Several studies, reviews and meta-analyses have documented that
D-mannose use lowers the risk of recurrent
urinary tract infections (UTI), but its role in the treatment of UTI/
cystitis-related symptoms is unclear. In particular, no systematic review has analyzed the role of treatment with
D-mannose in acute UTI/
cystitis. In this paper, we systematically reviewed the published data on the effect of
D-mannose, alone or in association with other compounds, on the typical symptoms of UTI/
cystitis. PubMed/Medline and EMBASE databases were searched, from 1990 to January 2022, using combinations of the following keywords: '
urinary tract infections', 'cystalgia', 'recurrent next
urinary tract infection', '
cystitis', '
mannose', '
mannoside', '
D-mannose', '
bacteriuria', '
pyuria', '
pyelocystitis' with the appropriate Boolean modifiers (Limits: Human, English, full article). Studies were selected for the systematic review if they were clinical studies and reported original data, the number of patients using
D-mannose alone or in association with other treatments, and the number of patients with symptoms of UTI/
cystitis at trial entry and after the follow-up period. A total of seven studies were identified.
D-mannose was given alone in two studies, and was associated with cranberry extract, Morinda citrifolia fruit extract, pomegranate extract, fructo-
oligosaccharides, lactobacilli, and
N-acetylcysteine in the others. All studies reported that symptoms decreased
after treatment with
D-mannose. Despite the limitations of the studies, the consistent results observed among all studies give support to the general findings that
D-mannose may be useful in the treatment of UTI/
cystitis symptoms.