Distribution of Pathogenicity Island Markers and Virulence Factors Genes of Extraintestinal Pathogenic Escherichia coli Isolates

Abstract

Background: Extraintestinal pathogenic Escherichia coli (ExPEC) can colonize the urinary system with various virulence factors. Escaping from the host defense, can lead to serious infections, such as bacteremia and sepsis. Objectives: This study aimed to investigate the presence of phylogenetic groups, various virulence factor genes, and pathogenicity island (PAI) markers of extraintestinal and commensal E. coli isolates. Methods: Within January 2016 and December 2017, 50 E. coli isolates were isolated from simultaneous blood and urine samples of 25 patients hospitalized in Mersin University Faculty of Medicine, Turkey, and 50 commensal E. coli isolates were isolated from fecal 18 samples of healthy volunteers as the control group was included in the study. Phylogenetic groups, virulence factors genes, and PAI markers were determined by the multiplex polymerase chain reaction method. Results: The majority of ExPEC isolates were observed to be in phylogenetic group B2. All of the commensal E. coli isolates were detected in phylogenetic group A. The most predominant virulence factor gene was traT (80%). The most prevalent PAI marker was PAI IV536 (86%). However, the PAI I536, IJ96, and IIJ96 markers were not detected in any isolates. Only PAI IV536 was detected in commensal E. coli isolates. Conclusions: It was determined that E. coli isolates that cause uropathogenic and bloodstream infections contain a higher frequency of PAI than commensal isolates.