Clinical characteristics of surgically managed patients with asymptomatic renal stones: Comparison of patients with symptomatic renal stones

PURPOSE: This study aimed to compare the characteristics of asymptomatic and symptomatic nephrolithiasis in patients who underwent surgical treatment for kidney stones. MATERIALS AND METHODS: Between 2015 and 2019, 245 patients who underwent percutaneous nephrolithotomy or retrograde intrarenal surgery for kidney stones were included. The patients were divided into asymptomatic (n=124) and symptomatic (n=121) groups. All patients underwent blood and urine tests, preoperative non-contrast computed tomography, and postoperative stone composition analysis. We retrospectively analyzed and compared the characteristics of the patients and stones, operation time, stone-free rate, and postoperative complications between the two groups. RESULTS: In the asymptomatic group, mean body mass index (BMI) was significantly higher (25.7±3.8 kg/m(2) vs. 24.3±2.8 kg/m(2), p=0.002) and urine pH was significantly lower (5.6±0.9 vs. 5.9±0.9, p=0.013). The ratio of calcium oxalate dihydrate stones was significantly higher in the symptomatic group (5.3% vs. 15.5%, p=0.023). No significant differences were observed in stone characteristics, postoperative outcomes, or complications. In the multivariate logistic regression analysis for predicting variables for asymptomatic renal stones, BMI (odds ratio [OR], 1.144; 95% confidence interval [CI], 1.038–1.260; p=0.007), and urine pH (OR, 0.608; 95% CI, 0.407–0.910; p=0.016) were independent predictive variables for asymptomatic renal stones. CONCLUSIONS: This study demonstrated that thorough medical check-ups are needed for the early detection of renal stones in individuals with a high BMI or low urine pH.