Ureteropelvic junction obstruction after percutaneous nephrolithotripsy.

Percutaneous nephrolithotripsy is reported to have few complications. However, we have treated 6 cases of complete ureteropelvic junction obstruction that occurred at a number of centers after percutaneous nephrolithotripsy. In 2 patients stones were impacted at the ureteropelvic junction, 3 had pre-existing stenosis and 1 had had no previous structural abnormality. All stones were less than 2 cm. in size and 5 were removed by ultrasonic disintegration. A nephrostogram after percutaneous nephrolithotripsy showed complete ureteropelvic junction obstruction in 4 cases and partial obstruction that progressed to total obstruction in 6 days in 1. In 1 case the nephrostogram was normal but occlusion was noted 2 weeks later. Initial management consisted of nephrostomy drainage for an average of 3.2 months. One patient was treated successfully with a ureteral stent for 6 weeks after balloon dilation, 1 had unsuccessful balloon dilation and 1 had undergone an unsuccessful endoscopic pyelolysis. Pyeloplasty was successful in 3 cases. In 1 patient 2 attempts at pyeloplasty failed and nephrectomy was performed. In the remaining patient ureterocalycostomy failed and interposition of a small segment of ileum was done. Pre-existing stenosis of the ureteropelvic junction or a stone impacted at the junction probably contributed to the obstruction and stenosis in 5 patients. The passage of ureteral guide wires should be avoided in these patients and impacted stones should be dislodged before endoscopic removal. Extracorporeal shock wave lithotripsy is an option in these cases if the stone can be dislodged or bypassed with a stent. Patients with pre-existing ureteropelvic junction obstruction might be treated best by open nephrolithotomy and pyeloplasty or by percutaneous nephrolithotripsy and endoscopic pyelolysis for ureteropelvic junction narrowing.