Bacterial genome wide association study substantiatespapGIIofEscherichia colias a patient independent driver of urosepsis

Abstract

Abstract Urinary tract infections are extremely common and often caused by Escherichia coli . Bacterial virulence factors and patient characteristics have been linked separately to progressive, invasive infection. The interaction of these factors has however rarely been considered. We whole genome sequenced 1076 E. coli isolates recovered from urine-or blood culture samples from 825 clinical cases. The majority of isolates belonged to the phylogroups B2 and D and encoded polysaccharide capsules. In line with previous studies, our bGWAS identified papGII to be associated with bacteraemia. In a generalised linear model correcting for patient characteristics, papGII was substantiated as a major contributor to invasive infection. Further, an independent cohort of 1,657 urine samples was PCR screened for papGII carrying E. coli , confirming the increased relative frequency of papGII + strains to cause invasive infection. This study builds on previous work linking papGII with invasive infection by showing that it is a patient-independent risk factor that has diagnostic potential.