Effect of Probiotics on Recurrent Urinary Tract Infections

Efficacy of a Food Supplement for the Treament of Recurrent Urinary Tract Infections

Randomized clinical trial to evaluate the effect of a probiotic mixture of Lactobacillus plantarum on recurrent urinary tract infections in women. Secondary outcomes comprise variation in vaginal/perianal microbiota, product tolerability, safety and consumer's satisfaction with the product.

Double-blind, randomized, placebo-controlled clinical trial to determine the effect of two probiotic strains of Lactobacillus plantarum on recurrent urinary tract infections in women. Women are randomized 1:1 to one of the following study groups: one group will receive a capsule/day of the mixture of Lactobacillus plantarum in combination with cranberry, and vitamine C; and the other group will receive a capsule of placebo for 6 months. Main study outcome is the number of women who have recurrence of UTIs during th estudy compared to the placebo group. Secondary outcomes comprise the duration of disease free period, duration and severity of symptomatology, the number of symptomatic UTIs during the study, variation of Lactobacillus plantarum levels in the vaginal/perianal microbiota, product tolerability, safety and consumer's satisfaction with the product.

Inclusion Criteria:

• Women over 18 years of age.
• Women who have had at least one episode of UTI in the past 4 months
• Women with a well-documented history of recurrent UTIs: ≥2 infections in the past 6 months or ≥3 in the past 12 months.
• Women who have been treated with an antibiotic regimen for each episde of UTI
• Recurrence due to reinfection, not relapse: multiple infections should be spaced by a minimum of 2 weeks or in case of a shorter time, with negative urine culture between them
• Women who use contraception to prevent pregnancy and who do not plan a pregnancy during the study period

Exclusion Criteria:

• Pregnant or breastfeeding women
• Underlying chronic disease: diabetes mellitus, kidney failure, cancer, spinal cord injury, polycystic ovary
• Women wih catheters in the urethra
• Women who consume probiotics or foods, beverages or supplements containing extracts or parts of the genus Vaccinum sp, including other forms of V. macrocarpon (blueberry), V. myrtillus (European blueberry), V. angustifolium (wild or low buch blueberry), V. corymbosum (tall bch blueberry) or V. vitis-ideae (mountain blueberry) during the 2 weels prior to recruitment.
• High consumption of fruits rich in phenolic compounds, with special reference, to berries
• Women allergic to red fruits