Study on the correlation between urinary crystals and components of urinary calculi
10.3760/cma.j.cn112330-20250603-00231
- VernacularTitle:尿结晶与泌尿系结石成分的相关性研究
- Author:
Jinan GUO
1
;
Zhongqing MIAO
;
Kefeng XIAO
;
Hongtao JIANG
Author Information
1. 深圳市人民医院（南方科技大学第一附属医院，暨南大学第二临床医学院）泌尿外科，深圳 518020
- Publication Type:Journal Article
- Keywords:
Urinary calculi;
Urinary crystal;
Etiology
- From:
Chinese Journal of Urology
2025;46(10):734-738
- CountryChina
- Language:Chinese
-
Abstract:
Objectives:This study aims to investigate the correlation between urinary crystals and the components of urinary calculi in patients with urinary calculi，as well as the accuracy of urine crystals in predicting stone components.Methods:A retrospective analysis was performed on 280 patients with positive urine crystal and urinary calculi from January 2022 to December 2024. There were a total of 280 patients consisting of 185 males and 95 females，aged from 23 to 80 years，with an average age of（49.1 ± 12.3）years. Among them，there were 243 cases of renal stones or both renal and ureteral stones，25 cases of ureteral stones，and 12 cases of bladder stones. In all cases，10 ml of morning urine was collected preoperatively and sent for examination within one hour. After centrifuging at 400 g for 1 minute，the urine sediment was examined under a microscope. All positive crystals were categorized into calcium oxalate，uric acid，calcium phosphate，magnesium ammonium phosphate，and cystine based on the morphology of the crystals. Calculi were collected after endoscopic surgery，calculi composition was analyzed using infrared spectroscopy，and the main component（the first predominant component）was recorded. Statistical analysis was conducted using a 5×5 contingency table to analyze the correlation and contingency coefficient，and the positive predictive values of the urinary crystals for predicting calculi components were calculated. Results:Among the 280 patients，calcium oxalate crystals were found in 241 cases，uric acid in 25 cases，calcium phosphate in 7 cases，magnesium ammonium phosphate in 5 cases，and cystine in 2 cases. The main components of 280 calculi were calcium oxalate in 232 cases，uric acid in 21 cases，calcium phosphate in 24 cases，magnesium ammonium phosphate in 1 case，and cystine in 2 cases. There was a statistically significant correlation between urinary crystals and stone components（ χ2 = 152.46， P < 0.01），and the contingency coefficient between crystals and calculi components was 0.809. The overall positive expected value of urine crystals was 87.5%（245/280），among which the positive expected value of calcium oxalate crystals was 91.7%（221/241），uric acid crystals was 72.0%（18/25），calcium phosphate was 42.9%（3/7），magnesium ammonium phosphate was 20.0%（1/5），and cystine was 100.0%（2/2）. Conclusions:The urinary crystals of patients with calculi are significantly related to the main components of the calculi. Using urinary crystals to predict the components of the calculi has a relatively high accuracy.
