Diarrheagenic Escherichia coli Pathotypes From Children Younger Than 5 Years in Kano State, Nigeria.

Habeeb Kayode Saka,Maria Ugarte-Ruiz,Julio Alvarez,Bashir Muhammad,Silvia García-Soto,Nasir Tukur Dabo

doi:10.3389/fpubh.2019.00348

Abstract

Diarrheagenic Escherichia coli (DEC) is one of the leading causes of gastrointestinal disorders worldwide and an important public health challenge. DEC infection is often underdiagnosed during routine microbiological analysis, especially in resource constrained settings; the use of molecular tests could however help to determine the distribution of DEC and its clinical significance. Here, a study to assess the prevalence of DEC in clinical samples from patients <5 years attending three hospitals in Kano state, Nigeria, was carried out. Samples from 400 patients and 50 controls were collected and screened for E. coli. Compatible colonies from 248 individuals (215 patients and 33 controls) were characterized using biochemical test, a set of real-time PCRs for detection of nine virulence factors (VF: eae, bfpA, elt, est, stx1, stx2, ehxA, aggR, and invA) associated with five DEC pathotypes (EPEC, ETEC, EHEC, EAEC, and EIEC) and antimicrobial susceptibility tests. One or more VFs typical of specific pathotypes were detected in 73.8% (183/248) of the isolates, with those associated with EAEC (36.3%), ETEC (17.3%), and EPEC (6.0%) being the most common, although proportion of specific pathotypes differed between hospitals. est was the only VF detected in a significantly higher proportion in cases compared to controls (P = 0.034). Up to 86.9% of DEC were resistant to at least one class of antibiotics, with trimethoprim-sulfamethoxazole being the least effective drug (77.6% resistance). Our results demonstrate the widespread circulation of different DEC pathotypes that were highly resistant to trimethoprim-sulfamethoxazole among children in Kano state, and highlight the need of characterizing the causative agents in cases of gastrointestinal disorders.

Highlights

Enteric infections and diarrheal diseases (EIDD) constitute a pervasive health burden throughout the world [1,2,3], closely associated with poor water supply, sanitation and hygiene status, which are common in developing countries [1]
This study investigated the occurrence and frequency of Diarrheagenic Escherichia coli (DEC) as a cause of infectious diarrhea in children younger than 5 years in Kano, along with their antibiotic susceptibility pattern, to provide baseline data on the circulating DEC pathotypes in Kano and on their clinical significance
In this study we determined the frequency of detection of virulence factors (VF) associated with DEC pathotypes in a subset of isolates recovered from children below 5 years with and without clinical symptoms compatible with a DEC infection in an attempt to establish their clinical significance

Summary

Introduction

Enteric infections and diarrheal diseases (EIDD) constitute a pervasive health burden throughout the world [1,2,3], closely associated with poor water supply, sanitation and hygiene status, which are common in developing countries [1]. Diarrhea is characterized by stools of decreased consistency and increased volume due to imbalance of secretion and absorption of water and salts in the intestine [5] It is a major source of malnutrition and life threatening diseases which may be fatal [6, 7]. E. coli is a Gram-negative, oxidase-negative, rodshaped bacterium from the family Enterobacteriaceae [9] that is encountered as a normal inhabitant of human and other mammalian intestine [10]. It colonizes the gastrointestinal tract of new-born infants within few hours after birth [11] and is readily isolated from fecal samples. E. coli strains carrying certain VFs have been recovered from healthy human controls, demonstrating that the presence of certain VFs does not necessarily imply their involvement in clinical disease [14]

Methods

Results

Conclusion