To study the constituents of urinary stones in patients in Zhejiang, and analyze the composition difference between patients from northern Zhejiang province and southern Zhejiang province.

From October 2012 to October 2018, clinical data of 4 423 urinary stone patients treated in Sir Run Run Shaw Hospital, the Second Affiliated Hospital of Wenzhou Medical University, and Huzhou First People's Hospital was retrospectively analyzed. Infrared spectrum was used to analyze urinary calculi constituents. Among 4 423 patients, there were 3 041 males and 1 382 females, male to female ratio was 2.2∶1, and the mean age was (51.2±16.5) years. There were 2 974 northern Zhejiang patients and 1 449 southern Zhejiang patients. High incidence age group was 41- 60 years[48.2%(2 136/4 423)]. The distribution characteristics of urinary calculi constituents in different groups of sex, age, and region were analyzed.

Among the 4 423 cases, the mixed urinary stones were dominant in the urinary calculus [73.1%(3 235/4 423)], in which, the most component was the calcium oxalate monohydrate+ calcium oxalate dehydrate+ carbonated apatite [36.2%(1 604/4 423)]; among the pure stones, the most component was the calcium oxalate monohydrate[16.3%(719/4 423)]. Carbonated apatite stones [70.1%(970/1 382) vs. 61.0%(1 856/3 041), P<0.05]and magnesium ammonium phosphate stones [12.7%(176/1 382) vs. 4.9%(150/3 041), P<0.05]were both more prevalent in females than males, but uric acid stones[10.6%(325/3 041) vs. 5.8%(81/1 382), P<0.05] were more common in males than females. The proportions of calcium oxalate stones[90.6% (961/1 060) vs. 76.2%(935/1 227), P<0.05], carbonated apatite stones[77.6%(823/1 060) vs. 50.7%(623/1 227), P<0.05], and magnesium ammonium phosphate stones[9.1%(97/1 060) vs. 6.5%(80/1 227), P<0.05] of 0-40 years group were all higher than >60 years group, however, uric acid stones were more frequent in >60 years group [3.5%(38/1 060) vs. 17.0%(209/1 227), P<0.05]. The proportion of calcium oxalate stones in southern Zhejiang was lower than northern Zhejiang [79.0%(1 145/1 449) vs. 89.4%(2 661/2 974), P<0.05]. However, carbonated apatite stones [71.5%(1 037/1 449) vs. 60.1%(1 789/2 974), P<0.05], magnesium ammonium phosphate stones [15.1%(220/1 449) vs. 3.5%(106/2 974), P<0.05], and uric acid stones [10.7%(156/1 449) vs. 8.4%(250/2 974), P<0.05] were more prevalent in southern Zhejiang than northern Zhejiang.

The distribution of constituents of urinary stones in Zhejiang was different in genders, age, and regions. Carbonated apatite stones and magnesium ammonium phosphate stones were more prevalent in females and young people, and uric acid stones were more common in males and old people. Calcium oxalate stones were more common in youths. Moreover, calcium oxalate stones were more frequent in northern Zhejiang, and carbonated apatite stones, magnesium ammonium phosphate stones and uric acid stones were common in southern Zhejiang.

Urinary calculi; Analysis of constituents; Gender; Age; Region