Daily and Weekly Fluctuations in the Microbiome of the Urinary Tract of Postmenopausal Women with No History of Urinary Tract Infections

At least half of all women will experience a urinary tract infection (UTI) in their lifetime. Age, sexual activity, hormonal status, and the urinary tract microbiome (urobiome) contribute to the probability of infection. While studies have assessed urobiome composition during and after infection, no study has tracked the daily and weekly fluctuations of healthy urobiomes to determine urobiome stability. In this study, we sampled the clean catch urine of 3 women with no history of UTIs over the span of two weeks sampling three times a day on two days each week to track urobiome changes, and whether the urobiome in individuals with no UTI history resembles that of individuals after a UTI. Two participants were dominantly colonized by Lactobacillus while the third had a more diverse set of taxa albeit at a lower total amount of bacteria. We previously reported that the urine from only one of the less diverse urobiomes supported the growth of recently isolated uropathogenic Escherichia coli or Enterococcus faecalis, while the other two participants urines did not support growth. We conclude that 1) urobiomes exist in healthy post-menopausal women 2) these urobiomes have a stable and robust community structure and 3) a combination of colonization resistance, including nutrient limitation, and urobiome structure contributes to resistance to UTIs. ImportancePresented here is the first analysis of urinary tract microbiomes (urobiome) of post-menopausal women with no history of urinary tract infections collected at multiple times. These data contribute to the growing understanding of urobiomes of post-menopausal women during a healthy state. Minimal fluctuations were observed on an individual basis, confirming that the time of day or day of the week has no impact on the findings in longitudinal urine sample studies.