Molecular Detection of Diarrheagenic Escherichia coli from Children with Acute Diarrhea in Tertiary Care Hospitals of Dhaka, Bangladesh.

Abstract

Objective: Multiplex PCR assay was used for diagnosis of diarrheagenic Escherichia coli (DEC) in stool samples of children (under 5 years) with acute diarrhea. Methods: Samples were collected from January 2011 to December 2011, from Dhaka Medical College Hospital and Dhaka Shishu Hospital. Multiplex PCR with five specific primer pairs to detect enteropathogenic E. coli (eae, bfp), enterotoxigenic E. coli (lt, st) and enteroaggregative E. coli (aat) were used. However, enteroinvasive E. coli, enterohemorrhagicE. coli and diffusely adhererentE. coli were not sought. Result: In total, 135 (67.5%) E. coli were isolated from 200 stool samples. The prevalence of DEC was 68 (34%). Among DEC, most frequently isolated pathotype was EPEC 40 (58.82%), followed by ETEC 24 (35.29%) and EAggEC 18 (26.47%). Among the EPEC, 5 (12.5%) were typical EPEC. Among the 68 DEC positive cases, 22 samples contained more than one pathogenic gene in various combinations. Among the combination of DEC, EPEC+ETEC combination was 6 (27.27%) followed by ETEC+EAggEC 4 (18.18%), EPEC+EAggEC and ETEC+EPEC+EAggEC were both in 3 (13.6%). Conclusion:This study shows that DEC is a common cause of childhood diarrhea in Dhaka city of Bangladesh. By using multiplex PCR assay, DEC can be diagnosed in one PCR reaction that makes a conclusive diagnosis of diarrhea. DOI: http://dx.doi.org/10.3126/ajms.v5i2.8576 Asian Journal of Medical Science, Volume-5(2) 2014: 59-66

Prevalence of Virulence Genes of Diarrheagenic <i>Escherichia coli</i> in Fecal Samples Obtained from Cattle, Poultry and Diarrheic Patients in Bangladesh

“…A total of 78 of hospitalized patients with diarrhea had at least one virulence gene of DEC, even if EAST1EC was excluded. This statistic is higher than that mentioned in previous reports regarding Bangladeshi patients with diarrhea (13,14). Our results imply a very high prevalence of DEC among patients; however, this difference may be attributable to the use of a sensitive multiplex real-time PCR protocol, and not because of an increase in the incidences of DEC infection over time.…”

“…Since the diarrheagenic ability of DAEC is still controversial, these findings suggest that DAEC tends to be associated with EIEC or Shigella infection. In this study, among children with diarrhea, eae was the second most prevalent gene (37 ); this is higher than the statistic mentioned in previous reports regarding subjects with diarrhea in Bangladesh (13,14) and Japan (12). This gene was also highly prevalent in fecal samples from cattle (35 ) and poultry (19 ).…”

“…Our results imply a very high prevalence of DEC among patients; however, this difference may be attributable to the use of a sensitive multiplex real-time PCR protocol, and not because of an increase in the incidences of DEC infection over time. In addition, previous studies conducted in Bangladesh did not consider the virulence genes virB, afaB, and astA of the DEC pathotypes (14,16,21).…”

“…In previous studies, 45 or 34 of cases of acute diarrhea in Bangladeshi children have been found to be caused by DEC (13,14), and 34 of all diarrheal episodes in Bangladesh have been attributed to DEC (15). In Bangladesh, Albert et al (13) have examined SUMMARY: Using multiplex real-time PCR, 960 fecal samples collected from poultry, cattle, and patients with diarrhea in Bangladesh were screened for diarrheagenic Escherichia coli (DEC).…”

“…The small number of stx-positive patients could be explained by the small number of animal samples that were positive for both eae and stx. stool samples for DEC pathotypes and detected ETEC, EPEC, EAEC, and DAEC, while other researchers have isolated EPEC and ETEC (14) or only STEC (16). All these studies have been conducted only on hospitalized patients with diarrhea; stool samples from patients with diarrhea and domestic animals in Bangladesh have not been exhaustively examined for all DEC pathotypes.…”