Prevalence, Virulence Factors And Drug Resistance Of Enteroaggregative Escherichia Coli Isolated From Children Under Five Years Old In Kiambu County Hospital

Enteroaggregative Escherichia coli (EAEC) is recognized as the leading bacterial pathogen in children hospitalized for acute diarrheal illness reflecting a significant cost in health resources. However, asymptomatic carriage of EAEC is also high making it difficult to distinguish the pathogenic and the non-pathogenic strains of EAEC. Establishing a marker which corresponds with diarrheal illness would be of significant value in routine detection of pathogenic EAEC and its differentiation from non pathogenic EAEC. The aim of this study was to determine the prevalence and identify the putative virulence factors of EAEC between children admitted with diarrhea and in age matched asymptomatic children under five years old. In this study, 354 fecal samples from diarrheal patients and 354 from asymptomatic controls collected during a case control study in Kiambu County, Kenya, were analyzed. Microbial culture and biochemical analysis were carried out for confirmatory identification of Escherichia coli (E. coli). At least five different colonies from each sample identified as E. coli were then examined by Multiplex-PCR for determination of EAEC and for the detection of the various putative virulence genes. Enteroaggregative Escherichia coli was detected in 60/354 (16.95%) diarrheal patients and 60/354 (16.95%) asymptomatic controls. Genes that encode a transcriptional regulator and E. coli heat-stable enterotoxin 1, aggR and astA, respectively, were detected significantly more in patients than in controls (P=0.0271 and 0.0443, respectively). Usher, aggregative adherence fimbriae (AAF) III/IV assembly unit, agg3/4C, was not detected in any EAEC strains from patients while 93.2% of the EAEC strains from asymptomatic controls were found positive for the gene.