Prevalence, Virulence Gene Profiling, and Characterization of Enteroaggregative Escherichia coli from Children with Acute Diarrhea, Asymptomatic Nourished, and Malnourished Children Younger Than 5 Years of Age in India

Vinay Modgil; Pankaj Chaudhary; Bhavneet Bharti; Jaspreet Mahindroo; Md Yousuf; Meenakshi Koundal; Balvinder Mohan; Neelam Taneja

doi:10.1016/j.jpeds.2021.03.010

Prevalence, Virulence Gene Profiling, and Characterization of Enteroaggregative Escherichia coli from Children with Acute Diarrhea, Asymptomatic Nourished, and Malnourished Children Younger Than 5 Years of Age in India

J Pediatr. 2021 Jul:234:106-114.e5. doi: 10.1016/j.jpeds.2021.03.010. Epub 2021 Mar 11.

Authors

Vinay Modgil¹, Pankaj Chaudhary², Bhavneet Bharti², Jaspreet Mahindroo¹, Md Yousuf¹, Meenakshi Koundal¹, Balvinder Mohan¹, Neelam Taneja³

Affiliations

¹ Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
² Department of Pediatrics Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
³ Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh, India. Electronic address: drneelampgi@yahoo.com.

PMID: 33713662
DOI: 10.1016/j.jpeds.2021.03.010

Abstract

Objective: To study the significance of enteroaggregative Escherichia coli (EAEC) as a pathogen causing acute diarrhea and a commensal in healthy nourished and malnourished children younger than five years of age in the Chandigarh region and to address possible traits of EAEC virulence genes, biofilm formation, phylogroups, and antibiotic resistance that would be correlated with diarrhea or carriage.

Study design: Stool samples were obtained from children with acute diarrhea (n = 548), as well as nourished (n = 550), and malnourished controls without diarrhea (n = 110). E coli isolates were confirmed as EAEC by pCVD432 polymerase chain reaction. Multiplex polymerase chain reactions were used to identify 22 virulence-related genes and phylogeny. Antibiotic susceptibility, adherence, and biofilm-forming potential also were studied.

Results: Overall, 16.6% of children were malnourished. EAEC detection was greater among children with acute diarrhea (16%) than nourished (6%) and malnourished nondiarrheal controls (2.7%). We found an association of EAEC infections with age <2 years (P = .0001) in the diarrheal group. Adhesive variants adhesion fimbriae IV and adhesion fimbriae II were significantly associated with diarrhea. The aggR and aar genes showed a positive and negative association with the severity of disease (P = .0004 and P = .0003). A high degree of multidrug resistance was found (73.8%) in the diarrheal group. Most EAEC strains from the diarrheal group belonged to B2 and D phylogroups, whereas strains from non-diarrheal groups, which belonged to phylogroup B1.

Conclusions: EAEC is a significant contributor to childhood diarrhea, its presence as a commensal, and the significance of the association of various virulence factors among the EAEC isolated from diarrheal and non-diarrheal stools. These data reinforce the importance of aggR and aar as positive and negative regulators and the contribution of AAF/II and AAF/IV fimbria for the pathobiology of EAEC.

Keywords: enteroaggregative Escherichia coli; malnutrition; multiplex PCR; phylogeny; virulence genes.

MeSH terms

Case-Control Studies
Child, Preschool
Diarrhea / epidemiology
Diarrhea / microbiology*
Drug Resistance, Multiple
Escherichia coli / isolation & purification
Escherichia coli Infections / epidemiology*
Female
Humans
India / epidemiology
Infant
Infant, Newborn
Male
Malnutrition / epidemiology*
Multiplex Polymerase Chain Reaction
Prevalence
Virulence Factors

Substances

Virulence Factors