Extracorporeal shock wave lithotripsy for renal stones with renal cysts present.

While reports differ on the effect of extracorporeal shock wave lithotripsy (ESWL*) on renal cysts, little has been written on the stone-free status following ESWL for renal calculi with renal cysts present. We studied 13 patients with renal stones plus renal cysts, and only 6 (46%) were stone-free at 3 months after ESWL. While the number of cases is small, it is believed that renal cysts may interfere with the passage of stone fragments due to the impediment of drainage, and urinary stasis from the stretching and distortion of the caliceal system by the renal cysts.