Genotypic and phenotypic analysis of diarrheagenic Escherichia coli strains isolated from Brazilian children living in low socioeconomic level communities
نویسندگان
چکیده
BACKGROUND Childhood diarrheal diseases remain highly endemic in developing areas of Brazil. The importance of Escherichia coli among children with diarrhea in these areas was unknown. This study determined the prevalence of different E. coli categories in symptomatic and asymptomatic children from low socioeconomic level rural communities in southeastern Brazil. METHODS A total of 560 stool samples were collected from 141 children with diarrhea (< 10 years) and 419 apparently healthy controls who resided in 23 communities. E. coli isolates (n = 1943) were subjected to two multiplex PCRs developed for the detection of enteropathogenic E. coli (EPEC), enteroaggregative E. coli (EAEC), diffusely adherent E. coli (DAEC), enterotoxigenic E. coli (ETEC), enteroinvasive E. coli (EIEC), and Shiga toxin-producing E. coli (STEC). Strains were also examined for the presence of EPEC, EAEC, and DAEC by assays of adhesion to HEp-2 cells and by hybridization with specific DNA probes. RESULTS Diarrheagenic E. coli strains were isolated from 253 (45.2%) children, and were associated with diarrhea in children aged < 5 years (p < 0.001). EAEC (20.9%), DAEC (11.6%), EPEC (9.3%) were the most frequent pathotypes, followed by ETEC (2.7%), EIEC (0.5%), and STEC (0.2%). Depending of the assay, EPEC, EAEC, and DAEC (collectively termed enteroadherent E. coli) strains were isolated in 45% to 56% of diarrhea cases, a significantly higher incidence than in controls (P < 0.05). Individually, only DAEC showed significant association with diarrhea (p < 0.05), particularly in children aged 2-5 years. CONCLUSION This study indicates that enteroadherent E. coli is an important cause of diarrhea in children living in low socioeconomic level communities in southeastern Brazil. Our results reveal that the PCR1 assay is an excellent tool for the identification of EAEC and DAEC.
منابع مشابه
Frequency and Antibiotic Resistance Pattern of Diarrheagenic Escherichia coli (DEC) Strains Isolated from Children Aged Less Than 10 Years
ABSTRACT Background and Objectives: Diarrheagenic Escherichia coli (DEC) pathotypes are important causes of diarrhea among children in developing countries. The objective of this study was to determine the frequency and antibiotic resistance pattern of DEC pathotypes in children aged less than 10 years. &nbs...
متن کاملGenotypic and phenotypic characterization of enteroaggregative Escherichia coli (EAEC) isolates from diarrheic children: An unresolved diagnostic paradigm exists
Objective(s): The enteroaggregative Escherichia coli (EAEC) has been one of the most intriguing emerging bacterial pathogens in children that occur both in developing countries and the industrial world. Although various phenotypic and genotypic based protocols have been suggested for diagnosis of EAEC, they are not conclusive or practical to be used in most clinical la...
متن کاملAdherence patterns of diarrheagenic Escherichia coli strains isolated from children with gastrointestinal diarrhea and matched controls in a Hep-2 cell adhesion assay
In the present study, carbon species including organic carbon (OC), elemental carbon (EC), and water-soluble organic carbon (WSOC) concentration in PM2.5 were assessed at an urban site of Tehran, Iran during March to June 2014. The PM2.5 samples were collected using an frmOMNITM Ambient Air Sampler. Thermal gravimetric analysis (TGA) was used to analyze OC and EC. The results showed that PM2.5 ...
متن کاملEnteroaggregative Escherichia Coli (EAEC) in South of Iran
Introduction: The aim of the present study was to investigate the presence and the frequency of EAEC as etiologic agent of diarrhea in Shiraz. Enteroaggregative E. coli (EAEC) is increasingly recognized as a cause of often persistent diarrhoea in children and adults in both developing and developed countries, and have been identified as the cause of several outbreaks worldwide. Materials and...
متن کاملMolecular Epidemiology of ESBL Genes and Multi-Drug Resistance in Diarrheagenic Escherichia coli strains Isolated from Adults in Iran
Resistance to oxyimino cephalosporins antibiotics in Enterobacteriaceae is primarily done by the extended spectrum β-lactamases (ESBLs). Clear identification of risk factors for ESBL-producing infections is necessary. Therefore, efficient strategies can be developed to decrease outbreak of these infections. The aim of this study was to determine the antibacterial susceptibility and ESBLs patter...
متن کامل