Bladder Microbiomes Altered in Women With Urinary Incontinence

By Anne Harding

May 14, 2020

NEW YORK (Reuters Health) — Bladder bacterial diversity is different for women with urinary incontinence (UI) compared to unaffected women, according to a new cross-sectional study.

"We don't know if it's the chicken or the egg, but now that we know there's a difference we can begin to do research to understand why that difference is there and whether that difference offers opportunities for new ways of treating patients or better ways of diagnosing or characterizing the problem," Dr. Linda Brubaker of the University of California, San Diego, told Reuters Health by phone.

Researchers have learned in recent years that the bladder is home to a microbial community, or urobiome, and is not a sterile environment, Dr. Brubaker noted. "In non-pregnant women, it's not helpful, and probably is harmful, to give antibiotics to try to sterilize the bladder."

She and her colleagues compared the bladder urobiomes of 50 women with stress urinary incontinence (SUI), 109 with urgency urinary incontinence (UUI) and 150 controls without UI. They cultured bacteria from 70% of urine samples.

Lactobacillus iners (12.7%), Streptococcus anginosus (12.7%), L. crispatus (10.7%) and L. gasseri (10%) were the most frequently detected species in controls, the team reports in the American Journal of Obstetrics and Gynecology.

For the SUI group, S. anginosus (26%), L. iners (18%), Staphylococcus epidermis (18%) and L. jensenii (16%) occurred most frequently. Species most common in UUI were S. anginosus (30.3%), L. gasseri (22%), Aerococcus urinae (18.3%) and Gardnerella vaginalis (17.4%).

The only species to be found at significantly higher abundance in the UI groups than the control group were Actinotignum schaalii, A. urinae, A. sanguinicola, and Corynebacterium lipophile group. There were no differences between the two UI groups in any individual genus of bacteria.

Microbial communities in the control group were less rich than in either of the UI groups, while evenness was similar. Urobiome richness correlated with incontinence severity based on Urinary Distress Inventory scores.

Dr. Brubaker and her colleagues now plan to look at the urobiomes of healthy women over time. A better understanding of the urobiome "should hopefully refine and improve our use of antibiotics," she said. "We'll probably be able to make some pretty good breakthroughs for better diagnosis, prevention and treatment as we learn more about the urobiome."

SOURCE: American Journal of Obstetrics and Gynecology, online May 4, 2020.