Management of a patient with a double J stent knotted at the
Ureteral double J stents are widely used in urologic procedures to relieve an obstruction or as an adjunct to other treatments. Ureteral stents are safe, and because of their widespread usage, complications associated with stenting increased. The knotting of the ureteral stent is an uncommon complication.

A 25-years old female patient presented with complaints of bilateral flank pain. The physical examination and laboratory findings were unremarkable except for microscopic hematuria. The computerized tomography (CT) revealed a left-sided 15 mm and a right-sided 13 mm renal pelvis stone with marked dilatation in both collecting systems, more prominent in the left kidney. Retrograde intrarenal surgery (RIRS) with laser lithotripsy was performed in the left kidney, and a 4,8F double J ureteral stent was inserted to the right side with a stone-free left kidney. Three weeks after discharge, the patient was re-admitted for a second RIRS to the right kidney, and stent was introduced. This procedure was uneventful, and the patient was discharged the day after surgery. The patient presented to the clinic ten days postoperatively with the complaint of increasing right flank pain.

A plain kidney-ureter-bladder (KUB) X-ray showed a downward migrated ureteral stent. She was taken to the operating room for stent removal. Cystoscopy was performed, and the migrated stent was gently pulled by grasping forceps under fluoroscopic guidance. However, this maneuver failed, so surgeons advanced the ureteroscope until they detected a knot formation in the mid-portion of the stent at the level of the distal ureter. Although they reached the knot and noticed that the guidewire passed beyond the knot, the ureteroscope could not pass it. They pulled the ureteroscope and the guidewire out following this maneuver and attempted to remove the stent again by grasping forceps. They could successfully remove the knotted stent probably with the help of the dilating effect of the guidewire and particularly the 7F ureteroscope. They inserted a 5F ureteric catheter and a 16F Foley catheter; and removed one-day letter successfully.