Unusual cause of renal stone following robotic pyeloplasty.

Non-absorbable Hem-o-Lok clips are commonly used for vascular pedicle control or suture stabilisation during laparoscopic or robotic reconstructive procedures. As they are placed close to suture line and with tension, these clips have a propensity to migrate. We report a case of a 22-year-old man with history of bilateral robotic pyeloplasty presenting with left inferior calyceal stone. He underwent left mini percutaneous nephrolithotomy which revealed an encrusted migrated Hem-o-Lok clip that was used to close the mesenteric window formed during transmesocolic pyeloplasty. Thus, these clips should be used sparingly and only at places where other effective alternatives are unavailable. 2017 BMJ Publishing Group Ltd.