Writing in the journal Clinical Infectious Diseases, a team of Italian and Indian researchers showed that prophylactic supplementation with Lactobacilli strains have by-products such as lactic acid and hydrogen peroxide that suppress common uropathogens.
In particular, Lactobacilli strains in the intravaginal probiotic formulation can produce anti-infective agents, the study reported.
“The probiotic bacteria adhere at high levels to human epithelial cells, displacing vaginal pathogens, exerting a bactericidal effect on some of the common opportunistic microorganisms of the female genital tract,” the researchers wrote.
Additionally, administering probiotic strains can restore the vaginal flora and reduce colonization of uropathogens, reducing the risk of infection.
The probiotic combination is proposed as alternative therapy to antibiotics, currently the primary treatment for recurrent UTIs in an era of widespread multidrug-resistant uropathogens.
This randomized, double-blind, placebo-controlled study was conducted at a teaching hospital in Chandigarh, India and included 174 premenopausal women aged 18–45 years with a history of three or more uncomplicated UTIs diagnosed within the previous year. The women agreed not to take antibiotics during the study period.
Researchers assigned participants to either an oral probiotic, vaginal probiotic, oral-vaginal probiotic combination or placebo group and tracked UTI symptoms during a one-year follow-up period.
Supplements used in the study included probiotic oral capsules (available as Visbiome and Florimax) and vaginal tablets (available as FloraBalance and Evanew), along with corresponding placebo preparations. Each probiotic oral capsule contained more than 112 billion live, lyophilized, lactic acid bacteria and bifidobacterial. The probiotic vaginal tablet contained one billion colony-forming units of a mix of three lactobacilli strains.
“The combination of vaginal and oral probiotics provided better results than the vaginal probiotic alone; however, there was no statistically significant difference between them,” the researchers wrote. “Maintaining a healthy microbiota in the vagina is a key strategy for reducing the risk of ascending infections in the urinary tract.”
The researchers also documented through a PCR test that there was less vaginal E. coli among the experimental groups as compared to the placebo, including in the oral probiotic group, “underlining the role of a healthy intestinal microbiota in the prevention of recurrent UTIs,” they noted.
Nearly half of all women will have at least one UTI during their lifetime, with prevalence rising with age. Sexual activity also increases vulnerability to the infection. Among women who experience UTIs, 20% to 30% will have a reoccurrence. This includes women who experience three occurrences of the infection in a 12-month period or a minimum of two episodes in a 6-month period.
“Probiotics avert or stop the ascension of uropathogens into the bladder through various mechanisms, including interference with pathogen adhesion, biofilm formation, invasion and growth, expression of virulence factors and modulation of the host’s defenses to fight infections,” the researchers wrote.
They added that the present study is among several clinical studies that demonstrate “the restoration of healthy vaginal flora, decreased vaginal coliform counts and reduced UTI recurrence rates with oral and vaginally administered probiotics.”
Source: Clinical Infectious Diseases
“Effectiveness of Prophylactic Oral and/or Vaginal Probiotic Supplementation in the Prevention of Recurrent Urinary Tract Infections: A Randomized, Double-Blind, Placebo-Controlled Trial”
Authors: Varsha Gupta et al.