The roles of bacteria on urolithiasis progression and associated compounds.

As a common urological disease, the formation of urinary tract stones involves multiple factors, including genetics, the environment, dietary habits, and bacterial species (e.g., Proteus mirabilis and Escherichia coli). Previous studies have demonstrated that P. mirabilis primarily contributes to infectious urinary calculus formation by producing urease, an enzyme that breaks down urea into ammonia and carbon dioxide, thereby altering the urinary pH and promoting crystal formation and growth. In contrast, calcium oxalate (CaOx) stones are the main type of kidney stones, and the most common bacteria in CaOx stones are E. coli. Intriguingly, E. coli can also facilitate stone formation via flagellin and other virulence factors, which induce renal epithelial cell injury and increase crystal adhesion and aggregation. These bacteria play complex and multidimensional roles in the formation of urinary tract stones, necessitating further research to elucidate their underlying mechanisms. Here, we summarise the roles of common urinary tract bacteria, particularly P. mirabilis and E. coli, in forming urinary tract stones, aiming to enhance our understanding of urolithiasis exploration in the future.