The efficacy of potassium citrate based medical prophylaxis for preventingupper urinary tract calculi: A midterm followup study

Purpose: We examined the efficacy of potassium citrate based medical prophy laxis for preventing upper urinary calculous recurrence, and compared it wi th the stone recurrence rate in patients who only received intermittent or no medical prophylaxis. Materials and Methods: We retrospectively reviewed the records of 493 patie nts with upper urinary calculi, of whom 237 men and 76 women with a mean ag e of 56.1 and 51.4 years, respectively, were enrolled in the study. Of the 313 participants 64 (group 1, 20.4%) received regular medical prophylaxis f or 24 to 42 months (mean 27.8), 80 (group 2, 25.6%) received intermittent m edical prophylaxis for 1.5 to 19 months (mean 7.9) and 169 (group 3, 54%) d id not receive any medical prophylaxis. Results: At midterm followup of 24 to 60 months 107 patients (34.2%) had st one recurrence. In group 1 the stone recurrence rate was 7.8%, which was si gnificantly less (p <0.001) than in groups 2 (30%) and 3 (46.2%). Similarly new calculous events in patients with a history of multiple stone recurren ce were less frequent in group 3. than in groups 2 and 3 (9.7, 47.4 and 52. 2%, respectively, p <0.001). Multiple stone recurrence history, hypercalciu ria, hyperuricosuria and calcium oxalate dihydrate calculi were independent risk factors for stone recurrence. Conclusions: Regular medical prophylaxis may effectively prevent stone recu rrence regardless of previous treatment modalities, stone composition, meta bolic abnormalities and stone-free status. Cost effectiveness, patient comp liance and gastrointestinal upset may limit patient acceptability and clini cal use of medical prophylaxis. However, patients with a history of multipl e stone recurrence, calcium oxalate dihydrate stones, hypercalciuria and hy peruricosuria benefit from regular medical prophylaxis.