Urinary tract infections (UTIs) can be hard to shake.
The chance of recurrence after the first episode in healthy 18–29 year-old women has been reported as 24%. Unfortunately, the traditional treatment of antibiotics may cause resistance. For this reason, other therapies are being explored.
Microbial Shift in UTIs
First indication: Studies of the urinary microbiota show marked differences between healthy populations and those with urologic diseases. Depletion of certain organisms in those with recurring UTIs points to a possible role for probiotics to replenish a healthy milieu and thus lower infections.
Thanks to recent sequencing and quantitative urine culture techniques developed in recent years, bacteria colonized in normal flora in the urinary system have been detected.
Lactobacillus and Streptococcus are the dominant microbes. Both organisms are lactic acid bacteria that protect against pathogens colonized in the urogenital region. See this Table listing urinary microbiomes in healthy women.
Importantly, UTI recurrence can lead to the shift of Lactobacillus dominancy in the normal flora to uropathogens.
Probiotics and UTIs: What to Know
Many studies have shown that probiotic support may intervene in genitourinary infections.
The role of probiotics in women with recurrent urinary tract infections does a nice job of recapping probiotics interventions and relative success rates. It appeared in the Turkish Journal of Urology.
Notably, probiotics that prevent and treat genitourinary infections should contain Lactobacillus species.
How do they operate?
- Produce hydrogen peroxide and biosurfactants that acidify the vaginal mucosa.
- Inhibition of adhesion of pathogens
- Production of substances such as vitamins and immunomodulators
- Synergistic activity with the immune system
One meta-analysis using 294 patients from five studies showed the safety and efficacy of Lactobacillus in preventing recurrent UTIs in adult women. Combinations of strains of L.crispatus or L. rhamnosus and L.fermentum were the most effective but others also had success as seen in Table 3 in the paper.
As expected, dose and formulations of probiotics were diverse: doses varied between 104 CFU and 1010 CFU; oral, vaginal, and liquid formulations were used; duration ranged from 5 days to 12 months; single as well as combinations were used.
Thus, the authors caution that evidence for prevention and treatment are far from definitive. To achieve clarity, larger trials with outcomes defining types, numbers and associated growth factors are needed for standardization.
In the literature, probiotic interventions were shown to have some efficacy in the treatment and prevention of urogenital infections. Despite previous controversy regarding the use of probiotics, as treatment for UTIs, there are increasing signs that it may be possible to use them as a first step in regulating the UM so as to reduce the risk of or as a treatment for certain urinary diseases.Akgül T, Karakan T. The role of probiotics in women with recurrent urinary tract infections. Turk J Urol. 2018;44(5):377–383. doi:10.5152/tud.2018.48742