To analyze the preventive effect of potassium citrate sustained-release tablets on stent mural calculi after ureteral lithotripsy for upper urinary tract calculi and influence on urinary calcium ion and urinary oxalic acid concentration.

The patients with upper urinary tract calculi who underwent ureteral lithotripsy were randomly divided into control group and treatment group. Both groups of patients received routine dietary guidance and health education after surgery. The control group received routine anti-infection, pain relief and stone removal treatment after surgery, while the treatment group received oral potassium citrate sustained-release tablets on the basis of the control group after surgery (1.08 g per time, 3 times a day) continuously until the ureteral stent tube was removed. The ureteral stent tube was removed at 4 or 8 weeks after surgery based on the patient’s recovery status, and the occurrence of stent mural calculi was observed, and 24-hour urine samples were collected from patients during follow-up at 4 weeks after surgery to detect urine pH, levels of uric acid, oxalic acid and citric acid and concentrations of calcium and phosphorus ions. The differences in occurrence of ureteral stent calculi and urine detection indicators were compared between the two groups.

In treatment group, 42 cases were enrolled but 2 cases were lost to follow-up, and 40 cases were finally included for statistical analysis. In control group, 43 patients were included but 3 patients were lost to follow-up, thus 40 patients were enrolled for statistical analysis. Ureteral stents were removed at 4 weeks or 8 weeks after surgery in both groups. The treatment group had a total of 64 ureteral stent tubes retained, and the incidence rate of stent mural calculi was 1.56% (1 case/64 cases). The control group had a total of 62 ureteral stent tubes retained, and the incidence rate of stent mural calculi was 11.29% (7 cases/62 cases, P<0.05). At 4 weeks after surgery, the calcium ion concentrations in treatment group and control group were (2.63±0.66) and (3.45±1.02) mmol·L^-1, oxalic acid levels were (0.41±0.04) and (0.52±0.07) mmol·L^-1, phosphorus ion concentrations were (12.36±2.38) and (16.01±2.16) mmol·L^-1, uric acid levels were (2.02±0.17) and (2.43±0.23) mmol·L^-1, urine pH values were 6.85±0.34 and 6.24±0.34, urine citric acid levels were (1.61±0.22) and (1.39±0.17) mmol·L^-1, respectively (all P<0.05). The adverse drug reactions in treatment group during medication included nausea and diarrhea, with a total incidence rate of 10.00% (4 cases/40 cases). No adverse drug reactions were observed in the control group.

Potassium citrate sustained-release tablets can reduce the incidence rate of stent mural calculi after ureteral lithotripsy for upper urinary tract calculi, and lower the concentrations of urinary calcium ion and oxalic acid.