Virulence Characteristics and Antibiotic Resistance Profiles of Shiga Toxin-Producing Escherichia coli Isolates from Diverse Sources

Shiga toxin-producing Escherichia coli (STEC) is an enteric pathogen that causes several gastrointestinal ailments in humans across the world. STEC’s ability to cause ailment is attributed to the presence of a broad range of known and putative virulence factors (VFs) including those that encode Shiga toxins. A total of 51 E. coli strains belonging to serogroups O26, O45, O103, O104, O113, O121, O145, and O157 were tested for the presence of nine VFs via PCR and for their susceptibility to 17 frequently used antibiotics using the disc diffusion method. The isolates belonged to eight different serotypes, including eight O serogroups and 12 H types. The frequency of the presence of key VFs were stx1 (76.47%), stx2 (86.27%), eae (100%), ehxA (98.03%), nleA (100%), ureC (94.11%), iha (96.07%), subA (9.80%), and saa (94.11%) in the E. coli strains. All E. coli strains carried seven or more distinct VFs and, among these, four isolates harbored all tested VFs. In addition, all E. coli strains had a high degree of antibiotic resistance and were multidrug resistant (MDR). These results show a high incidence frequency of VFs and heterogeneity of VFs and MDR profiles of E. coli strains. Moreover, half of the E. coli isolates (74.5%) were resistant to > 9 classes of antibiotics (more than 50% of the tested antibiotics). Thus, our findings highlight the importance of appropriate epidemiological and microbiological surveillance and control measures to prevent STEC disease in humans worldwide.

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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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Resistensi Antibiotik pada Escherichia coli yang Diisolasi dari Daging Ayam pada Pasar Tradisional di Kota Bogor (ANTIBIOTIC RESISTANCE IN ESCHERICHIA COLI ISOLATED FROM CHICKEN MEAT OF TRADITIONAL MARKETS IN THE CITY OF BOGOR)

jurnal veteriner ◽

10.19087/jveteriner.2019.20.1.125 ◽

2019 ◽

Vol 20 (1) ◽

pp. 125

Author(s):

Connie Januari ◽

Mirnawati Bachrum Sudarwanto ◽

Trioso Purnawarman

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Bacterial Resistance ◽

Antibiotic Use ◽

Multidrug Resistant ◽

Chicken Meat ◽

Diffusion Method ◽

Negative Effects ◽

Disk Diffusion Method ◽

E Coli

Antibiotic use in farm is spread widely to treat of poultry disease including therapy, supportive or preventive use and as afeed additive to improve chicken performance. The negative effects of antibiotic use can increase the level of bacterial resistance to antibiotics. This study aimed to investigate on antibiotic resistance in Escherichia coli isolated from chicken meat that were sold in Traditional Market of Bogor City. A total of 175 samples of chicken meat were taken by purposive sampling method, out of 175 found 50 positive samples of E. coli. The samples were subjected to E. coli examination and the isolated E. coli were tested for the antibiotic resistance using eight antibiotics, i.e., amoxicillin, cefotaxime, colistin, nalidixid acid, streptomycin, erythromycin, oxytetracillin, and tetracycline. The study was conducted by using the disk diffusion method on Muller-Hinton agar according to the Clinical and Laboratory Standards Institute guidelines. The study showed E. coli isolated from chicken meat were resistance towards amoxicilin (90%), colistin (94%), nalidixid acid (86%), streptomycin (98%), erythromycin (98%), oxytetracillin (84%), tetracycline (86%), and cefotaxime antibiotics (12%). The proportion of multidrugresistant was 99%. The higher of multidrug-resistant indicated the E. coli would be a threat to public and environmental health.

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Virulence Factors and Antibiotic Resistance of Escherichia coli O157:H7 Isolated from Ogun River, Abeokuta Metropolis, Nigeria

Applied Environmental Research ◽

10.35762/aer.2019.41.1.3 ◽

2019 ◽

pp. 22-30

Author(s):

Lateefat M. Ewuoso ◽

Saka A. Balogun ◽

Sarafadeen O. Kareem ◽

Temilade F. Akinhanmi

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Virulence Factors ◽

Shiga Toxin ◽

Latex Agglutination ◽

Diffusion Method ◽

Pcr Analysis ◽

E Coli ◽

Multiple Drugs ◽

Ogun River

Although Escherichia coli (E. coli)is a harmless gut microbe in man, some strains of this bacterium are pathogenic due to the acquisition of virulence factors. The aim of this study isto investigate E. coli O157:H7 strains isolated from Ogun River, Abeokuta metropolis, for virulence factors and antibiotic resistance. Water samples were collected bimonthly from six different locations over a period of six months. The samples were cultured on Sorbitol MacConkey Agar and E. coli O157:H7 isolates were confirmed through serological characterization using the latex agglutination test. The presence of virulence genes (stx1, stx2, eae, and hylA) in the isolates was analyzed through polymerase chain reaction (PCR). Further, antibiotic susceptibility of the isolates was tested using the disc diffusion method. The PCR analysis revealed that the five E. coli O157:H7 strains isolated possessed Shiga toxin 1 (stx1), Shiga toxin 2 (stx2), and Haemolysin (hlyA) genes. Additionally, the isolates were resistant to Augmentin, Ceftriaxone, Nitrofurantoin, Gentamycin, Amoxicillin, and Pefloxacin. This study shows that E. coli O157:H7 strains are present in Ogun River and that these strains possess multiple virulence factors and are resistant to multiple drugs.

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Antibiotic Resistance of Uropathogens Isolated from Patients Hospitalized in District Hospital in Central Poland in 2020

Antibiotics ◽

10.3390/antibiotics10040447 ◽

2021 ◽

Vol 10 (4) ◽

pp. 447

Author(s):

Barbara Kot ◽

Agata Grużewska ◽

Piotr Szweda ◽

Jolanta Wicha ◽

Urszula Parulska

Keyword(s):

Antibiotic Resistance ◽

Multidrug Resistant ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Beta Lactamases ◽

E Coli ◽

Central Poland ◽

Resistance Patterns ◽

Extended Spectrum Beta Lactamases ◽

Tract Infections

The aim of this study was to determine antibiotic resistance patterns and the prevalence of uropathogenes causing urinary tract infections (UTIs) in patients hospitalized in January–June 2020 in central Poland. Antimicrobial susceptibility testing was performed using the disk-diffusion method. Escherichia coli (52.2%), Klebsiella pneumoniae (13.7%), Enterococcus faecalis (9.3%), E. faecium (6.2%), and Proteus mirabilis (4,3%) were most commonly isolated from urine samples. E. coli was significantly more frequent in women (58.6%) (p = 0.0089) and in the age group 0–18, while K. pneumoniae was more frequent in men (24.4%) (p = 0.0119) and in individuals aged 40–60 and >60. Gram-negative species showed resistance to ampicillin. K. pneumoniae were resistant to amoxicillin plus clavulanic acid (75.0%), piperacillin plus tazobactam (76.2%), cefotaxime (76.2%), cefuroxime (81.0%), ciprofloxacin (81.0%), and trimethoprim plus sulphamethoxazole (81.0%). Carbapenems were effective against all E. coli and P. mirabilis. Some K. pneumoniae (13.6%) produced metallo-β-lactamases (MBLs). E. coli (22.6%), K. pneumoniae (81.8%), and all E. faecium were multidrug-resistant (MDR). Some E. coli (26.2%), K. pneumoniae (63.6%), and P. mirabilis (14.3%) isolates produced extended-spectrum beta-lactamases (ESBL). Vancomycin-resistant E. faecium was also found. This study showed that the possibilities of UTIs therapy using available antibiotics become limited due to the increasing number of antibiotic-resistant uropathogens.

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EVALUATION OF THE IMPACT OF PLASMID CURING ON ANTIBIOTIC RESISTANCE ON SOME CLINICAL ISOLATES OF ESCHERICHIA COLI

FUDMA Journal of Sciences ◽

10.33003/fjs-2020-0403-335 ◽

2020 ◽

Vol 4 (3) ◽

pp. 323-327

Author(s):

Mamunu Abdulkadir SULAIMAN ◽

H.S Muhammad ◽

Aliyu Muhammad Sani ◽

Aminu Ibrahim ◽

Ibrahim Muhammad Hussain ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Clinical Isolates ◽

Diffusion Method ◽

Plasmid Curing ◽

Sensitivity Testing ◽

E Coli ◽

Risk Of Death ◽

Mar Index ◽

The Impact

Multidrug resistance (MDR) exhibited by some strains of Escherichia coli may be due to acquiring mobile genetic element (R-plasmid) by the bacteria, or intrinsically induced by inappropriate use of antibiotics by the hosts. Infection by such strains may result to prolonged illness and greater risk of death. The study evaluated the impact of curing on antibiotic resistance on selected clinical isolates of E. coli. Twenty clinical isolates of E. coli from our previous studies were re-characterized using conventional microbiological techniques. Antibiotic sensitivity testing was determined by disk diffusion method, MDR selected based on resistance to ≥ 2 classes of antibiotics. Multiple antibiotic resistance (MAR) index was determined as ratio of the number of antibiotic resisted to the total number of antibiotics tested and considered significant if ≥. 0.2. The isolates that showed significant MAR index were subjected to plasmid curing using acridine orange, thereafter, profiled for plasmid and the cured ones were re-tested against the antibiotics they initially resisted. Out of the 20 isolates, 19 (95%) were confirmed as E. coli, all (100%) of which were MDRs, which was highest against augmentin (78.9%) followed by amoxacillin (52.6%). However, after the plasmid curing only 6 (31.6%) out of the 19 isolates cured retained significant MAR index and the level of the significance had reduced drastically in 16 (84.2%) isolates. Conclusively, curing assay can completely eliminate R-plasmid acquired resistance. More studied on plasmid curing agents for possible augmentation of the agents into antibiotics may see the rise of successful antibiotic era again.

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A Preliminary Study: Antibiotic Resistance Patterns of Escherichia coli and Enterococcus Species from Wildlife Species Subjected to Supplementary Feeding on Various South African Farms

Animals ◽

10.3390/ani10030396 ◽

2020 ◽

Vol 10 (3) ◽

pp. 396 ◽

Cited By ~ 1

Author(s):

Michaela Sannettha van den Honert ◽

Pieter Andries Gouws ◽

Louwrens Christiaan Hoffman

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Supplementary Feeding ◽

Health Concern ◽

Diffusion Method ◽

Disk Diffusion Method ◽

E Coli ◽

Wildlife Species ◽

Human Contact ◽

Resistance Patterns

Studies have shown that antibiotic resistance among wild animals is becoming a public health concern, owing to increased contact and co-habitation with domestic animals that, in turn, results in increased human contact, indirectly and directly. This type of farming practice intensifies the likelihood of antibiotic resistant traits in microorganisms transferring between ecosystems which are linked via various transfer vectors, such as rivers and birds. This study aimed to determine whether the practice of wildlife supplementary feeding could have an influence on the antibiotic resistance of the bacteria harboured by the supplementary fed wildlife, and thus play a potential role in the dissemination of antibiotic resistance throughout nature. Escherichia coli and Enterococcus were isolated from the faeces of various wildlife species from seven different farms across South Africa. The Kirby-Bauer disk diffusion method was used according to the Clinical and Laboratory Standards Institute 2018 guidelines. The E. coli (F: 57%; N = 75% susceptible) and Enterococcus (F: 67%; N = 78% susceptible) isolates from the supplementary fed (F) wildlife were in general, found to be more frequently resistant to the selection of antibiotics than from those which were not supplementary fed (N), particularly towards tetracycline (E. coli F: 56%; N: 71%/Enterococcus F: 53%; N: 89% susceptible), ampicillin (F: 82%; N = 95% susceptible) and sulphafurazole (F: 68%; N = 98% susceptible). Interestingly, high resistance towards streptomycin was observed in the bacteria from both the supplementary fed (7% susceptible) and non-supplementary fed (6% susceptible) wildlife isolates. No resistance was found towards chloramphenicol and ceftazidime.

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Cockroaches as a Source of High Bacterial Pathogens with Multidrug Resistant Strains in Gondar Town, Ethiopia

BioMed Research International ◽

10.1155/2016/2825056 ◽

2016 ◽

Vol 2016 ◽

pp. 1-6 ◽

Cited By ~ 13

Author(s):

Feleke Moges ◽

Setegn Eshetie ◽

Mengistu Endris ◽

Kahsay Huruy ◽

Dagnachew Muluye ◽

...

Keyword(s):

Bacterial Infections ◽

Bacterial Species ◽

Multidrug Resistant ◽

Resistance Rate ◽

Control Measures ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Gondar Town ◽

Resistant Strains ◽

And Control

Background. Cockroaches are source of bacterial infections and this study was aimed to assess bacterial isolates and their antimicrobial profiles from cockroaches in Gondar town, Ethiopia.Methods. A total of 60 cockroaches were collected from March 1 to May 30, 2014, in Gondar town. Bacterial species were isolated from external and internal parts of cockroaches. Disk diffusion method was used to determine antibiotic susceptibility patterns. Data were entered and analyzed by using SPSS version 20;Pvalues <0.005 were considered as statistically significant.Results. Of 181 identified bacteria species, 110 (60.8%) and 71 (39.2%) were identified from external and internal parts of cockroaches, respectively.Klebsiella pneumoniae32 (17.7%),Escherichia coli29 (16%), andCitrobacterspp. 27 (15%) were the predominant isolates. High resistance rate was observed to cotrimoxazole, 60 (33.1%), and least resistance rate was noted to ciprofloxacin, 2 (1.1%). Additionally, 116 (64.1%) of the isolates were MDR strains;Salmonellaspp. were the leading MDR isolates (100%) followed byEnterobacter(90.5%) andShigellaspp. (76.9%).Conclusion. Cockroaches are the potential source of bacteria pathogens with multidrug resistant strains and hence effective preventive and control measures are required to minimize cockroach related infections.

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Detection of biofilm among uropathogenic Escherichia coli and its correlation with antibiotic resistance pattern

Journal of Laboratory Physicians ◽

10.4103/jlp.jlp_98_18 ◽

2019 ◽

Vol 11 (01) ◽

pp. 017-022 ◽

Cited By ~ 5

Author(s):

Rashmi M. Karigoudar ◽

Mahesh H. Karigoudar ◽

Sanjay M. Wavare ◽

Smita S. Mangalgi

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Biofilm Formation ◽

Agar Plate ◽

Diffusion Method ◽

Resistance Pattern ◽

Susceptibility Pattern ◽

Sensitivity Testing ◽

E Coli ◽

Tract Infections

Abstract BACKGROUND: Escherichia coli accounts for 70%–95% of urinary tract infections (UTIs). UTI is a serious health problem with respect to antibiotic resistance and biofilms formation being the prime cause for the antibiotic resistance. Biofilm can restrict the diffusion of substances and binding of antimicrobials. In this context, the present study is aimed to perform in vitro detection of biofilm formation among E. coli strains isolated from urine and to correlate their susceptibility pattern with biofilm formation. MATERIALS AND METHODS: A total of 100 E. coli strains isolated from patients suffering from UTI were included in the study. The identification of E. coli was performed by colony morphology, Gram staining, and standard biochemical tests. The detection of biofilm was carried out by Congo Red Agar (CRA) method, tube method (TM), and tissue culture plate (TCP) method. Antimicrobial sensitivity testing was performed by Kirby–Bauer disc diffusion method on Muller–Hinton agar plate. RESULTS: Of the 100 E. coli strains, 49 (49%) and 51 (51%) were from catheterized and noncatheterized patients, respectively. Biofilm production was positive by CRA, TM, and TCP method were 49 (49%), 55 (55%), and 69 (69%), respectively. Biofilm producers showed maximum resistance to co-trimoxazole (73.9%), gentamicin (94.2%), and imipenem (11.6%) when compared to nonbiofilm producers. Significant association was seen between resistance to antibiotic and biofilm formation with a P = 0.01 (<0.05). CONCLUSION: A greater understanding of biofilm detection in E. coli will help in the development of newer and more effective treatment. The detection of biofilm formation and antibiotic susceptibility pattern helps in choosing the correct antibiotic therapy.

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Antibiotic Resistance Profile of Commensal Escherichia coli Isolated from Broiler Chickens in Qatar

Journal of Food Protection ◽

10.4315/0362-028x.jfp-17-191 ◽

2017 ◽

Vol 81 (2) ◽

pp. 302-307 ◽

Cited By ~ 13

Author(s):

Nahla O. Eltai ◽

Elmoubasher A. Abdfarag ◽

Hamad Al-Romaihi ◽

Eman Wehedy ◽

Mahmoud H. Mahmoud ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Broiler Chickens ◽

Susceptibility Testing ◽

Multidrug Resistant ◽

Test Method ◽

Health Concern ◽

E Coli ◽

Extended Spectrum ◽

Stewardship Program

ABSTRACT Antibiotic resistance (AR) is a growing public health concern worldwide, and it is a top health challenge in the 21st century. AR among Enterobacteriaceae is rapidly increasing, especially in third-generation cephalosporins and carbapenems. Further, strains carrying mobilized colistin resistance (mcr) genes 1 and 2 have been isolated from humans, food-producing animals, and the environment. The uncontrolled use of antibiotics in food-producing animals is a major factor in the generation and spread of AR. No studies have been done to evaluate AR in the veterinary sector of Qatar. This study aimed at establishing primary baseline data for the prevalence of AR among food-producing animals in Qatar. Fecal samples (172) were obtained from two broiler farms and one live bird market in Qatar, and 90 commensal Escherichia coli bacteria were isolated and subjected to susceptibility testing against 16 clinically relevant antibiotics by using the E-test method. The results found that 81 (90%) of 90 isolates were resistant to at least one antibiotic, 14 (15.5%) of 90 isolates were colistin resistant, 2 (2.2%) of 90 isolates were extended-spectrum β-lactamase producers, and 2 (2.2%) of 90 isolates were multidrug resistant to four antibiotic classes. Extended-spectrum β-lactamase–producing E. coli and colistin-resistant isolates were confirmed by using double-disc susceptibility testing and PCR, respectively. Such a high prevalence of antibiotic-resistant E. coli could be the result of a long application of antibiotic treatment, and it is an indicator of the antibiotic load in food-producing animals in Qatar. Pathogens carrying AR can be easily transmitted to humans through consumption of undercooked food or noncompliance with hygiene practices, mandating prompt development and implementation of a stewardship program to control and monitor the use of antibiotics in the community and agriculture.

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Shiga Toxin Gene Loss and Transfer In Vitro and In Vivo during Enterohemorrhagic Escherichia coli O26 Infection in Humans

Applied and Environmental Microbiology ◽

10.1128/aem.02937-06 ◽

2007 ◽

Vol 73 (10) ◽

pp. 3144-3150 ◽

Cited By ~ 140

Author(s):

Martina Bielaszewska ◽

Rita Prager ◽

Robin Köck ◽

Alexander Mellmann ◽

Wenlan Zhang ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Gene Loss ◽

Pulsed Field Gel Electrophoresis ◽

Enterohemorrhagic Escherichia Coli ◽

Toxin Gene ◽

Shiga Toxins ◽

E Coli

ABSTRACT Escherichia coli serogroup O26 consists of enterohemorrhagic E. coli (EHEC) and atypical enteropathogenic E. coli (aEPEC). The former produces Shiga toxins (Stx), major determinants of EHEC pathogenicity, encoded by bacteriophages; the latter is Stx negative. We have isolated EHEC O26 from patient stools early in illness and aEPEC O26 from stools later in illness, and vice versa. Intrapatient EHEC and aEPEC isolates had quite similar pulsed-field gel electrophoresis (PFGE) patterns, suggesting that they might have arisen by conversion between the EHEC and aEPEC pathotypes during infection. To test this hypothesis, we asked whether EHEC O26 can lose stx genes and whether aEPEC O26 can be lysogenized with Stx-encoding phages from EHEC O26 in vitro. The stx 2 loss associated with the loss of Stx2-encoding phages occurred in 10% to 14% of colonies tested. Conversely, Stx2- and, to a lesser extent, Stx1-encoding bacteriophages from EHEC O26 lysogenized aEPEC O26 isolates, converting them to EHEC strains. In the lysogens and EHEC O26 donors, Stx2-converting bacteriophages integrated in yecE or wrbA. The loss and gain of Stx-converting bacteriophages diversifies PFGE patterns; this parallels findings of similar but not identical PFGE patterns in the intrapatient EHEC and aEPEC O26 isolates. EHEC O26 and aEPEC O26 thus exist as a dynamic system whose members undergo ephemeral interconversions via loss and gain of Stx-encoding phages to yield different pathotypes. The suggested occurrence of this process in the human intestine has diagnostic, clinical, epidemiological, and evolutionary implications.

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