E Coli ◽

Virulence Factor Genes

Introduction: Escherichia coli strains can cause a variety of intestinal and extraintestinal diseases. Extraintestinal pathogenic E. coli (ExPEC) strains have the ability to cause severe extraintestinal infections. Multidrug resistance among ExPEC could complicate human infections. Methodology: Escherichia coli strains were isolated during the period of January 2010 to December 2012 from five different stations set at Cochin estuary. Susceptibility testing was determined by the disk-diffusion method using nine different antimicrobial agents. A total of 155 strains of Escherichia coli were screened for the presence of virulence factor genes including papAH, papC, sfa/focDE, iutA,and kpsMT II associated with ExPEC. Results: Among the 155 E. coli isolates, 26 (16.77%), carried two or more virulence genes typical of ExPEC. Furthermore, 19.23% of the ExPEC isolates with multidrug resistance were identified to belong to phylogenetic groups B2 and D. Statistically significant association of iutA gene in ExPEC was found with papC (p < 0.001) and kpsMT II (p < 0.001) genes. ExPEC isolates were mainly resistant to ampicillin (23.07%), tetracycline (19.23%), co-trimoxazole (15.38%), and cefotaxime (15.38%). The adhesion genes papAH and sfa/focDE were positively associated with resistance to gentamicin, chloramphenicol, and cefotaxime (p < 0.05). Conclusions: Co-occurrence of virulence factor genes with antibiotic resistance among ExPEC poses considerable threat to those who use this aquatic system for a living and for recreation.

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Frequency and Characterization of Antimicrobial Resistance and Virulence Genes of Coagulase-Negative Staphylococci from Wild Birds in Spain. Detection of tst-Carrying S. sciuri Isolates

Microorganisms ◽

10.3390/microorganisms8091317 ◽

2020 ◽

Vol 8 (9) ◽

pp. 1317

Author(s):

Laura Ruiz-Ripa ◽

Paula Gómez ◽

Carla Andrea Alonso ◽

María Cruz Camacho ◽

Yolanda Ramiro ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Virulence Genes ◽

Meca Gene ◽

Virulence Gene ◽

Wild Birds ◽

Diffusion Method ◽

Coagulase Negative Staphylococci ◽

Disk Diffusion Method ◽

Resistance Phenotype ◽

Antimicrobial Resistance Genes

The objective of this study was to determine the prevalence and diversity of coagulase-negative staphylococci (CoNS) species from wild birds in Spain, as well as to analyze the antimicrobial resistance phenotype/genotype and the virulence gene content. During 2015–2016, tracheal samples of 242 wild birds were collected in different regions of Spain for staphylococci recovery. The species identification was performed using MALDI-TOF. The antimicrobial resistance phenotype and genotype was investigated by the disk diffusion method and by PCR, respectively. The presence of the virulence genes lukF/S-PV, tst, eta, etb, etd and scn was investigated by PCR. Moreover, CoNS carrying the mecA gene were subjected to SCCmec typing. Of the tested animals, 60% were CoNS-carriers, and 173 CoNS isolates were recovered from the 146 positive animals, which belonged to 11 species, with predominance of S. sciuri (n = 118) and S. lentus (n = 25). A total of 34% of CoNS isolates showed a multidrug resistance phenotype, and 42 mecA-positive methicillin-resistant CoNS (MRCoNS) were detected. The isolates showed resistance to the following antimicrobials (percentage of resistant isolates/antimicrobial resistance genes detected): penicillin (49/ blaZ, mecA), cefoxitin (24/ mecA), erythromycin and/or clindamycin (92/ erm(B), erm(C), erm(43), msr(A), mph(C), lnu(A), lsa(B), vga(A) and sal(A)), gentamicin and/or tobramycin (5/ aac(6′)-Ie-aph(2″)-Ia, ant(4′)-Ia), streptomycin (12/str), tetracycline (17/ tet(K), tet(L), tet(M)), ciprofloxacin (4), chloramphenicol (1/ fexA), fusidic acid (86/ fusB, fusD) and trimethoprim–sulfamethoxazole (1/ dfrK). None of the isolates harbored the lukF/S-PV, eta, etb, etd and scn genes, but two S. sciuri isolates (1%) carried the tst gene. Wild birds are frequently colonized by CoNS species, especially S. sciuri. We identified scavenging on intensively produced livestock and feeding on landfills as risk factors for CoNS carriage. High proportions of MRCoNS and multidrug resistant CoNS were detected, which coupled with the presence of important virulence genes is of concern.

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Pathogenic features of urinary Escherichia coli strains causing Asymptomatic Bacteriuria during Pregnancy

10.21203/rs.2.22234/v1 ◽

2020 ◽

Author(s):

Samane Mohebi ◽

zahra Hashemizade ◽

Mahtab Hadadi ◽

Soudeh Kholdi ◽

Kasra Javadi ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Genes ◽

Asymptomatic Bacteriuria ◽

Urine Samples ◽

Diffusion Method ◽

Low Birth Weight Infants ◽

Phylogenetic Groups ◽

Disk Diffusion Method ◽

Cross Sectional ◽

E Coli

Abstract Background Asymptomatic bacteriuria is one of the common problems in pregnancy. Pyelonephritis, preterm labor and low birth weight infants have been associated with bacterial infection. Urinary tract infection (UTI) during pregnancy is frequently associated with complications. An observational cross-sectional study including investigated the prevalence of virulence genes, antimicrobial resistance, and its relationship with phylogenetic groups among E. coli strains isolated from pregnant women with asymptomatic bacteriuria who referred to Hafez hospital, Shiraz, Iran.Material and Methods A total of 300 urine samples were screened for Escherichia coli strains. Susceptibility testing was determined by the disk-diffusion method. The phylogenetic groups and 13 virulence genes were identified by PCR. ESBL and AmpC producing isolates were detected using phenotypic methods. PCR was used to identify the bla TEM , bla SHV and bla CTXM genes in ESBL and AmpC-positive isolates.Results Our results revealed that among 300 urine samples, 105 (35%) were positive for E. coli . The data showed that the highest and the lowest resistance rates were observed against nalidixic acid (82.1%), and imipenem (2.8%), respectively. The prevalence of ESBLs and AmpC-β-lactamase, in the E. coli isolates was 41% and 9.5% respectively. bla CTXM was the commonest genotype (93%). Phylogenetic group distribution was as follow: B1 2.8%, A 14.2%, B2 61.9%, and D 4.6%. Our result showed that most of the virulence genes belonged to group B2 and also several virulence genes such as hlyA , cnf-1 , and papGII genes were positively associated with group B2. Conclusion Among E. coli strains isolated from patients with UTIs, different features phylogroups, with special virulence factors, could cause severe infection. Awareness about the Virulence patterns distribution among Phylogenetic groups of UPEC could greatly aid in confine and prevent the development of lethal infection caused by these strains.

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Prevalence of Shiga toxin-producing Escherichia coli isolated from chicken meat in west of Iran

10.21203/rs.2.11448/v1 ◽

2019 ◽

Author(s):

omid zarei ◽

Leili Shokoohizadeh ◽

Hadi Hossainpour ◽

Mohammad Yousef Alikhani

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Genetic Relatedness ◽

Culture Media ◽

Chicken Meat ◽

Diffusion Method ◽

Disk Diffusion Method ◽

E Coli ◽

Meat Samples ◽

High Level

Abstract Objective: Shiga toxin producing Escherichia coli (STEC) has known as a crucial zoonotic food borne pathogen. A total of 257 row chicken meat samples were collected from different markets in Hamadan city from January 2016 to May 2017. Samples were cultured on selective and differential culture media, and the virulence genes of E. coli isolates were analyzed by PCR assay. The antibiotic resistance patterns of E. coli isolates were determined by disk diffusion method. The genetic relatedness of STEC isolates were analyzed by ERIC-PCR. Results: Totally, 93(36%) of isolates were identified as E. coli in this current study. According serological and microbiological tests, 5(5.3%), 31(33.3%) and 7(7.5%) of E. coli isolates, characterized as Enterohemorrhagic E. coli (EHEC), STEC and attaching and effacing E. coli (AEEC) strains, respectively. High level resistance to tetracycline (89.8), ampicillin (82.8%) and sulfametoxazole-trimotoprime (71%) were detected among E. coli isolates. Analysis of ERIC-PCR results showed five different ERIC types among EHEC isolates. Based on our findings, chicken meat identified as a sources of STEC strains, therefore, the controlling and checkup the chicken meats for the resistance and virulent strains of E. coli should be consider as a crucial issues in public health.

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Distribution of Serotypes, Antimicrobial Resistance and Virulence Genes among Streptococcus agalactiae Isolated from Bovine in China

Acta Scientiae Veterinariae ◽

10.22456/1679-9216.97254 ◽

2019 ◽

Vol 47 (1) ◽

Author(s):

Zhe Zhang ◽

Feng Yang ◽

Xin-pu Li ◽

Jin-yin Luo ◽

Long-hai Liu ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Resistance ◽

Streptococcus Agalactiae ◽

Significant Interaction ◽

Virulence Genes ◽

Bovine Mastitis ◽

Diffusion Method ◽

Economic Losses ◽

And Staphylococcus Aureus

Background: Bovine mastitis, a global disease that is responsible for large economic losses each year due to lower milk yield and reduced milk quality. In some countries, especially in China, Streptococcus agalactiae has become one of the most frequently detected pathogen. Antibiotic treatment and vaccine immunization are important strategies for the control of infectious diseases. The main objective of the present study was to evaluate distribution of bovine mastitis pathogens and antimicrobial resistance of S. agalactiae, and contribute to the treatment of bovine mastitis.Materials, Methods & Results:Clinical mastitis samples (n= 1,122) were collected from 27 dairy farms located in 15 different provinces of China during 2012-2018. Thepathogens were identified by 16S rDNA method. Antimicrobial susceptibility was assessed by disc diffusion method. Molecular characteristics was distinguished based on PCR. The results showed that the main pathogens were Streptococcus agalactiae (n= 324, 26.2%), Escherichia coli (n= 287, 23.2%), and Staphylococcus aureus (n= 131, 10.6%). The serotypes of Streptococcus agalactiae were serotype II (53.6%), Ia (44 %) and VII (1.2%), respectively. Streptococcus agalactiae were resistant to kanamycin (93.8%), gentamicin (49.4%), vancomycin (49.4%), tetracycline (35.8%), clindamycin (34.6%) and erythromycin (32.1%). The main resistance genes were ermA (53.1%) and ermB (85.2%). Resistance to erythromycin was attributed to the genes ermA (P < 0.05) and resistance to tetracycline was attributed to the genes tetK, tetM, tetO (P < 0.01). The virulence genes scpB (81.4%), cyl (100%), glnA (76.6%), cfb (98.8%), hylB (98.8%), scaA (69.1%) were detected in almost all isolates.Discussion: In the present study, Streptococcus agalactiae, Escherichia coli and Staphylococcus aureus were the pathogens isolated most frequently from clinical mastitis. In the case of S. agalactiae, we performed capsular serotyping of isolates. As a result, serotype II (53.6%), Ia (44 %) and VII (1.2%) were detected whichrevealed variation in the distinct geographical areas. We found that serotypes (Ia and II) and β-hemolytic have significant correlation (P < 0.01) in all isolated strains. We made an assumption that either in processes of capsular and haemolytic appearance effected the expression of another. The unclear mechanism remains to be resolved in the future. Penicillin was recommended as a preferred antibiotic for the treatment of both human and bovine S. agalactiae infection. In the present study, resistance to erythromycin and clindamycin were observed in 32% and 34.6% of our strains, respectively. The results indicated that the ermB gene was most frequent among the erythromycin-resistant S. agalactiae. However, we found that the susceptibility to erythromycin and gene ermA have a significant interaction, while susceptibility to erythromycin and gene ermB have a not significant interaction by analyzing the relationship of phenotypic and genotypic resistance. The severity of S. agalactiae infections may be determined by various virulence factors. Surface enzyme ScpB, a C5a peptidase, encode by scpB gene, could promote bacterial invasion of epithelial cells by attenuating recruitment of polymorphonuclear leukocytes to the site of infection. In the present study, the scpB gene was found in 81.4% of all strains. The results suggested the cyl, cfb, hylB and scpB genes may play an important role in the virulence of Streptococcus agalactiae pathogens.

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Pathogenic features of urinary Escherichia coli strains causing Asymptomatic Bacteriuria during Pregnancy

10.21203/rs.2.22234/v2 ◽

2020 ◽

Author(s):

Samane Mohebi ◽

zahra Hashemizade ◽

Mahtab Hadadi ◽

Soudeh Kholdi ◽

Kasra Javadi ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Genes ◽

Asymptomatic Bacteriuria ◽

Urine Samples ◽

Diffusion Method ◽

Low Birth Weight Infants ◽

Phylogenetic Groups ◽

Disk Diffusion Method ◽

Cross Sectional ◽

E Coli

Abstract Background Asymptomatic bacteriuria is one of the common problems in pregnancy. Pyelonephritis, preterm labor and low birth weight infants have been associated with bacterial infection. Urinary tract infection (UTI) during pregnancy is frequently associated with complications. An observational cross-sectional study including investigated the prevalence of virulence genes, antimicrobial resistance, and its relationship with phylogenetic groups among E. coli strains isolated from pregnant women with asymptomatic bacteriuria who referred to Hafez hospital, Shiraz, Iran. Material and Methods A total of 300 urine samples were screened for Escherichia coli strains. Susceptibility testing was determined by the disk-diffusion method. The phylogenetic groups and 13 virulence genes were identified by PCR. ESBL and AmpC producing isolates were detected using phenotypic methods. PCR was used to identify the bla TEM , bla SHV and bla CTXM genes in ESBL and AmpC-positive isolates. Results Our results revealed that among 300 urine samples, 105 (35%) were positive for E. coli . The data showed that the highest and the lowest resistance rates were observed against nalidixic acid (82.1%), and imipenem (2.8%), respectively. The prevalence of ESBLs and AmpC-β-lactamase, in the E. coli isolates was 41% and 9.5% respectively. bla CTXM was the commonest genotype (93%). Phylogenetic group distribution was as follow: B1 2.8%, A 14.2%, B2 61.9%, and D 4.6%. Our result showed that most of the virulence genes belonged to group B2 and also several virulence genes such as hlyA , cnf-1 , and papGII genes were positively associated with group B2. Conclusion Among E. coli strains isolated from patients with UTIs, different features phylogroups, with special virulence factors, could cause severe infection. Awareness about the Virulence patterns distribution among Phylogenetic groups of UPEC could greatly aid in confine and prevent the development of lethal infection caused by these strains.

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