Evaluation of the Presence of fimH and bfpA Genes in Escherichia coli Isolated from Pregnant Women

  Escherichia coli (E. coli) is one of the most abundant bacteria in human and animal infections. Many virulence genes in E. coli intensify its infectivity. This study explored the presence of two pathogenic genes, including fimH and bfpA, in E. coli strains isolated from pregnant women.

From autumn 2016 to spring 2017, a total of 100 E. coli isolates were collected from clinical samples (116) of pregnant women. The strains were identified using biochemical tests (catalase, Simmons citrate, indole, mobility, H2S, MR, VP, TSI, and urease). The presence of pathogenic genes in these isolates was examined using colony PCR method. Finally, the relationship between the gene and the site of infection was analyzed in SPSS-23 software. 

PCR results indicated that out of 100 E. coli samples, 15 were bfpA positive (15%), and 64 were fimH positive (64%). A significant relationship was found between the presence of bfpA gene and samples taken from urine (p<.001), blood (p=.049), and stool (p<.001). 

None of the urinary strains harbored the bfpA gene, while the strains isolated from stool had a significant relationship with the presence of bfpA gene (OR = 18.667), which confirms that this gene is of great importance for EPEC (enteropathogenic E. coli). There was also a significant relationship between blood-isolated strains and the presence of bfpA gene. A significant relationship was also found between the fimH gene and strains isolated from urine samples (OR=36.733), while no relationship was observed between the presence of fimH gene and blood-isolated strains.