Diarrheagenic Escherichia Coli Strains Research Articles

Animal-originated foods as Potential sources of multidrug-resistant diarrheagenic E. coli Pathotypes in Kayseri, Türkiye

This study aims to determine the prevalence and antibiotic resistance profile of diarrheagenic Escherichia coli (DEC) pathotypes from a total of 300 cattle-derived food samples, including 50 raw milk, 50 cheese, 25 yogurt, 25 meatballs, 50 minced meat, 50 cubed meat, 25 sausages, and 25 pastirma. DEC pathotypes were detected by amplification of pathotype-specific virulence genes with PCR and the antimicrobial resistance profile of isolates was assessed by the disc diffusion method. E. coli was found to be positive in 215 of the analyzed samples, of which 55 (26%) were identified as DEC. The highest DEC prevalence was observed in cubed meat (40%), followed by meatballs (36%), sausage (32%), minced meat (28%), and cheese (8%). The most frequently identified DEC pathotype was EIEC (45.4%), followed by ETEC (23.6%), EPEC (20%), DAEC (7.2%), and STEC O157 (3.6%). Of the DEC strains, 52.7% displayed resistance to at least two antibiotics. Among them, 26 (89.6%) were identified as multidrug-resistant (MDR) with a multiple antibiotic resistance (MAR) index greater than 0.2. These findings suggest that the samples likely originated from sources where frequent antibiotic usage is common, posing a significant risk. This study revealed that the prevalence of MDR-DECs in the analyzed animal-originated food products might pose a serious public health concern due to the potential transmission of resistant bacteria and resistance genes to humans through the food chain.

Virulence genes, antimicrobial resistance profile, phylotyping and pathotyping of diarrheagenic Escherichia coli isolated from children in Southwest Mexico.

Diarrheagenic E. coli (DEC) strains are one of the most important etiology factors causing diarrhea in children worldwide, especially in developing countries. DEC strains have characteristic virulence factors; however, other supplemental virulence genes (SVG) may contribute to the development of diarrhea in children. Therefore, this study aimed to determine the prevalence of DEC in children with diarrhea in southwestern Mexico and to associate childhood symptoms, SVG, and pathotypes with diarrhea-causing DEC strains. DEC strains were isolated from 230 children with diarrhea aged 0-60 months from the state of Oaxaca, southwestern Mexico; clinical data were collected, and PCR was used to identify SVG and pathotypes. Antibiotic resistance profiling was performed on DEC strains. 63% of samples were DEC positive, single or combined infections (two (21%) or three strains (1.3%)) of aEPEC (51%), EAEC (10.2%), tEPEC (5.4%), DAEC (4.8%), ETEC (4.1%), EIEC (1.4%), or EHEC (0.7%) were found. Children aged ≤ 12 and 49-60 months and symptoms (e.g., fever and blood) were associated with DEC strains. SVG related to colonization (nleB-EHEC), cytotoxicity (sat-DAEC and espC-tEPEC), and proteolysis (pic-aEPEC) were associated with DECs strains. E. coli phylogroup A was the most frequent, and some pathotypes (aEPEC-A, DAEC-B), and SVG (espC-B2, and sat-D) were associated with the phylogroups. Over 79% of the DEC strains were resistant to antibiotics, and 40% were MDR and XDR, respectively. In conclusion aEPEC was the most prevalent pathotype in children with diarrhea in this region. SVG related to colonization, cytotoxicity, and proteolysis were associated with diarrhea-producing DEC strains, which may play an essential role in the development of diarrhea in children in southwestern Mexico.

Antimicrobial Susceptibility Profiles of Diarrheagenic Escherichia coli Strains Isolated in Children Below Five Years and Food Animals Kisumu County, Kenya

Background: Diarrheagenic Escherichia coli (DEC) are the major cause of diarrhoea in children in developing and undeveloped countries. Domestic food animals act as reservoirs of DEC that are transmitted to children below five years through inadequate hygiene practices. Aim: To determine the antimicrobial susceptibility patterns of DEC strains isolated from children below five years and food animals in Kisumu County. Methods: A total of 250 samples, were collected and analyzed using polymerase chain reaction. The antimicrobial susceptibility was determined using Kirby-Bauer disc diffusion method. Results: Enteroaggregative E.coli (12%), Enteropathogenic E.coli (5%), Enterotoxigenic E.coli (3%) and mixed infections (3%) respectively. From the DEC children sample isolates, antimicrobial agents showed 84.6% sensitivity towards Meropenem followed by Gentamicin (80.8%) and then Nalidixic acid (73.1%). High resistance was recorded among the Tetracycline and Sulfamethoxazole antibiotics. Of the 26 DEC children sample isolates, 24(92%) exhibited multidrug resistance patterns: 46% showed resistance to four different antibiotics, 38% to five different antibiotics and 4% to six different antibiotics. Animal samples showed 100% susceptibility to most antibiotics, with only two isolates showing multidrug resistance to five antibiotics and one showing resistance to four and three antibiotics, respectively. The multidrug index value for the DEC pathotypes isolated in children was 0.5, indicating a high risk of DEC transmission.

Features of <i>ESCHERICHIA COLI</i> samples from patients with diarrheal syndrome in the Republic of Guinea

Introduction. Diarrheal diseases are a global public health issue and cause 15% of deaths in children under 5 years old, of which about 80% occur in the regions of Africa and Southeast Asia. According to the Global Enteric Multicentre Study (GEMS) conducted in a number of African countries, one of the leading pathogens of high risk of death in infants and young children is diarrheagenic E. coli (DEC). In recent decades, antimicrobial resistance (AMR) has become globally ubiquitous. The Republic of Guinea urgently needs large-scale studies devoted to assessing DEC distribution and antibiotic resistance. The purpose of the study is to assess the pattern of E. coli infections and to test the susceptibility to antibiotics in strains of diarrheagenic E. coli sampled from individuals residing in the Republic of Guinea.
 Materials and methods. From 2019 to 2022, we studied 724 samples of faeces of patients with acute diarrhea, among them 72 (9.9%) children aged 1–5 years, 128 (17.7%) children aged 6–17 years, and 524 (72.4%) people aged 18 years and older; a method of polymerase chain reaction (PCR) was applied with the use of the AmpliSense® Escherichioses-FL reagent kit to identify the genetic determinants of DEC: EPEC, EHEC, ETEC, EIEC, and EAgEC (Central Research Institute of Epidemiology of Rospotrebnadzor, Russia). Susceptibility to 15 antimicrobial agents was found by the disc-diffusion method using Mueller–Hinton agar (Russia) and Oxoid discs (UK). Results were interpreted according EUCAST criteria, versions 2019–2022 (https://www.eucast.org/ast_of_bacteria/previous_versions_of_documents).
 Results. For the period from 2019 to 2022, the percentage of E. coli infections in the etiological pattern of acute intestinal infections amounted to 51.7%. In the age-related manner, DEC was significantly more common in young children aged 0–5 (96.9%, p 0.05) as compared to school age children aged 6–17 (53.9%) and adults (45.6%). In all years of observation, EAgEC strains prevailed, accounting for 38.4%. Other DEC pathotypes, EPEC, ETEC, EIEC and STEC, accounted for 27.2%, 17.5%, 11.8%, and 5.1%, respectively. DEC strains are susceptible to meropenem, amikacin, and nitrofurantoin. The activity of other antibiotics ranged from 11.3% for ampicillin, 28.3% for trimethoprim-sulfamethoxazole, and 34.0% for tetracycline to 73.6% for cephalosporins, 84.0% for aminoglycosides, and 98.1% for fluorinated quinolones.
 Conclusion. To reduce the burden of diarrheal diseases in the Republic of Guinea, it may be necessary to conduct targeted epidemiological and microbiological studies to identify DEC and monitor the development of antimicrobial resistance of E. coli infection pathogens in the population.

Detection of Some Virulence Genes in Diarrheagenic Escherichia Coli Pathotypes in Children Under Five Years in Aleppo City

Diarrheagenic Escherichia coli (DEC) strains can be classified into six main pathotypes based on their specific virulence properties. These pathotypes are associated with certain serotypes and exhibit distinct epidemiological and clinical features. The identification of DEC cannot be based solely on cultural and biochemical criteria, as they are indistinguishable from the non-pathogenic E. coli. However, the presence of virulence genes and DNA sequences specific to DEC can be used to determine its identity. The aim of this study is to investigate the prevalence of Diarrheagenic Escherichia coli (DEC) pathotypes among infected children under 5 years living in the city of Aleppo Syria. From June 2020 to September 2021, one hundred samples of diarrheal were collected from children under five years suffering from diarrhea admitted at Aleppo University Hospital and from some private laboratories in Aleppo city. Escherichia coli pathotypes were detected by using multiplex polymerase chain reaction and Phylogenetic genes were detected by Triplex PCR. The frequency of diarrheagenic E. coli was (48%), the most frequently isolated pathotypes were atypical enteropathogenic E. coli. (42%), followed by enterotoxigenic E. coli (4%), and enteroinvasive E. coli (2%). Enterohemorrhagic E. coli, enteroaggregative E. coli and Diffusely Adherent E. coli were not detected in any sample (0%). The most prevalent phylogenetic group of E. coli was "Phylogenetic group B2" which represented (62%), followed by "Phylogenetic group D" that comprised 33%, followed by "Phylogenetic group A" strains (3%). Strains of the "Phylogenetic group B1" were rare (2%). This study revealed that DEC strains contribute to cause diarrheal diseases in children, EPEC is the most commonly identified DEC strain. B2 and D groups are the most prevalent phylogenetic groups. In addition, they are virulent because these groups are associated with the presence of several virulence factors.

Subjects' Sociodemographics Influence the Transmission Patterns of Diarrheagenic Escherichia coli Pathotypes among Children under 5 Years in Nakuru County.

Diarrheagenic Escherichiacoli (DEC) infections constitute the leading causes of morbidity and mortality among children in Sub-Saharan Africa. However, little has so far been done to properly reveal the pathogenic endowments of DEC in these populations. We evaluated 4 DEC strains among children under 5 years. A cross-sectional study design was employed among 384 positive cases. There was a significant decline in infections associated with DEC as the children grew older (χ2[12] = 87.366: P = [0.000]. A total of 56 (14.6%) cases were 0-12 months, 168 (43.8%) were 13-24 months, 88 (22.9%) were 25-36 months, 40 (10.4%) were 37-48 months, and 32 (8.3%) were 49-60 months. A total of 248 (64.6%) male subjects exhibited more susceptibility to DEC infections than their female counterparts (n = 136 [35.4%]) (χ2[3] =13.313: P = [0.004]. Subjects from urban areas (n = 248 [64.6%]), significantly bored the brunt of infections than those from rural areas (n = 136 [35.4%]) (χ2[3] = 35.147: P = [0.000]. The prevalence of DEC appeared significantly higher during rainy seasons (n = 269 [70.1%]). Young age, male gender, crowding, and rainy season play a central role in the transmission of DEC pathotypes.

Correlation between Escherichia coli resistant gene isolated from stool samples of children under five years and that from consumed water

Diarrheagenic Escherichia coli (DEC) causes enteric infections and diarrhea, especially in young children. Kenya reports around 2.6 million cases and 7,000 deaths annually due to diarrhea. Antibiotic-resistant DEC strains are a significant public health concern, complicating treatment. The objective of this research was to correlate children's water consumption and antimicrobial-resistant DEC development. The study sampled 1124 children under five with diarrhea in Nakuru, Kenya, using a case-control design. Among 384 eligible children, 192 cases showed Amoxicillin-resistant DEC. Water samples from households were collected and analyzed for DEC presence. The samples were filtered, plated onto MacConkey agar, and subcultured onto Eosin Methylene Blue agar for further analysis. The DEC pathotypes were identified based on morphological and biochemical characteristics, and antibiotic resistance was assessed using the Kirby-Bauer disk diffusion method. The study revealed a strong correlation of 11.613 (95 % Confidence Interval [CI]: 6.495–20.765, p-value: 0.000) between microbial burden in vended water (water sold by vendors) used by different households consumption and antimicrobial resistance in DEC. Water sources showed a high prevalence of DEC, primarily Enteroaggregative, enteropathogenic, enterotoxigenic, and enteroinvasive E. coli. DEC isolates also exhibited varying antibiotic resistance, and genes like blaCTX-M, blaTEM, and blaSHV were identified using PCR. The Spearman correlation coefficient was one, showing that resistance genes in water and stool were perfectly correlated. The study emphasizes the significance of improving water quality, hygiene, and antibiotic-resistant bacteria control to prevent and manage DEC and infectious diseases in Kenya. To combat outbreaks, effective surveillance and rapid reaction procedures are essential. The findings help to shape public health policies and initiatives.

Antibiotic utilization and resistance in diarrheagenic Escherichia coli isolated from children under 5 Years in Nakuru County: a case-control study

Background: Children under the age of 5 years continue to suffer the ravaging effects of microbial resistance. Majority of the infections associated with this age are of bacterial and viral nature. Highest mortalities in this age group are those associated with enteric and diarrheal diseases. Diarrheagenic Escherichia coli (DEC) is among the leading causes of these diseases due to their ubiquitous nature. Methods: The study adopted a case-control design and aimed at investigating antibiotic utilization and resistance in DEC strains isolated from children under 5 years in Nakuru County. A total sample size of 384 children were considered. Stool samples from anal swabs were obtained and cultured on Eosin Methylene Blue (EMB). Antimicrobial susceptibility testing was done using the Kirby-Bauer disk diffusion method to segregate the resistant DEC isolates against amoxicillin, ampicillin, erythromycin, cefoxitin and nalidixic acid. Results: All the DEC (n=192, 100%) strains were resistant to amoxicillin, n=168, 87.5% were resistant to ampicillin, n=156, 81.3% to erythromycin n=72, 37.5% to cefoxitin and only n=64, 33.3% to nalidixic acid. Based on demographic factors, it was that observed self-medication leads among factors contributing to the observed trend in antimicrobial resistance (AMR). Other factors such the length of antibiotic use did not show any level of significance (p<0.05). Conclusions: Thus, we conclude that a conglomerate of several factors is associated with the rising cases of AMR among the DEC strains. Notably, the use of first-line antibiotics especially the β-lactams poses a critical health concern being the most resisted class of antibiotics. Therefore, the current study unravels the need to remediate the effects of AMR among the DEC strains through proper formulation and implementation of guidelines on antibiotic usage.

Drug resistance and molecular typing of diarrheagenic escherichia coli from the diarrhea clinics in Qingpu District, Shanghai City from 2015 to 2019

Objective: To analyze the drug resistance and multilocus sequence typing of five types of diarrheagenic Escherichia coli (DEC) isolated from diarrhea outpatients of diarrhea comprehensive monitoring designated hospital in Qingpu District, Shanghai City from 2015 to 2019. Methods: From January 2015 to December 2019, five types of DEC, isolated and identified from diarrhea outpatient cases' anal swabs of the Qingpu branch of Zhongshan Hospital were collected to determine the minimal inhibitory concentration by using the micro broth dilution susceptibility test. The strains, resistant to the third-generation cephalosporins or carbapenems, or producing ESBLs, were selected based on the results of sensitivity tests and determined by WGS. The MLST typing of DEC was analyzed based on the WGS technology and the minimum spanning tree was constructed by BioNumerics 7.6 software to analyze the local dominant flora. Results: A total of 513 strains of DEC were detected and isolated from 4 494 anal swabs, with a detection rate of 11.42%. About 500 strains were tested for drug sensitivity to nine antibiotics in four classes, including 330 strains of enterotoxigenic E.coli (ETEC), 72 strains of enteroaggregative E.coli (EAEC), 95 strains of enteropathogenic E.coli (EPEC), 1 strain of enterohemorrhagic E.coli (EHEC), and 2 strains of enteroinvasive E.coli (EIEC). From 2015 to 2019, the resistance rate of cefotaxime-clavulanic acid was significantly different (P<0.05). The resistance rate of virulence types of DEC to nalixic acid was significantly different (P<0.05). About 71 strains of DEC were determined by WGS, and 77 drug-resistant genes were detected. Strains were classified into 32 ST subtypes, with the dominant genotypes being ST-1491 (29.6%, 21/71) and ST-10 Complex (23.9%, 17/71). All ST-1491 produced ESBLs, which were blaCTX-M gene mutant strains. The dominant type of ST-10 complex was ST-218 (35.3%, 6/17). In addition, 8 strains of EAEC, 14 strains of EPEC and 49 strains of ETEC were classified into 7, 14 and 18 ST subtypes, respectively. Conclusion: The drug resistance of DEC strains from the diarrhea outpatient case of Qingpu District is serious. The ST types of EAEC and EPEC are highly polymorphic. The dominant ST types of DEC are basically consistent with the common genotypes in southeast China.

Prevalence and Antibiotic Resistance Pattern of Diarrheagenic Escherichia coli Pathotypes Among Children under 5 Years in Khuzestan, Iran

Background: Diarrhea is a life-threatening cause of high mortality, especially among children living in areas with poor sanitation. Enterobacteriaceae is one of the serious causes of bacterial diarrhea in children and adults. In this family, infection with diarrheagenic Escherichia coli (DEC) pathotypes in children is associated with extensive health risks and is of particular importance. In this study, we compared the distribution of pathotypes, epidemiological patterns, and antibiotic resistance of DEC in two diarrheal and non-diarrheal groups among children less than 5 years. Methods: In this study, 303 stool samples were collected from patients admitted to Golestan hospitals in Ahvaz and Dr. Ganjavian in Dezful, Khuzestan. To this end, 201 samples from children with diarrhea (case group) and 102 samples from healthy children (control group) were examined. DEC was characterized by polymerase chain reaction (PCR) for each stool sample, and DEC isolates were tested with antibiotic resistance tests against different antibiotic agents to identify the prevalence of multidrug-resistant (MDR) strains in both groups. Results: DEC was found in 24% (48 out of 200) of the children with diarrhea and 3.8% (4 out of 103) of the healthy children. Enteroaggregative E. coli (EAEC) was the DEC most frequently associated with diarrhea (32 out of 48, 66.6%), which was followed by enteropathogenic E. coli (EPEC) 22.9% (11 out of 48, 22.9%), and enterotoxigenic E. coli (ETEC) (5 out of 48, 10.4%) from children with diarrhea. Four DEC isolates were identified in healthy children: EAEC (2 out of 4, 50%) and EPEC (2 out of 4, 50%) in the healthy group, but no enteroinvasive E. coli (EIEC) or enterohemorrhagic E. coli (EHEC) strains were found in both groups in this study group. In general, DEC isolates exhibited high resistance to ceftriaxone and cefotaxime, and 33 (63.4%) isolates of DEC were MDR. Conclusion: A high prevalence of DEC strains was observed in the group of children with diarrhea and healthy children. Accordingly, further attention should be paid to continuous monitoring of the prevalence and pattern of antibiotic resistance of diarrheal bacterial isolates among children and the whole community.

Detection and antibiotic resistance of diarrheagenic Escherichia coli from patients with diarrhea in Ulaanbaatar, Mongolia.

Diarrheal diseases are common with worldwide distribution, and diarrheagenic Escherichia coli (DEC) strains are the main causative agents. The present study aimed to define the association of various pathotypes of E. coli from diarrheal patients in Mongolia. A total of 341 E. coli strains were isolated from the stool of diarrheal patients. Bacterial susceptibility to antimicrobial agents was determined by the Kirby Bauer disk diffusion method. DEC isolates were identified by HEp-2 cell adherence assay and multiplex polymerase chain reaction (PCR). DEC pathogens were detected in 53.7% of 341 E. coli isolates. Enteroaggregative E. coli (EAEC) was the most common DEC pathotype identified by HEp-2 adherence assay and multiplex PCR methods in 97 samples (28.4%), followed by atypical enteropathogenic E. coli (EPEC) in 50 samples (14.7%), diffusely adherent E. coli (DAEC) in 25 samples (7.3%), enterohaemorrhagic E. coli (EHEC) in 6 samples (1.8%), enterotoxigenic E. coli (ETEC) in 4 samples (1.2%), and enteroinvasive E. coli (EIEC) in 1 sample (0.3%). DEC strains had > 50% antibiotic resistance against cephalothin, ampicillin, and trimethoprim/sulfamethoxazole. All tested DEC strains were susceptible to imipenem. Among the 183 DEC strains, 27 (14.8%) were extended spectrum beta-lactamase producing isolates, and 125 (68.3%) isolates were multiple drug resistant. We have identified six pathotypes of DEC from the clinical isolates tested and concluded that a high prevalence of antimicrobial resistance was observed in these pathotypes. EAEC was the most common pathotype identified and this is the first report of EHEC identification in Mongolia.

Prevalence of Multidrug-Resistant Diarrheagenic Escherichia coli in Asia: A Systematic Review and Meta-Analysis.

Diarrhea is one of the leading causes of morbidity and mortality in developing countries. Diarrheagenic Escherichia coli (DEC) is an important bacterial agent for diarrhea in infants, children, and international travelers, and accounts for more than 30% of diarrheal cases in children less than 5 years old. However, the choices of antimicrobial agents are now being limited by the ineffectiveness of many first-line drugs, in relation to the emergence of antimicrobial-resistant E. coli strains. The aim of this systematic review and meta-analysis was to provide an updated prevalence of antimicrobial-resistant DEC in Asia. A comprehensive systematic search was conducted on three electronic databases (PubMed, ScienceDirect, and Scopus), where 40 eligible studies published between 2010 and 2022 were identified. Using meta-analysis of proportions and a random-effects model, the pooled prevalence of DEC in Asian diarrheal patients was 22.8% (95% CI: 16.5–29.2). The overall prevalence of multidrug-resistant (MDR) and extended-spectrum beta-lactamase (ESBL)-producing DEC strains was estimated to be 66.3% (95% CI: 58.9–73.7) and 48.6% (95% CI: 35.1–62.1), respectively. Considering antimicrobial drugs for DEC, the resistance prevalence was highest for the penicillin class of antibiotics, where 80.9% of the DEC isolates were resistant to amoxicillin and 73.5% were resistant to ampicillin. In contrast, resistance to carbapenems such as imipenem (0.1%), ertapenem (2.6%), and meropenem (7.9%) was the lowest. The relatively high prevalence estimation signifies that the multidrug-resistant DEC is a public health threat. Effective antibiotic treatment strategies, which may lead to better outcomes for the control of E. coli infections in Asia, are necessary.

Genotyping Based on CRISPR Loci Diversity and Pathogenic Potential of Diarrheagenic Escherichia coli.

Diarrheagenic Escherichia coli (DEC) can cause epidemic diarrhea worldwide. The pathogenic potential of different strains is diverse and the continuous emergence of pathogenic strains has brought serious harm to public health. Accurately distinguishing and identifying DEC with different virulence is necessary for epidemiological surveillance and investigation. Clustered regularly interspaced short palindromic repeats (CRISPR) typing is a new molecular method that can distinguish pathogenic bacteria excellently and has shown great promise in DEC typing. The purpose of this study was to investigate the discrimination of CRISPR typing method for DEC and explore the pathogenicity potential of DEC based on CRISPR types (CT). The whole genome sequences of 789 DEC strains downloaded from the database were applied CRISPR typing and serotyping. The D value (Simpson’s index) with 0.9709 determined that CRISPR typing had a higher discrimination. Moreover, the same H antigen strains with different O seemed to share more identical spacers. Further analyzing the strains CRISPR types and the number of virulence genes, it was found that there was a significant correlation between the CRISPR types and the number of virulence genes (p < 0.01). The strains with the largest number of virulence genes concentrated in CT25 and CT56 and the number of virulence genes in CT264 was the least, indicating that the pathway potential of different CRISPR types was variable. Combined with the Caco-2 cell assay of the laboratory strains, the invasion capacity of STEC strains of different CRISPR types was different and there was no significant difference in the invasion rate between different CRISPR type strains (p > 0.05). In the future, with the increase of the number of strains that can be studied experimentally, the relationship between CRISPR types and adhesion and invasion capacities will be further clarified.

Presence of Resistant DEC Strains in a Tertiary Healthcare Center in North East India in Children under 18 Years.

Introduction Diarrheal illness such as diarrheagenic Escherichia coli (DEC), apart from rotavirus, is a common etiological agent known to cause moderate-to-severe diarrhea in low-income countries where unregulated use of antibiotics is rampant, giving rise to multidrug resistant (MDR) strains. This study is an earnest effort in reflecting the resistance pattern in such isolates. Materials and Methods It is a hospital-based cross-sectional study conducted over a period of 1 year (January to December, 2015). Children aged less than 18 years presenting with ( n = 170) and without ( n = 47) diarrhea were included as cases and controls, respectively. Fresh stool sample from eligible participants was collected and inoculated on MacConkey agar. Based on the colony morphology and biochemical identification followed by polymerase chain reaction (PCR), different pathotypes of DEC were identified. All such isolates were subjected to antimicrobial susceptibility testing employing VITEK 2 identification system. The result of the tested antibiotics was evaluated as per Clinical and Laboratory Standards Institute 2015 guidelines. Results DEC with specific virulence genes were detected by multiplex real-time PCR in 39 and 3 children with or without diarrhea, respectively. Most common DEC pathotypes found were enteroaggregative E. coli (38%) followed by enteropathogenic E. coli (28.5%). MDR isolates comprised 35 of 42 DEC pathotypes (83.3%). Resistance among DEC pathotypes to ampicillin, amoxicillin–clavulanate, ciprofloxacin, cephalosporin, nalidixic acid, imipenem, and cotrimoxazole was found to be statistically significant in comparison to non-DEC isolates. Conclusion This study has highlighted the increased prevalence of MDR strains among DEC pathotypes. Looking for these isolates will help detect dreadful DEC pathotypes like enterohemorrhagic E. coli where early administration of a sensitive antibiotic will go a long way in preventing complication like hemorrhagic colitis and hemolytic uremic syndrome.

Drug resistance characteristics of Diarrheagenic Escherichia coli isolated from patients with diarrhea in Shunyi district of Beijing, 2013–2019

Objective To study the drug resistance characteristics of Diarrheagenic Escherichia coli (DEC) isolated from patients with diarrhea in two sentinel hospitals in Shunyi district of Beijing during 2013—2019. Method Stool samples of diarrhea patients were collected in the two sentinel hospitals during this period. Isolation, bacterial identification and PCR typing were conducted for DEC strains. Antimicrobial susceptibility tests were carried out using micro broth method to analyze the drug resistance characteristics of the isolated strains, including resistance rate, non-sensitive rate, multi-drug resistance rate and drug resistance spectrum. Result The detection rate of DEC in diarrhea patients was 9.53% (232/2434). The proportions of Enterotoxic Escherichia coli (ETEC), Enteropathogenic Escherichia coli (EPEC), and Enteroaggregative Escherichia coli (EAEC) were 56.47% (131/232), 27.16% (63/232) and 16.38% (38/232), respectively. The multi-drug resistance rates of DEC with 90 drug resistance spectrum, ETEC with 36 drug resistance spectrum, EPEC with 42 drug resistance spectrum, and EAEC with 23 drug resistance spectrum were 33.19% (77/232), 17.56% (23/131), 58.73% (37/63), 44.74% (17/38), respectively. Antibacterial drugs with resistance rate ≥30% included nudicacid (NAL) and ampicillin (AMP) for ETEC; AMP, tetracycline (TET), sulfamethoxazole tablets (SXT), sulfamethoxazole (Sul), NAL for EPEC; NAL, AMP, SXT, Sul, TET for EAEC. A comparison of the differences in the antimicrobial susceptibility tests during 2013—2016 and during 2017—2019 found that the resistance of ETEC to AMP, cefazolin (CFZ), TET, cefepime (FEP), aztreonam (AZM), and ampicillin/sulbactam (AMS) increased, while the resistance to Sul decreased; the resistance of EPEC to gentamicin (GEN) decreased; the resistance of EAEC to cefotaxime (CTX), GEN, and doxycycline (DOX) decreased. Conclusion Among the diarrhea cases in Shunyi, the intensity of DEC spread was high, and the spread and the drug resistances of ETEC, EPEC and EAEC had unique characteristics. The drug resistance was serious, to which close attention should be paid.

Non-diarrheagenic and diarrheagenic E. coli carrying supplementary virulence genes (SVG) are associated with diarrhea in children from Mexico

Escherichia coli strains, including diarrheagenic E. coli (DEC), are among the most important causes of childhood diarrhea in developing countries. Since these strains also colonize healthy children, additional factors leading to diarrhea remains to be discovered. We therefore conducted a comprehensive study to investigate if supplementary virulence genes (SVG) carried by DEC strains and non-DEC strains, contribute to diarrhea in Mexican children. E. coli strains were isolated from n = 317 children between 6 and 12 years, n = 114 with diarrhea and n = 203 asymptomatic children from Northwestern Mexico, PCR was used to identify SVG, then virulence score and cytotoxic assay in HT-29 cells were performed to evaluate virulence of E. coli strains. DEC prevalence was 18.6% and its presence was significantly associated with diarrhea cases. aEPEC, tEAEC, ETEC, DAEC, aEAEC, tEPEC, and EIEC pathotypes were identified. aEPEC strains were significantly associated with asymptomatic children, whereas ETEC was only identified in children with diarrhea. E. coli strains carrying colonization-related SVG and/or proteolysis-related SVG were significantly associated with diarrhea. DEC strains were associated to diarrhea if strains carried SVG ehaC, kps, nleB, and/or espC. Virulence score was significantly higher in E. coli from diarrhea cases than asymptomatic. In addition, DEC strains carrying SVG+ were more virulent, followed by non-DEC SVG+ strains, and correlated with the cytotoxicity assay. Nearly 50% of DEC strains were MDR, and ~10% were XDR. In conclusion the findings of this work provide evidence that the presence of E. coli strains (regardless if strains are DEC or non-DEC) with SVG were associated with diarrhea in Mexican children.

Occurrence, pathotypes, and antimicrobial resistance profiles of diarrheagenic Escherichia coli strains in animal source food products from public markets in Mashhad, Iran

Diarrheagenic Escherichia coli (DEC) strains are common pathogens that transmitted through the consumption of contaminated foods, and cause acute intestinal diseases in human. The present study was conducted on 300 samples including raw milk, meat and some of their products from November 2016 to October 2017. Microbiological and molecular diagnostic techniques were used to identification of DEC. A total of 69% (207/300) E. coli was isolated and the frequency of DEC was 25.6% (53/207). The pathogenic groups of DEC recovered from the isolates had the following profile: Shiga-like toxin producing E. coli (STEC): 62.3%, enteropathogenic E. coli (EPEC): 24.5%, enteroaggregative E. coli (EAEC): 9.4%, and enterotoxigenic E. coli (ETEC): 3.8%. Neither enteroinvasive E. coli (EIEC) nor diffusely adherent E. coli (DAEC) were found. The highest incidence values were found in hamburgers (46.7%), and the highest rate of DEC positive prevalence was in March. Of the DEC strains, 90.6% (48/53) displayed resistance to at least one antibiotic and the highest level of resistance was found for tetracycline (69%). The obtained results revealed that the studied animal source food products may easily act as a reservoir of DEC with a potential ability to transfer antibiotic resistance and virulence genes to the gastrointestinal microbiota. Therefore, it is of paramount importance to develop effective strategies for improving food safety and updated guidelines for the prudent use of antimicrobial agents in Iran.

Virulence Profiles of Diarrheagenic &lt;i&gt;Escherichia coli&lt;/i&gt; Isolated from the Western Region of Ghana

Diarrheagenic Escherichia coli (DEC), an important agent of infectious diarrhea, is constantly evolving, making its periodic monitoring necessary. However, the DEC genotypes in Ghana remain uncharacterized. We focused on characterizing the molecular serotypes, virulence factors, multilocus sequence types, and the phylogenetic relatedness among different DEC pathotypes recovered from stool samples of pediatric patients with symptoms of diarrhea from the Western region of Ghana. We detected all five common DEC pathotypes, with the majority of the isolates being enterotoxigenic E. coli (ETEC) harboring the heat-labile enterotoxin gene. The DEC strains exhibited diverse serotypic identity with novel and previously reported outbreak strains. Sequence types (ST) ST38, ST316, and ST1722 were most prevalent, and clonal complex 10 (CC10) was the most common CC. A close evolutionary distance was observed among most of the isolates. Coli surface antigen 6 was the most prevalent (44%, n = 11) ETEC-specific colonization factor. Nearly all the isolates harbored lpfA, and the frequencies of other virulence genes such as pap and cnf1 were 7.9% and 18.4%, respectively. This study provides insights into the important and novel genotypes circulating in the Western region of Ghana that should be monitored for public health.

Antibiotic resistance and virulence patterns of pathogenic Escherichia coli strains associated with acute gastroenteritis among children in Qatar

BackgroundThe treatment of Enterobacteriaceae family including diarrheagenic E. coli (DEC) has been increasingly complicated due to the emergence of resistant strains. Here we report on the phenotypic resistance profiles and ESBL genotype and virulence profiles of Enteroaggregative E. coli (EAEC) and Enteropathogenic E. coli (EPEC) isolated from children hospitalized with acute gastroenteritis in Qatar (AGE).ResultsE. coli were isolated and characterized from 76 diarrheagenic stool positive samples, collected from hospitalized children less than 10 years old. Isolates were tested for antibiotic susceptibility against eighteen clinically relevant antibiotics using E-test method. Conventional PCR was performed to detect genes encoding ESBL and virulence factors. Chi-square test was performed to compare the individual antibiotic resistance between EPEC and EAEC.A significant percentage (73.7%) of isolates were resistant to at least one antibiotic. Overall, high resistance (70%) was reported to the first-line antibiotics such as ampicillin, tetracycline (46.4%), and sulfamethoxazole-trimethoprim (42.9%). Further, 39.5% of the isolates were multidrug resistant (MDR), with 22.4% being ESBL producers. On the other hand, all isolates were susceptible to carbapenem, fosfomycin, amikacin and colistin. The incidences of resistance to the 18 antibiotics between EPEC and EAEC were not significantly different by Pearson chi -square test (P > 0.05). Genetic analysis revealed that 88.23% of ESBL production was blaCTX-M-G1 (blaCTX-M-15, blaCTX-M-3) - encoded. Several different combinations of virulence markers were observed, however, there was no specific trend among the isolates apart from absence of the bundle-forming pilus (bfpA) gene, which encodes the type IV fimbriae in EPEC adherence factor (EAF) plasmid (pEAF), among all EPEC (atypical). 15% of the EAEC strains were positive for a combination of astA, aap & capU, while 10% were positive for three different combinations. The aap, aatA, capU and aggR virulence genes showed the highest frequency of 65, 60, 55 and 55% respectively. Others genes, east, astA, and aai, showed frequencies of 35, 30 and 20% respectively.ConclusionsAtypical EPEC and EAEC were the primary etiological agents of diarrhea in children among DEC pathotypes. Our results indicated high rate of antimicrobial resistance pattern of DEC strains, which necessities the development of regulatory programs and reporting systems of antimicrobial resistance in DEC and other AGE-associated bacteria to insure effective control of diarrheal diseases. Results from this study demand a further research on identifying the phenotypic and genotypic profiles of more DEC pathotypes in various clinical samples.

Captive Green Iguana Carries Diarrheagenic Escherichia coli Pathotypes.

The green iguana appears to be a carrier for bacteria causing gastrointestinal infections in humans. The presence of diarrheagenic E. coli (DEC) pathotypes, however, has not been studied in this reptile. The aim of the current work was to investigate the prevalence of DEC in the intestines of 240 captive green iguanas, their phylogenetic groups, and the antibiotic susceptibility profile. E. coli strains were isolated from 41.7% (N = 100/240) of the intestinal content of green iguanas. DEC strains was identified in 25.9% of the screened population and were detected in the majority (62%, p = 0.009) of those reptiles carrying E. coli strains. Among DEC strains, STEC strains carrying the stx1 gene were the most prevalent pathotype isolated (38.7%), followed by EAEC and ETEC (27.4% each). Genetic markers of DEC strains belonging to the EHEC pathotype were not detected. More than a half of DEC strains were classified into the Clade I-II phylogroup (64.5%), followed by the phylogroup A (14.5%). The antibiotic susceptibility method demonstrated that a high proportion of DEC strains were resistance, or non-susceptible, to carbenicillin, amikacin, and ampicillin. We conclude that the green iguana kept in captivity is a carrier of DEC strains bearing resistance to first-line antibiotics, including penicillins. Given the increase presence of the green iguana in Latin American households, these reptiles represent a potential source of transmission to susceptible humans and therefore a potential source of gastrointestinal disease.