D-Mannose to prevent Recurrent UTI: a double blind randomised placebo controlled trial

Recurrent Urinary Tract Infections (RUTIs), where patients experience three or more UTIs in a year, or two in 6 months, affect about 800,000 women in the UK annually. RUTIs impact considerably on quality of life, and affected women are usually prescribed frequent antibiotic courses or continuous antibiotics. This increases the risk of side effects and the chance that subsequent UTIs are antibiotic resistant, which are harder to treat and cause prolonged, more severe symptoms.

D-Mannose is a form of sugar that may prevent UTIs through preventing bacteria from attaching to the bladder lining. A Croatian study in outpatient clinics recently showed that daily D-mannose worked better than either daily antibiotics or no treatment to prevent further UTIs. However, the 309 participants knew which treatment they were having, which could have influenced their perception of UTI symptoms, and many women with relevant symptoms were excluded. Two further small studies showed a benefit, but recruited women from hospital clinics, so the results may not apply to women treated in primary care.

We therefore plan to recruit 508 women with RUTI in primary care. Half will be assigned at random to take a daily dose of D-mannose for 6 months; the other half will receive a matched placebo. Women who suffer with RUTI have told us that the most important outcome for them is a reduced chance of having further UTIs bad enough to require medical attention. We will therefore compare the proportion of women seeking medical attention for UTI between those taking regular D-mannose and those taking placebo. We will also compare the number of days of moderately bad symptoms, antibiotic use, and the number of antibiotic resistant infections. We will ask women about their experiences of a daily preventative treatment, and assess whether D-mannose offers value for money in preventing RUTIs.