Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jul;23(7):915-921.
doi: 10.22038/ijbms.2020.42119.9959.

Genotypic and phenotypic characterization of enteroaggregative Escherichia coli (EAEC) isolates from diarrheic children: An unresolved diagnostic paradigm exists

Haiffa Helalat  1 , Seyedeh Elham Rezatofighi  1 , Mohammad Roayaei Ardakani  1 , Luis Fernando Dos Santos  2 , Mahdi Askari Badouei  3
Affiliations

Genotypic and phenotypic characterization of enteroaggregative Escherichia coli (EAEC) isolates from diarrheic children: An unresolved diagnostic paradigm exists

Haiffa Helalat et al. Iran J Basic Med Sci. 2020 Jul.

Abstract

Objectives: 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 laboratories.

Materials and methods: In this study, we analyzed and compared 36 typical EAEC strains (aggR-positive) by various genotypic and phenotypic methods.

Results: Briefly, pCVD432 was detected in all of isolates along with aggR, then it was followed by other virulence genes including app, astA, aggA, and pet genes in 32 (88.8%), 21 (58.3%), 9 (25%), and 2 (5.5%) isolates, respectively. Biofilm was formed by 34 (94.4%) isolates, while only 26 (72.2%) isolates showed an aggregative adherence pattern to HEp-2 cells.

Conclusion: The genetic and phenotypic features of EAEC were highly inconsistent, which may have considerable diagnostic implications. The variations in the virulence genes, phenotypic characteristics, and genetic profiles among the EAEC isolates again emphasized the genetic heterogeneity of this emerging pathotype. Biofilm formation may be an important phenotypic virulence property of this pathotype, especially in strains with the aggR-pCVD432-aap-astA profile.

Keywords: Aggregative adherence; Biofilm; Diagnosis; Diarrhea; Enteroaggregative-Escherichia coli; Virulence genes.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Enterobacterial repetitive intergenic consensus (ERIC) dendrogram and characteristics of enteroaggregative Escherichia coli (EAEC) isolates causing diarrhea in children
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Sukkua K, Patungkaro W, Sukhumungoon P. Detection and molecular characterization of enteroaggregative Escherichia coli from diarrheal patients in tertiary hospitals, southern Thailand. Southeast Asian J Trop Med Public Health. 2015;46:901–910. - PubMed
    1. Haghi F, Zeighami H, Hajiahmadi F, Khoshvaght H, Bayat M. Frequency and antimicrobial resistance of diarrhoeagenic Escherichia coli from young children in Iran. J Med Microbiol. 2014;63:427–432. - PubMed
    1. Kubomura A, Misaki T, Homma S, Matsuo C, Okabe N. Phenotypic and molecular characterization of enteroaggregative Escherichia coli isolated in Kawasaki, Japan. Jpn J Infect Dis. 2017;70:507–512. - PubMed
    1. Harrington SM, Dudley EG, Nataro JP. Pathogenesis of enteroaggregative Escherichia coli infection. FEMS Microbiol Lett. 2006;254:12–18. - PubMed
    1. Nataro JP, Steiner T, Guerrant RL. Enteroaggregative Escherichia coli. Emerg Infect Dis. 1998;4:251–261. - PMC - PubMed

LinkOut - more resources