Multiplex PCR Assay for Identification of Human Diarrheagenic Escherichia coli

A multiplex PCR assay was evaluated for diagnosis of diarrheagenic Escherichia coli in stool samples of patients with diarrhoea submitted to a diagnostic microbiology laboratory. Two procedures of DNA template preparationproteinase K buffer method and the boiling method were evaluated to examine isolates of E. coli from 150 selected diarrhoeal cases. By proteinase K buffer method, 119 strains (79.3%) of E. coli were characterized to various categories by their genes that included 55.5% enteroaggregative E. coli (EAEC), 18.5% enterotoxigenic E. coli (ETEC), 1.7% enteropathogenic E. coli (EPEC), and 0.8% Shiga toxin-producing E. coli (STEC). Although boiling method was less time consuming (<24 hrs) and less costly (<8.0 US $/ per test) but was less efficient in typing E. coli compared to proteinase K method (41.3% vs. 79.3% ; p<0.001). The sensitivity and specificity of boiling method compared to proteinase K method was 48.7% and 87.1% while the positive and negative predictive value was 93.5% and 30.7%, respectively. The majority of pathogenic E. coli were detected in children (78.0%) under five years age with 53.3% under one year, and 68.7% of the children were male. Children under 5 years age were frequently infected with EAEC (71.6%) compared to ETEC (24.3%), EPEC (2.7%) and STEC (1.4%). The multiplex PCR assay could be effectively used as a rapid diagnostic tool for characterization of diarrheagenic E. coli using a single reaction tube in the clinical laboratory setting.Bangladesh J Med Microbiol 2007; 01 (02): 38-42

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

Asian Journal of Medical Sciences ◽

10.3126/ajms.v5i2.8576 ◽

2013 ◽

Vol 5 (2) ◽

pp. 59-66 ◽

Cited By ~ 1

Author(s):

Sushmita Roy ◽

SM Shamsuzzaman ◽

Kazi Z Mamun

Keyword(s):

Escherichia Coli ◽

Multiplex Pcr ◽

Acute Diarrhea ◽

Tertiary Care ◽

Medical Science ◽

Pcr Assay ◽

E Coli ◽

Diarrheagenic Escherichia Coli ◽

Multiplex Pcr Assay ◽

Stool Samples

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

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