Recurrent Urinary Tract Infections in Adult Women: a Pilot Study With Oral D Mannose

INTRODUCTION Urinary tract infections (UTIs) are among the most common infectious diseases, with a substantial financial burden to society. In Europe data on the presence of various types of UTIs indicate a high impact on quality of life of people affected, it is important the impact of urinary tract infections on the economy in general and on the health system in particular. In the U.S. urinary tract infections account for more than 7 million doctor visits each year, including more than 2 million visits for cystitis. The bacterium E. coli, which is the source of 90% of urinary tract infections, shows an incredible ability to survive in the human body, and is able to change rapidly to survive antibiotics. An infection of the urinary tract must be stopped before it begins to migrate to the kidneys, where it can cause serious infections. Women with frequent reinfections have a rate of 0.13 to 0.22 UTIs per month (1.6 to 2.6 infections per year). For premenopausal, healthy, and active females, recurrent UTIs are a major healthcare concern. Recurrent urinary tract infection (RUTI) is defined as three episodes of urinary tract infection (UTI) with 3 positive urine cultures in the previous 12 months or two episodes in the last six months. The usual present strategies employing a prophylactic antibiotic regime to prevent recurrent UTIs include long-term low-dose prophylactic antimicrobial treatment or postcoital antibiotic treatment. However, it seems that these strategies do not alter the long-term risk of recurrence. Patients with frequent UTIs who take prophylactic antimicrobial agents for extended periods decrease their infections during prophylaxis, but the rate of infection returns to pre-treatment rates when prophylaxis is stopped . Long-term antibiotics do not appear to positively affect the patient's basic susceptibility to infections. The cell wall of E. coli bacteria has tiny finger-like projections that contain complex molecules called lectins on their surface. These lectins act as a cellular glue that binds the bacteria to the bladder wall so they cannot be easily rinsed out by urination . In this pilot study the aim was to evaluate if oral D Mannose could be used as a safe and effective treatment and as a prophylactic measure for recurrent UTIs in adult women.

PATIENTS AND METHODS Suitable female patients with recurrent urinary tract infections who were visited at the outpatient Clinic of our Urology Department were eligible for study. The work has been conducted in accordance with the principles of the Declaration of Helsinki of World Medical Association. Patients were enrolled in the study after treatment for the most recent urinary tract infection if they had positive urinary cultures at that time.

Each participant entering the trial was assigned to one of the following treatments in a random sequence:

1. A regimen of five-day antibiotic therapy with trimethoprim/sulfamethoxazole 160 mg/800 mg twice a day. Then 1 week of antibiotic every 4 weeks for the following 23 weeks
2. A regimen of oral D Mannose 1 gr. 3 times a day, every 8 hours for 2 weeks, and subsequently 1 gr. twice a day for 22 weeks. D-Mannose has the best activity when urine has neutral pH, therefore patients were instructed to measure urinary pH using dipsticks and use oral sodium bicarbonate 250 mg b.i.d.or potassium citrate 1 gr. b.i.d. as alkalinizing agents if pH was <7.

Patients were randomly assigned to antibiotic treatment with trimethoprim/sulfamethoxazole or to a regimen of oral D Mannose for 24 weeks, and received the other intervention in the second phase of the study.