The efficacy of medical prophylaxis in children with calcium oxalate urolithiasis after percutaneous nephrolithotomy.

To evaluate whether medical prophylaxis decreases calcium oxalate stone recurrences in children after percutaneous nephrolithotomy (PNL) or not. To our knowledge this is the first study that evaluates this topic in children after PNL. We researched analysis of 42 children with calcium oxalate stone disease. They were divided into two groups. Twenty-two children who had a follow-up with medical prophylaxis after PNL were included in group I; 20 children who did not have medical prophylaxis were included in group II. They were all stone free and they were evaluated with 24-hour urine analysis and blood samples, abdominal X-ray, and ultrasonography. The average follow-up was 25.9 (12-42) months for group I and 24.6 (14-40) months for group II. Age, gender, follow-up time, and 24-hour urine samples were similar between groups (p>0.05). New stone formation was detected in two (9.1%) and seven (35%) patients in group I and II, respectively. New stone formation seemed to be higher in group II, but because of the less number of patients, this difference was not statistically significant (p=0.062). The number of patients with recurrence was statistically higher in group II (p=0.032). Stone formation rate (SFR) was calculated as 0.034 and 0.2 per patient per year for group I and II, respectively. This difference of SFR between groups was statistically significant (p=0.028). Medical prophylaxis of children after PNL can reduce new stone formation and SFR. Although it was not statistically significant because of low patient numbers, higher recurrence rate was detected in patients who did not have medical prophylaxis.