D-mannose for preventing and treating urinary tract infections in adults and children

Tags: Poster
Cooper T1, Teng C1, Howell M1, Teixeira-Pinto A1, Tong A1, Wong G1
1Cochrane Kidney and Transplant Review Group

Background: Urinary tract infections (UTI) are common in global populations. Approximately 50% of females experience an episode in their life and 20% of adults and children suffer chronic symptomatic UTIs (≥2 episodes in 6 months or 3 in 12 months). Long-term antibiotics may to lead to antibiotic resistance, adverse effects, significant patient burden and health costs. D-mannose is a sugar part of normal human diets that plays a role in the glycosylation of most secretory proteins. It attaches to bacteria, prevents adherence to the urothelial cells, and may have a role in the prevention and treatment of UTI in at-risk individuals.

Objectives: To assess the benefits and harms of D-mannose for preventing and treating urinary tract infections in adults and children, in any setting.

Methods: We searched the Cochrane Kidney and Transplant Register (which includes CENTRAL, MEDLINE, Embase, and ICTRP) to 1 March 2020 for RCTs of D-mannose in any formula, route. There were no restrictions on language, dates, or blinding. Screening, data extraction and analyses were performed by 3 independent reviewers. Outcomes: presence, or recurrence, of symptomatic bacteriuria UTI, symptomatic UTI, asymptomatic bacteriuria; any changes to previous treatment; and pain.

Results: 6 RCTs (704 adults) were included (Figure 1). Interventions varied in dose and frequency: D-mannose (2 RCTs), D-mannose plus vitamins (4 RCTs); antibiotics; vitamins; placebo; no treatment.

Risk of bias was judged for the 6 included studies overall to be at high risk (Figure 2). Most concerns around the lack of allocation concealment and blinding (open-label studies), or limited details in abstracts.

No two studies investigated comparable intervention arms, so no meta-analysis was undertaken (Table 1). Separately, studies reported some improvement from D-mannose (Table 2): D-mannose plus vitamins found a slightly lower incidence of recurrent cystitis compared to other combinations of D-mannose plus vitamins at 3 months (N=92). D-mannose plus vitamins found no difference in UTI incidence compared to vitamins at 6 months (N=95). D-mannose plus vitamins found a difference in reduction of UTI compared to placebo at 3 months (N=31). Both D-mannose and antibiotics compared to no treatment found a lower incidence of recurrent UTI, but no difference in mean time to UTI at 6 months (N=308). D-mannose found a difference in time to UTI compared to antibiotics at 6 months (N=60). 37 participants reported diarrhoea, with some nausea, headache, skin rash, and vaginal burning.

For all comparisons and outcomes, GRADE was rated as very low certainty evidence, downgraded twice for very serious limitations to study design (high risk of bias), and once for sparse data (Table 3).

Conclusions: There is no evidence to support or refute the use of D-mannose to prevent or treat UTIs in adults and children. Further high-quality research through RCTs, is required to evaluate the benefits and harms.