Role of Enteropathogenic Escherichia Coli in Paediatric Diarrhoeas in South India

Abstract

Background:Enteropathogenic Escherichia coli(EPEC) is a major cause of diarrhoea in children below 5 years of age. Serotyping is classical method for identification of EPEC strains. But serotypic markers are rarely sufficient to reliably identify the strains as Escherichia coli. Introduction of PCR methodology which depends on detection of virulence factors has provided a practical and rapid way of detecting diarrhoeagenic Esch.coli. Multiantibiotic resistant EPEC strains are a common phenomenon with world wide extension. Moreover for the selection of appropriate therapy of dirrhoeas, knowledge of local antimicrobial therapy pattern plays an important role.Objectives:To study the role of EPEC in Paediatric diarrhoea by both Serogrouping and Molecular characterisation by PCR and to analyse the antibiotic susceptabililty patterns of EPEC strains in our area.Materials and methods:Prospective study of stool samples collected from children with diarrhoea and without diarrhoea who were below 5 years of age was conducted from May to November 2011. Escherichia.coli isolates were identified by Microscopy, Culture and Biochemical reactions. Among the Escherichia coli isolates, EPEC isolates were identified by Serogrouping. Escherichia coli isolates were also subjected to Molecular characterisation by Multiplex PCR assay and those isolates which showed pathogenic genes were futher serotyped. Antibiotic susceptibility pattern of EPEC isolates was determined by CLSI guidelines.Results:Among the Escherichia coli isolates 36.8% in the diarrhoeal group and none of them from the nondiarrhoeal group were identified as EPEC by serogrouping. 73.3% of the EPEC isolates were below 2 years of age and no much difference in the sex distribution was observed. Mild to moderate dehydration and feccal leuckocytes were seen in 59.9% and 56.6% of isolates respectively. High resistance to Nalidixic acid, Ampicillin, Cotrimoxazole, Ciprofloxacin and Norfloxacin was observed in the diarrhoeal group and resistance to only ampicillin was seen in the nondiarrhoeal group. In the diarrhoeal group 38.8% of Escherichia coli were EAEC and no other diarrhoeagenic Escherichia coli group was found by molecular characterisation. In the nondiarrhoeal Escherichia coli strains, 46.6% showed EAEC genes. EAEC strains in the diarrhoeal group belonged to multiple serotypes, the most common serotype being ONT and in the nondiarrhoeal group, 85.7% were of a single serotype, the most common isolate being O153. Among the Escherichia coli isolates which agglutinated with EPEC polyvalent antisera, 33.3% were positive for Enteroaggregative genes. (Table 1).Conclusion:EPEC is still an important pathogen in paediatric diarrhoeas. O serogrouping can still be relied upon for detection of EPEC. Dehydration is one of the clinical features of EPEC diarrhoea. Fluoroquinolones should only be prescribed in children as second line antibiotics. EAEC are present in classical ‘ O ’ serogroups. Serotype O 153 has an increasing potential for asymptomatic carrier state in children below 5...

Distribution of Integrons and Phylogenetic Groups among Enteropathogenic Escherichia coli Isolates from Children <5 Years of Age in Delhi, India

“…EPEC strains are non-invasive and cause watery diarrhea after formation of attaching and effacing (A/E) lesions (Nataro and Kaper, 1998; Ochoa and Contreras, 2011). As indicated in Table 1, EPEC were found to be significantly present in diarrheagenic cases (80%) and healthy controls (57.5%) which is in accordance with other Indian studies [36.58% and 0% (Tilak and Mudaliar, 2012); 16 and 3% (Hegde et al, 2012)] and worldwide studies viz. 56.7 and 8.3% in Iran, 18.3 and 5.6% in Brazil, 3.95 and 0% in Hong Kong, 13.7 and 5.5% in Tunisia and 6.17 and 1.96% in Rondonia, Western Amazon region, Brazil in diarrheagenic cases and healthy controls respectively (Tsukamoto et al, 1992; Biswas et al, 1996; Alikhani et al, 2006; Orlandi et al, 2006; Ben Salem-Ben Nejma et al, 2014).…”

Comparative analysis of virulence determinants, antibiotic susceptibility patterns and serogrouping of atypical enteropathogenic Escherichia coli versus typical enteropathogenic E. coli in India

“…Scant data are available from India on antibiotic resistance profiles. In a study by Tilak & Mudaliar (2012), 30 EPEC isolates showed 100 % susceptibility to amikacin, 46.6 % to norfloxacin and 36.7 % to ciprofloxacin. Resistance was observed to cotrimoxazole (34.4 %), nalidixic acid (30 %) and ampicillin (30 %).…”

Molecular characterization of diarrheagenic Escherichia coli pathotypes: Association of virulent genes, serogroups, and antibiotic resistance among moderate‐to‐severe diarrhea patients

“…Characterization of E. coli somatic “O” antigen still appears to be useful technique for conventional identification of certain DEC pathotypes . The serogroup O26 was most commonly observed followed by O2, O41, O35, O126, and O1.…”

“…Interestingly, few isolates belong to untypeable or rough classes in various categories of DEC pathotypes. From the literature, E. coli serogroups are much related to identification of clonal variant of DEC pathotypes rather than precise identification …”

“…39 Characterization of E. coli somatic "O" antigen still appears to be useful technique for conventional identification of certain DEC pathotypes. 14,[74][75][76] The serogroup O26 was most commonly observed followed by O2, O41, O35, O126, and O1. Similar to our study, serogroups O26, O2 were found to be associated severe diarrhea cases.…”