Gut uropathogen abundance is a risk factor for development of bacteriuria and urinary tract infection

The origin of most bacterial infections in the urinary tract is often presumed to be the gut. Herein, we investigate the relationship between the gut microbiota and future development of bacteriuria and urinary tract infection (UTI). We perform gut microbial profiling using 16S rRNA gene deep sequencing on 510 fecal specimens from 168 kidney transplant recipients and metagenomic sequencing on a subset of fecal specimens and urine supernatant specimens. We report that a 1% relative gut abundance of Escherichia is an independent risk factor for Escherichia bacteriuria and UTI and a 1% relative gut abundance of Enterococcus is an independent risk factor for Enterococcus bacteriuria. Strain analysis establishes a close strain level alignment between species found in the gut and in the urine in the same subjects. Our results support a gut microbiota–UTI axis, suggesting that modulating the gut microbiota may be a potential novel strategy to prevent UTIs. Urinary tract infections (UTIs) are associated with changes in the gut microbiome. Here, the authors evaluate the relationship between the gut microbiome and development of UTI in kidney transplant patients and show that uropathogenic gut abundance might represent a risk factor for development of bacteriuria and UTI.