LAUSR

Background Hem-o-Lok clips (HOLCs) are widely used in minimal access urological operations due to the advantage of vascular control and suture stabilization. In rare cases, however, they can develop problems themselves. Migration of HOLCs into the collecting system is a fairly rare complication after laparoscopic pyelolithotomy. To date, only two cases were reported in the literature. Case presentation This article describes a case of 51-year-old man with a complaint of left flank pain. He had a medical history of ipsilateral retroperitoneal laparoscopic pyelolithotomy at another hospital 8 years ago. Non-contrast CT scan demonstrated a renal stone in the left ureteropelvic junction complicated by mild hydronephrosis. A straight foreign body was found near the renal pelvis, with part of it wedging into renal pelvic wall. A percutaneous nephrolithotomy (PNL) was performed for this patient. After some fragmentation, a HOLC was found in the kernel of the stone. With an alligator plier, the clip was totally removed out of the collecting system. The postoperative period and follow-up were uneventful. Conclusions HOLC migration into renal pelvis is a rare complication following laparoscopic pyelolithotomy. It could act as nidus for stone formation under extended exposure to urine. Using HOLCs to stabilize the anastomotic suture near renal pelvis should be avoided to prevent this complication. Instead, knotting is a better choice under such condition. The secondary calculi and dislodged HOLCs can be removed through PNL by an alligator plier after laser lithotripsy.