Combination of cranberry extract and D-mannose - possible enhancer of uropathogen sensitivity to antibiotics in acute therapy of urinary tract infections: Results of a pilot study

Exp Ther Med. 2020 Oct;20(4):3399-3406. doi: 10.3892/etm.2020.8970. Epub 2020 Jul 7.


Uncomplicated lower urinary tract infections are extremely common in women. Antibiotic treatment for acute episodes and for recurrence prophylaxis has its drawbacks and alternative therapies are sought in order to reduce the antimicrobial resistance phenomenon and the intestinal dismicrobism expansion. There are few studies on the effect of combination of cranberry extract with D-mannose in acute urinary tract infection management. In a pilot, randomized study 93 non-pregnant, otherwise healthy women, were enrolled with mean age of 39.77±10.36, diagnosed with uncomplicated lower urinary tract infection. Medical history, clinical examination, urine culture and a list of complaints were noted at the baseline visit. In a first phase of the study, treatment with either guideline recommended antibiotic alone or in association with the investigated product (cranberry extract plus D-mannose) was prescribed and all patients were clinically examined at day 7. All ameliorated and cured patients received in a second phase of the study, in a double-blind manner, prophylaxis with the investigated product or placebo for another 21 days, then a second clinical examination and a check of the list of complaints were performed. The cure rates were higher at day 7 when investigated product was added to antibiotic (91.6 vs. 84.4%). In resistant strains, a significantly higher cure rate was shown when the investigated product was added to antibiotic prescribed (88.8 vs. 37.5%, P<0.0001). The effect of cranberry extract plus D-mannose combination in acute urinary tract infection episodes seems to be promising. The significant cure rate registered in the patients with antibiotic-resistant urine cultures may be explained by a beneficial influence of the product on the antimicrobial sensitivity. Further studies are needed on this subject.

Keywords: Cranberry extract; D-mannose; antibiotic; lower urinary tract infection; sensitivity to antibiotics.