Diarrheagenic Escherichia Coli Pathotypes Research Articles

Detection and antibiogram profile of diarrheagenic Escherichia coli isolated from two abattoir settings in northwest Ethiopia: a one health perspective

BackgroundDiarrheagenic Escherichia coli (E. coli) is a zoonotic pathogen that contaminates abattoir workers, slaughter environments, slaughter equipment, and carcasses during abattoir processing. Infection with E. coli is associated with the consumption of contaminated food and water, and it is a potential threat to the health and welfare of both humans and animals. Hence, this study aimed to detect diarrheagenic E. coli and assess its antibiogram profile in two abattoir settings, in one health lens.MethodsA cross-sectional study in one health approach was conducted from December 2020 to June 2021. A total of 384 samples from abattoir workers’ hands, carcasses, knives, cattle feces, abattoir water and effluents were collected. Bacterial culture and biochemical tests were conducted to isolate E. coli, while conventional polymerase chain reaction was performed to identify virulence genes. The antibiogram of diarrheagenic E. coli was tested against nine antimicrobials using the Kirby Bauer disk diffusion method.ResultsA total of 115 (29.95%) E. coli were isolated from the 384 samples, and from these isolates, about 17 (14.8%) were confirmed to be diarrheagenic E. coli (DEC). Among the DEC pathotypes, nine (52.94%), five (29.4%), and three (17.65%) were Shiga toxin-producing, enterohemorrhagic, and enterotoxigenic E. coli, respectively. While 14 (82.35%) DEC isolates harbored the stx2 gene, five (29.41%) the eae gene, five (29.41%) the hlyA gene and three (17.65%) harbored the st gene. All the DEC isolates were resistant to erythromycin and vancomycin; whereas, they were susceptible to ampicillin, nalidixic acid and norfloxacin. Furthermore, 64.7% of DEC isolates showed resistance to both ceftazidime and kanamycin and 88.24% of the isolates showed multidrug resistance.ConclusionThis study detected DEC isolates having different virulence genes, which showed single and multiple antimicrobial resistance. Given the existing poor hygienic and sanitary practices along the abattoir-to-table food chain, coupled with the habit of raw meat consumption, this result indicates a potential public and animal health risk from the pathogen and antimicrobial resistance.

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.

Characteristics of Pathogenic Escherichia coli Associated with Diarrhea in Children under Five Years in Northwestern Ethiopia.

Diarrheagenic Escherichia coli (DEC) are the leading cause of infectious diarrhea and pose a significant global, regional, and national burden of disease. This study aimed to investigate the prevalence of six DEC pathotypes in children with diarrhea and determine their antibiotic resistance patterns. Samples from 107 diarrheagenic children were collected and processed for Escherichia coli (E. coli). Single-plex PCR was used to detect target virulence genes as well as characterize and categorize DEC pathotypes. Antibiotic resistance patterns were determined by the Kirby-Bauer disk diffusion method. E. coli was detected in 79 diarrheal stool samples, accounting for 73.8% of the samples collected. Additionally, 49.4% (39 out of 79) of the isolates harbored various typical virulence factors. Results revealed six pathotypes of virulence: enterotoxigenic E. coli (ETEC) (53.8%), enteropathogenic E. coli (EPEC) (12.8%), enteroaggregative E. coli (EAEC) (10.3%), Heteropathotypes (7.8%), Shiga toxin-producing E. coli (STEC), and enterohemorrhagic E. coli (EHEC) (7.7% each). The isolates exhibited high antibiotic resistance against trimethoprim/sulfamethoxazole (82.1%), amoxicillin (79.5%), ampicillin (74.4%), gentamicin (69.2%), and streptomycin (64.1%). An overall occurrence of 84.6% of multiple-drug resistance was observed in the isolates, with resistance ranging from three to four antibiotic classes. Our findings revealed a high level of pathogenic E. coli that were highly resistant to multiple categories of antibiotics among children in the Awi zone. These findings highlight the potential role of pathogenic E. coli in childhood diarrhea in tropical low-resource settings and underscore the need for continued research on the characteristics of pathogenic and antibiotic-resistant strains.

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.

Risk factors for diarrheagenic Escherichia coli infection in children aged 6-24 months in peri-urban community, Nairobi, Kenya.

Escherichia coli commonly inhabits the gut of humans and animals as part of their microbiota. Though mostly innocuous, some strains have virulence markers that make them pathogenic. This paper presents results of a cross-sectional epidemiological study examining prevalence of diarrheagenic E. coli (DEC) pathotypes in stool samples of asymptomatic healthy children (n = 540) in Dagoretti South subcounty, Nairobi, Kenya. E. coli was cultured and pathotyped using PCR to target specific virulence markers associated with Shiga-toxin, enteropathogenic, enterotoxigenic, enteroaggregative, entero-invasive and diffusely adherent E. coli. Overall prevalence of DEC pathotypes was 20.9% (113/540) with enteropathogenic E. coli being the most prevalent (34.1%), followed by enteroaggregative E. coli (23.5%) and Shiga-toxin producing E. coli (22.0%) among positive samples. We found evidence of co-infection with multiple pathotypes in 15% of the positive samples. Our models indicated that at the household level, carriage of DEC pathotypes in children was associated with age group [12-18 months] (OR 1.78; 95%CI 1.03-3.07; p = 0.04), eating matoke (mashed bananas) (OR 2.32; 95%CI 1.44-3.73; p = 0.001) and pulses/legumes (OR 1.74; 95%CI 1.01-2.99; p = 0.046) while livestock ownership or contact showed no significant association with DEC carriage (p>0.05). Our findings revealed significant prevalence of pathogenic DEC circulating among presumptive healthy children in the community. Since there has been no previous evidence of an association between any food type and DEC carriage, unhygienic handling, and preparation of matoke and pulses/legumes could be the reason for significant association with DEC carriage. Children 12-18 months old are more prone to DEC infections due to exploration and hand-to-mouth behavior. A detailed understanding is required on what proportion of positive cases developed severe symptomatology as well as fatal outcomes. The co-infection of pathotypes in the rapidly urbanizing environment needs to be investigated for hybrid or hetero-pathotype circulation that have been implicated in previous infection outbreaks.

Molecular Characterization of Hetero-Pathogenic and Diarrheagenic Escherichia coli Pathotypes in Diarrheic Children under Five Years and Exposure Environment in Ogun State, South-West Nigeria.

Diarrheagenic Escherichia coli (DEC) is one of the most common etiological agents of moderate-to-severe diarrhea in Low- and Middle-Income Countries (LMICs). Therefore, determining the source(s) of DEC in index cases and exposure environment is important for developing a prevention strategy. The current study aims to investigate the prevalence of DEC among children under 5 years and their exposure environment in Ogun State, Nigeria. Samples from 228 diarrheic children and their exposure environment were collected and screened for E. coli. Bio-chemically compatible distinct colonies were molecularly characterized using a 7-virulence-gene multiplex PCR with virulence factors (VFs) indicative of four pathotypes of E. coli: enterotoxigenic (ETEC), verotoxigenic (VTEC), enteropathogenic (EPEC), and enteroinvasive (EIEC). Representative pathotypes were subjected to antimicrobial susceptibility and over-expressed efflux pump assays. One or more VFs typical of specific pathotypes were detected in 25.9% (59/228) diarrhea cases consisting of ETEC (21.5%) and EPEC (0.4%), while hetero-pathogenic pathotypes were found in 4.0% of cases. Of the food sources, 27.9% (101/362) were positive for DEC, of which ETEC accounted for 21.0%, VTEC 1.9%, EPEC 0.6%, EIEC 0.6%, and hetero-pathogenic pathotypes were 3.9%. Furthermore, ETEC was the only pathotype detected in the wastewater (4/183). Interestingly, the consumption of street-vended foods was the most significant (p = 0.04) risk factor for DEC infection in the study area. A total of 73.3% of selected DEC pathotypes showed resistance to antimicrobials, while 27.5% demonstrated over-expression of efflux pump activity. The high prevalence of ETEC across all sources and the occurrence of hetero-pathogenic DEC in diarrheic children and food sources emphasizes the importance of establishing a better strategy for the control and prevention of diarrhea among children in low- and medium-income households.

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

Background: Diarrheagenic Escherichia coli (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. Aims and Objectives: We evaluated 4 DEC strains among children under 5 years. Materials and Methods: A cross-sectional study design was employed among 384 positive cases. Results: 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%]). Conclusion: Young age, male gender, crowding, and rainy season play a central role in the transmission of DEC pathotypes.

Epidemiology and Risk Factors for Diarrheagenic Escherichia coli Carriage among Children in Northern Ibadan, Nigeria.

Diarrhea is a leading cause of childhood morbidity in Africa, but few studies, focus on bacterial diarrheal etiology including multicountry studies that typically excluded Nigeria. We collected stool specimens from 477 children under 5 years of age, 120 with diarrhea, who were enrolled in our prospective case-control study between November 2015 and August 2019. All were attending primary health clinics on the northern outskirts of Ibadan. Up to 10 Escherichia coli isolates were obtained per specimen, and at least three of them were sequenced using Illumina whole-genome sequence technology. Genomes were assembled using SPAdes and evaluated for quality using QUAST. VirulenceFinder was used to identify virulence genes. The microbiological quality of water from 14 wells within the study area was assessed using total and coliform counts. Diarrheagenic E. coli (DEC) were isolated from 79 (65.8%) cases and 217 (60.8%) control children. A number of hybrid DEC pathotypes, Salmonella spp., Yersinia spp., and all DEC pathotypes except Shiga toxin-producing E. coli were detected, but no pathogen showed association with disease (P > 0.05). Enterotoxigenic E. coli were more commonly recovered from children without diarrhea aged below 6 months but exclusively detected in children with diarrhea aged over 9 months. Temporally linked, genetically similar enteroaggregative E. coli were isolated from children in different households in eight instances. No well water sample drawn in the study was potable. Children in northern Ibadan were commonly colonized with DEC. Access to water, proper sanitation, and vaccination against the prevailing pathogens may be critical for protecting children from the less overt consequences of enteric pathogen carriage.

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.

Spatial diarrheal disease risks and antibiogram diversity of diarrheagenic Escherichia coli in selected access points of the Buffalo River, South Africa.

Freshwater sources, often used for domestic and agricultural purposes in low- and middle-income countries are repositories of clinically significant bacterial pathogens. These pathogens are usually diversified in their antibiogram profiles posing public health threats. This study evaluated the spatial diarrhoeal disease risk and antibiogram diversity of diarrheagenic Escherichia coli (DEC) in four access points of the Buffalo River, Eastern Cape Province, South Africa using standard epidemiological, culture, and molecular methods. The diarrhoeal disease risk was characterised using the Monte Carlo simulation, while the antibiogram diversity was assessed using the species observed Whittaker's single alpha-diversity modelling. E. coli mean count was highest in King William's Town dam [16.0 × 102 CFU/100ml (SD: 100.0, 95% CI: 13.5 × 102 to 18.5 × 102)]. Enterohemorrhagic E. coli (stx1/stx2) was the most prevalent DEC pathotype across the study sites. A high diarrhoeal disease risk of 25.0 ×10-2 exceeding the World Health Organization's standard was recorded across the study sites. The average single and multiple antimicrobial resistance indices of the DEC to test antimicrobials were highest in the Eluxolzweni dam [0.52 (SD: 0.25, 95% CI: 0.37 to 0.67)] and King William's Town dam [0.42 (SD: 0.25, 95% CI: 0.27 to 0.57)] respectively. The prevalent antibiotic resistance genes detected were tetA, blaFOX and blaMOX plasmid-mediated AmpC, blaTEM and blaSHV extended-spectrum β-lactamases, which co-occurred across the study sites on network analysis. The phenotypic and genotypic resistance characteristics of the DEC in Maden dam (r = 0.93, p<0.00), Rooikrantz dam (r = 0.91, p<0.00), King William's Town dam (r = 0.83, p = 0.0), and Eluxolzweni dam (r = 0.91, p<0.00) were strongly correlated. At least, three phylogenetic clades of the DEC with initial steep descent alpha-diversity curves for most of the test antimicrobials were observed across the study sites, indicating high diversity. The occurrence of diversified multi drug resistant DEC with diarrhoeal disease risks in the Buffalo River substantiates the role surface water bodies play in the dissemination of drug-resistant bacterial pathogens with public health implications.

Molecular epidemiology and antimicrobial susceptibility of diarrheagenic Escherichia coli isolated from children under age five with and without diarrhea in Central Ethiopia.

Diarrhea is a serious health problem in children, with the highest mortality rate in sub-Saharan Africa. Diarrheagenic Escherichia coli (DEC) is among the major bacterial causes of diarrhea in children under age five. The present study aims to determine molecular epidemiology and antimicrobial resistance profiles of DEC and identify contributing factors for acquisition among children under age five in Central Ethiopia. A health facility-centered cross-sectional study was conducted in Addis Ababa and Debre Berhan, Ethiopia, from December 2020 to August 2021. A total of 476 specimens, 391 from diarrheic and 85 from non-diarrheic children under age five were collected. Bacterial isolation and identification, antimicrobial susceptibility, and pathotype determination using polymerase chain reaction (PCR) were done. Of the 476 specimens analyzed, 89.9% (428/476) were positive for E. coli, of which 183 were positive for one or more genes coding DEC pathotypes. The overall prevalence of the DEC pathotype was 38.2% (183/476). The predominant DEC pathotype was enteroaggregative E. coli (EAEC) (41.5%, 76/183), followed by enterotoxigenic E. coli (21.3%, 39/183), enteropathogenic E. coli (15.3%, 28/183), enteroinvasive E. coli (12.6%, 23/183), hybrid strains (7.1%, 13/183), Shiga toxin-producing E. coli (1.6%, 3/183), and diffusely-adherent E. coli (0.6%, 1/183). DEC was detected in 40.7% (159/391) of diarrheic and 28.2% (24/85) in non-diarrheic children (p = 0.020). The majority of the DEC pathotypes were resistant to ampicillin (95.1%, 174/183) and tetracycline (91.3%, 167/183). A higher rate of resistance to trimethoprim-sulfamethoxazole (58%, 44/76), ciprofloxacin (22%, 17/76), ceftazidime and cefotaxime (20%, 15/76) was seen among EAEC pathotypes. Multidrug resistance (MDR) was detected in 43.2% (79/183) of the pathotypes, whereas extended spectrum ß-lactamase and carbapenemase producers were 16.4% (30/183) and 2.2% (4/183), respectively. All six common DEC pathotypes that have the potential to cause severe diarrheal outbreaks were found in children in the study area; the dominant one being EAEC with a high rate of MDR.

Epidemiology of Enteroaggregative, Enteropathogenic, and Shiga Toxin–ProducingEscherichia coliAmong Children Aged &amp;lt;5 Years in 3 Countries in Africa, 2015–2018: Vaccine Impact on Diarrhea in Africa (VIDA) Study

To address knowledge gaps regarding diarrheagenic Escherichia coli (DEC) in Africa, we assessed the clinical and epidemiological features of enteroaggregative E. coli (EAEC), enteropathogenic E. coli (EPEC), and Shiga toxin-producing E. coli (STEC) positive children with moderate-to-severe diarrhea (MSD) in Mali, The Gambia, and Kenya. Between May 2015 and July 2018, children aged 0-59 months with medically attended MSD and matched controls without diarrhea were enrolled. Stools were tested conventionally using culture and multiplex polymerase chain reaction (PCR), and by quantitative PCR (qPCR). We assessed DEC detection by site, age, clinical characteristics, and enteric coinfection. Among 4840 children with MSD and 6213 matched controls enrolled, 4836 cases and 1 control per case were tested using qPCR. Of the DEC detected with TAC, 61.1% were EAEC, 25.3% atypical EPEC (aEPEC), 22.4% typical EPEC (tEPEC), and 7.2% STEC. Detection was higher in controls than in MSD cases for EAEC (63.9% vs 58.3%, P < .01), aEPEC (27.3% vs 23.3%, P < .01), and STEC (9.3% vs 5.1%, P < .01). EAEC and tEPEC were more frequent in children aged <23 months, aEPEC was similar across age strata, and STEC increased with age. No association between nutritional status at follow-up and DEC pathotypes was found. DEC coinfection with Shigella/enteroinvasive E. coli was more common among cases (P < .01). No significant association was detected between EAEC, tEPEC, aEPEC, or STEC and MSD using either conventional assay or TAC. Genomic analysis may provide a better definition of the virulence factors associated with diarrheal disease.

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.

Occurrence of diarrheagenic Escherichia coli pathotypes from raw milk and unpasteurized buttermilk by culture and multiplex polymerase chain reaction in southwest Iran.

In developing countries including Iran, there are limited data on diarrheagenic Escherichia coli (DEC) contamination in milk and unpasteurized buttermilks. This study aimed to determine the occurrence of DEC pathotypes by culture and multiplex polymerase chain reaction (M-PCR) in some dairy products from southwest Iran. In this cross-sectional study (September to October 2021), 197 samples (87 unpasteurized buttermilk and 110 raw cow milk) were collected from dairy stores of Ahvaz, southwest Iran. The presumptive E. coli isolates were primarily identified using biochemical tests and then confirmed by PCR of uidA gene. The occurrence of 5 DEC pathotypes: enterotoxigenic E. coli (ETEC), enterohemorrhagic E. coli (EHEC), enteropathogenic E. coli (EPEC), enteroaggregative E. coli (EAEC), and enteroinvasive E. coli (EIEC) were investigated using M-PCR. Overall, 76 (76/197, 38.6%) presumptive E. coli isolates were identified by biochemical tests. Using uidA gene, only 50 isolates (50/76, 65.8%) were confirmed as E. coli. DEC pathotypes were detected in 27 of 50 (54.0%) E. coli isolates (74.1%, 20/27 from raw cow milk and 25.9%, 7/27 from unpasteurized buttermilk). The frequency of DEC pathotypes was as follows: 1 (3.7%) EAEC, 2 (7.4%) EHEC, 4 (14.8%) EPEC, 6 (22.2%) ETEC, and 14 (51.9%) EIEC. However, 23 (46.0%) E. coli isolates had only the uidA gene and were not considered DEC pathotypes. Possible health risks for Iranian consumers can be attributed to the presence of DEC pathotypes in dairy products. Hence, serious control and prevention efforts are needed to stop the spread of these pathogens.

A one-step multiplex PCR-based assay for simultaneous detection and classification of virulence factors to identify five diarrheagenic E. coli pathotypes

Human diarrhea-causing strains of Escherichia coli are referred to as diarrheagenic E. coli (DEC). DEC can be divided into five main categories based on distinct epidemiological and clinical features, specific virulence determinants, and association with certain serotypes. In the present study, a simple and rapid one-step single reaction multiplex PCR (mPCR) assay was developed for the simultaneous identification and differentiation of five currently established DEC pathotypes causing gastrointestinal diseases. The mPCR incorporated 10 primer pairs to amplify 10 virulence genes specific to the different pathotypes (i.e., stx1 and stx2 for EHEC, elt and sth for ETEC, eaeA and bfpA for EPEC, aggR and astA for EAEC, and ipaH and invE for EIEC) and to generate DNA fragments of sufficiently different sizes to be unequivocally resolved. All strains were detected at concentrations ranging from 104 to 107 CFU/mL. To demonstrate the utility of the mPCR assay, 236 clinically isolated strains of DEC from two hospitals were successfully categorized. One-step mPCR technique reduced the cost and effort involved in the identification of various virulence factors in DEC. Thus, we demonstrated that the newly developed mPCR assay has the potential to be introduced as a diagnostic tool that can be utilized for the detection of DEC as an additional check in clinical laboratories and for confirmation in health and environment institutes, health centers, and reference laboratories.

What Is behind the Correlation Analysis of Diarrheagenic E. coli Pathotypes?

Simple SummaryTo date, despite the efforts made to monitor the wide spread of resistant pathogens, especially multidrug-resistant (MDR) diarrheagenic E. coli, there are limitations in the correlation analysis for these pathogens worldwide. Therefore, it seems important and so timely to assess the E. coli pathotypes and their correlations with hosts, antimicrobial resistance, virulence gene profiles, and serotypes. Our promising results gave a clear indication for the epidemic situation of diarrheagenic E. coli (DEC) in Egypt and suggested that restricted recommendations and a search for novel alternative therapies are urgently needed due to the wide spread of MDR and multi-virulent E. coli strains in addition to their heterogeneous nature. This study can be implemented in the infection control guidance with enhanced protocols to hinder the spread of MDR E. coli pathotypes in Egyptian hospitals.The treatment failure recorded among patients and animals infected with diarrheagenic Escherichia coli (DEC) was increased due to the presence of specific virulence markers among these strains. These markers were used to classify DEC into several pathotypes. We analyzed the correlations between DEC pathotypes and antimicrobial resistances, the existence of virulence genes, serotypes, and hosts. The ETEC pathotype was detected with a high prevalence rate (25%). Moreover, the ETEC and EPEC pathotypes were highly associated with human infections in contrast to the EIEC and EAEC phenotypes, which were commonly recognized among animal isolates. Interestingly, the antimicrobial resistance was affected by E. coli pathotypes. With the exception of EIEC and STEC, imipenem represented the most effective antibiotic against the other pathotypes. There were fixed correlations between the DEC pathotypes and the presence of virulence markers and hosts; meanwhile, their correlation with serotypes was variable. Additionally, the vast majority of our isolates were highly diverse, based on both phenotypic and ERIC molecular typing techniques. Our promising results gave a clear indication for the heterogeneity and weak clonality of DEC pathotypes in Egypt, which can be utilized in the evaluation of the current therapeutic protocols and infection control guidelines.

Molecular characterization of diarrheagenic Escherichia coli isolates from children with diarrhea: A cross-sectional study in four provinces of Mozambique: Diarrheagenic Escherichia coli in Mozambique

Analyze the frequency of diarrheagenic Escherichia coli (DEC) pathotypes and their antimicrobial resistance profiles among children aged <15 years with diarrhea in four Mozambican provinces. A cross-sectional hospital-based surveillance program of diarrhea was implemented in Maputo, Sofala, Zambézia, and Nampula. A single stool sample was collected from each child from May 2014 to May 2017. Culture methods and biochemical characterization were performed to detect E. coli strains. DEC pathotypes were determined by conventional polymerase chain reaction targeting specific virulence genes. Antimicrobial susceptibility was assessed by the Kirby-Bauer method. From 723 specimens analyzed by culture, 262 were positive for E. coli. A total of 208 samples were tested by polymerase chain reaction for DEC identification, of which 101 (48.6%) were positive for a DEC pathotype. The predominant pathotypes were enteroaggregative (66.3%, 67/101), enteropathogenic (15.8%, 16/101), enterotoxigenic (13.9%, 14/101), and enteroinvasive E. coli (4.0%, 4/101). No Shiga toxin-producing E. coli was identified. Regardless of the province, the most frequent pathotype was enteroaggregative E. coli. Isolated DEC presented high frequency of resistance to ampicillin (97.8%), tetracycline (68.3%), chloramphenicol (28.4%), nalidixic acid (19.5%), and gentamicin (14.4%). Children with diarrhea in Mozambique had DEC and higher resistance to ampicillin and tetracycline.

Study on Molecular Characterization of Diarrheagenic Escherichia coli among Pediatric Patient

Background: Diarrheal diseases are major cause of morbidity and mortality in low‐ to middle‐income countries and estimated to be second leading cause of mortality among children &lt; 5 years of age, resulting in 0.5 million deaths globally. Sub‐Saharan and South East Asian regions account for highest burden of the disease (&gt;72%). Escherichia coli is enormously versatile bacterium which elaborates its commensal and pathogenic potential in human host. Diarrheagenic E. coli (DEC) is reported as one of the leading causes of gastrointestinal disorders worldwide and signified as an important issue to address in public health. Material and Methods: This is a prospective and Cross-sectional study was undertaken among all children diagnosed with diarrhea from both admitted as well as outpatient Index Medical College, Indore. Over a period of 2 years, stool specimen of all patients reporting to the hospital with diarrhea was collected. The present study includes all subjects (children under the age of 5 years) suffering from diarrhea who report to the hospital, both admitted as well as outpatient. Stool samples from each patient, including watery stool (within 24 hours), mucous, purulent blood stool, where the patients had not taken antibiotics was considered. Results: The most of the children were belongs to 4-5 years (50.8%) followed by 3-4 years (32.5%), 2-3 years (14.1 years) and 1-2 years (2.5%). Distribution of male according to different Diarrheagenic strains of EAEC 3, ETEC 13, EPEC 9 and female EAEC 6, ETEC 7, EHEC 1, EPEC 4. Distribution of age according to different Diarrheagenic strains of EAEC of 2-3 years were 2, ETEC 9, EPEC 4 and 4-5 years EAEC 2, ETEC 3, EHEC 1, EPEC 3. Conclusion: Although in our study, proportions of DEC as diarrheal pathogen are limited to a moderate level; however, current study revealed high levels of resistance among DEC pathotypes in hospitalized patients. The observed high resistance rates to antibiotics may be a result of extreme disease severity andpersistence of infections among hospitalized patients.

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.