Specific strains of extraintestinal pathogenic Escherichia coli are a common cause of bacteremia and sepsis following post transrectal ultrasound (TRUS)-guided prostate biopsy and urinary tract infections (UTI). The ability of these strains to successfully survive and replicate in human serum is yet to be fully understood. Among these virulent strains, the most important currently is E. coli sequence type 131 (ST131), which is a globally disseminated and highly resistant pandemic clone. ST131 has been the dominant E. coli strain in terms of community and hospital-acquired urinary tract and bloodstream infections worldwide in recent years. While UTI associated strains and TRUS associated strains show similar resistant to human serum, they differ in their virulence markers, suggesting that they are genetically distinct, and some of them belong to the same clonal complex as ST131 but differ in their plasmid content. The aim of this study is to compare different E. coli clinical isolates responsible for post-TRUS biopsy infections and bacteremic urinary tract infection, and to analyze them using a combination of genome sequencing, serum resistance phenotyping and genetic analysis by mutagenesis.
