Recurrent urinary tract infection and estrogen shape the taxonomic ecology and functional potential of the postmenopausal urobiome

Abstract

Community-acquired urinary tract infection (UTI) is among the most common bacterial infections observed in humans. Postmenopausal women are a rapidly growing and underserved demographic group who are severely affected by recurrent UTI (rUTI) with a >50% recurrence rate. In this population, rUTI can persist for years, reducing quality of life and imposing a significant healthcare burden. rUTI is most often treated by antibiotics, but development of antibiotic resistance and allergy limit therapeutic options. The female urinary microbiome (urobiome) has been identified as a key component of the urogenital environment. However, compositional and functional changes in the urobiome underlying rUTI susceptibility in postmenopausal women are not well understood. Here, we used a controlled, cross-sectional cohort of postmenopausal women, to interrogate changes in urobiome structure and function linked to rUTI susceptibility by whole genome metagenomic sequencing (WGMS), advanced urine culture, estrogen metabolite profiling, and antibiotic sensitivity testing. Overall, we detected 276 bacterial, archaeal, and fungal species representing 106 genera. We find a putative commensal population consisting of species known to protect against bacterial vaginosis, such as Lactobacillus crispatus, within the urobiome of postmenopausal women who do not experience UTI. Integration of clinical metadata detected an almost exclusive enrichment of lactobacilli, including L. crispatus and L. vaginalis, in women taking estrogen hormone therapy (EHT). Integrating quantitative metabolite profiling of urinary estrogens with WGMS, we observed robust correlations between urobiome taxa, such as Bifidobacterium breve and L. crispatus, and urinary estrogen conjugate concentrations in women with no history of UTI that were absent in women with rUTI history. We further used functional metagenomic profiling and patient-derived isolate phenotyping to identify microbial metabolic pathways, antimicrobial resistance genes (ARGs), and clinically relevant antimicrobial resistance phenotypes enriched between disease-states. Our data indicate that distinct urobiome metabolic and ARG signatures are associated with current rUTI status and history. Importantly, we observed that rUTI history leaves an imprint of enriched ARGs even in women not currently experiencing UTI. Taken together, our data suggests that rUTI history and estrogen strongly shape the functional and taxonomic composition of the urobiome in postmenopausal women.