RECURRENCE OF CALCULI IN THE UPPER URINARY-TRACT AFTER PERCUTANEOUS NEPHROURETEROLITHOTOMY

The recurrence of calculi after percutaneous nephroureterolithotomy (PNL) was investigated in 231 cases treated in our clinic between September 1981 and September 1988 and followed up for more than 6 months. The recurrence rate after 3 years for all cases, renal calculi, and ureteral calculi was 17.3%, 20.0%, and 12.7%, respectively. The composition of the calculi was examined in all cases. One patient with uric acid calculi who had discontinued outpatient visits and was not taking prophylactic medication showed postoperative recurrence. Another patient suffering from infectious calculi with many residual stones also showed recurrent growth in the postoperative period. There was no significant difference in the recurrence rate between patients treated with a lithotripter and those treated with forceps. Overall, no significant difference in recurrence rate was observed between patients with and those without residual calculi. However, complete removal of staghorn calculi appeared to reduce the risk of recurrence. The recurrence rate in patients treated by PNL was thought to be comparable to that of patients treated by open surgery.