A comparative analysis of metabolic and urinary bacterial culture profiles between patients with staghorn and non-staghorn infectious renal stones

OBJECTIVE: To investigate the risk factors of staghorn calculus and explore the differences in the distribution of culturable urine bacteria among patients with infectious renal stones. METHODS: A retrospective analysis was conducted on the clinical data of 201 patients hospitalized in our center from January 2020 to December 2024. Patients who underwent upper urinary tract stone surgery and whose postoperative stone composition analysis indicated that the main component was infectious stones were included. The patients were divided into two groups based on the presence or absence of staghorn calculi. General data, serum biochemical parameters, 24-hour urine metabolic parameters, and urine culture results were collected and compared between the two groups. Univariate and multivariate logistic regression analyses were conducted to identify independent risk factors for staghorn calculus. RESULTS: The two groups revealed no significant differences in terms of gender, age, or comorbidities. Serum calcium levels (P < 0.05), estimated glomerular filtration rate (eGFR) (P < 0.05), and 24-hour urinary calcium levels (P = 0.003) were significantly higher in the non-staghorn stone group than in the staghorn stone group. Multivariate logistic regression analysis indicated that lower serum calcium levels were independently associated with staghorn calculus formation (P = 0.025, OR 0.032, 95% CI [0.002, 0.649]). Urine culture analysis revealed that the detection rate of Proteus mirabilis was significantly higher in the staghorn stone group than in the non-staghorn stone group (31.5% vs. 2.4%, P = 0.001). CONCLUSION: This study suggests that lower serum calcium levels and Proteus mirabilis infection are associated with staghorn calculi in patients with infectious stones. Clinically, monitoring serum calcium levels and managing urinary tract infections may help reduce the risk of staghorn calculus progression and preserve renal function. However, these findings require further validation through prospective studies.