Cranberry-lingonberry juice affects the gut and urinary microbiome in children - a randomized controlled trial

Area of Science:

• Microbiology
• Pediatrics
• Nutrition Science

Background:

• Urinary tract infections (UTIs) are common in children, and the preventive mechanisms of cranberry-lingonberry juice (CLJ) are not well understood.
• Previous research suggests CLJ may prevent UTIs, but the underlying biological mechanisms, particularly effects on the microbiome, require further investigation.

Purpose of the Study:

• To investigate the impact of CLJ consumption on the urinary and gut microbiome composition in children diagnosed with UTIs.
• To determine if CLJ alters the abundance of specific bacterial taxa or overall microbial diversity in the urinary and gut tracts.

Main Methods:

• A randomized controlled trial involving 113 children with UTIs, allocated to consume either CLJ or a placebo juice for six months.
• Collection of urinary samples at three months and fecal samples at three, six, and twelve months.
• Next-generation sequencing of the bacterial 16S gene was employed to analyze microbiome composition and diversity.

Main Results:

• Children consuming CLJ showed a decreased abundance of Proteobacteria (p=0.03) and an increased abundance of the Firmicutes phylum (p=0.04) in their urinary microbiome at three months.
• While Escherichia coli abundance was lower in the CLJ group (6%) compared to placebo (13%), this difference was not statistically significant (p=0.42).
• The gut microbiome in children receiving CLJ exhibited a higher abundance of Actinobacteria at three and twelve months. No significant differences in overall urinary or gut microbiome diversity were observed between the groups.

Conclusions:

• Cranberry-lingonberry juice consumption significantly alters the urinary microbiome composition in children with UTIs, specifically by reducing Proteobacteria and increasing Firmicutes.
• The study provides evidence that CLJ modifies both urinary and gut microbiomes, suggesting a potential mechanism for UTI prevention.
• Maintaining a healthy urinary microbiome may be a critical factor in preventing recurrent UTIs in pediatric populations.