Urinary microbiota in patients with kidney stones: a systematic review and meta-analysis

The global prevalence of kidney stones (KS) has been on the rise in recent years. Numerous studies have suggested an association between urine microbes and KS, although the precise underlying mechanisms remain unclear. This meta-analysis and systematic review aim to investigate the urine microbiota composition in patients with KS and delineate the disparities in urine microbiota between healthy individuals and KS patients.

A systematic search was conducted on PubMed, Embase, and Web of Science databases to identify relevant studies. Seven studies were selected for analysis to compare the urinary microbiota profiles of KS patients with controls. This research adhered to the PRISMA guidelines, with data extraction performed independently by two researchers. The study outcomes focused on assessing differences in the α-diversity index of urinary microbiota between KS patients and healthy controls, as well as discrepancies in microbiota abundance at the phylum, genus, and species levels. Statistical analyses were carried out using Review Manager 5.4.1 and Stata 17.0 software. The I² statistic was utilized to evaluate result heterogeneity, and a sensitivity analysis was conducted to explore potential sources of heterogeneity. Publication bias was assessed through funnel plots and Egger's tests. This study is registered with PROSPERO (No. CRD42024506599).

We have searched PubMed, Embase and Web of Science and analyzed statistics by using Review Manager 5.4.1 and Stata 17.0 software. Our research has included seven articles with a total of 162 kidney stone patients and 139 healthy controls. Based on our results, compared to healthy controls, the α-diversity of KS patients including Shannon index is significantly lower (SMD -0.55, 95 % CI, -1.10∼ -0.01). However, the relative abundances of Acinetobacter, Pseudomonadota and Corynebacterium of patients are higher than healthy controls, while the abundances of Bacilliota and Bacteroides are lower.

The meta-analysis and systematic review has indicated that the urinary microbiota is not only different between patients with KS and healthy people, but also relates to the pathogenesis of kidney stones. The results suggests that diet modification or appropriate use of antibiotics may effectively prevent the development of KS.