Epidemiological and clinical characteristics of stone composition: a single-center retrospective study

The aim of the study was to investigate the epidemiological characteristics of stone components in patients with urolithiasis and analyze the associations between stone components with patients' clinical characteristics. A total of 7126 patients with urolithiasis between July 2005 and June 2020 were retrospectively analyzed. In this research, calcium oxalate stones (74.6%) accounted for the highest proportion, followed by infection stones (11.8%), uric acid (10.6%), brushite (2.0%), and others (1.1%). The change in trend in the composition of urinary stones revealed that the proportion of uric acid declined steadily, while the content of infection stones increased gradually over 15 years. The results also suggested that stone composition was significantly associated with PM2.5, gender, age, BMI, diabetes, hypertension, CCVD, alcohol consumption, albumin, creatinine, WBCHP, leukocyte, urine pH, nitrite and urine culture (P < 0.05). However, there was no significant correlation between stone composition with smoking, WBC and NEU% (P > 0.05). Our study concluded that calcium oxalate represented the highest proportion, followed by infection stones, uric acid, brushite, and others. The proportion of uric acid declined steadily, while the infection stones increased gradually. Furthermore, the factors influencing the formation of urinary calculi are PM2.5, gender, age, BMI, diabetes, hypertension, CCVD, alcohol consumption, albumin, creatinine, WBCHP, leukocyte, urine pH, nitrite and urine culture. Collectively, these results may provide clues to establish effective prevention and management strategies for urinary calculi.