Endoscopic Combined Intrarenal Surgery for Stone Formation After Previous Laparoscopic and Open Renal Surgery.

Nonabsorbable sutures used during renal surgery represent a known substratum for stone growth. We hereby describe two cases of nephrolithiasis secondary to permanent suture material, originally placed during conservative renal surgical procedures and afterward migrated into the caliceal system, managed with endoscopic combined intrarenal surgery (ECIRS) with subsequent complete renal clearance. . A 54-year-old male, with history of laparoscopic excision of a left parapelvic cyst, presenting with left inferior caliceal stone. . A 79-year-old female, who underwent open enucleation of a left renal pelvis tumor 15 years before. She presented with bilateral lithiasis, including a staghorn stone in the left renal pelvis. Both patients underwent left ECIRS by two surgeons, revealing the presence of suture devices, which were completely removed. Abdominal CT at 1 month after surgery did not show residual lithiasic fragments in both cases. To prevent the risk of stone formation, it is mandatory to use nonabsorbable suture agents sparingly during conservative renal surgery and furthermore to remove all foreign material from the collecting system because they have the potential for calculi growth. In this sense, ECIRS technique may also avoid further open or minimally invasive surgery and the use of suture instruments.