Endoscopic management of retained renal foreign bodies

To review our experience with endoscopic extraction of renal foreign bodies. We assessed the preoperative factors associated with renal failure, operative planning and technique, and postoperative outcomes. Retained foreign bodies in the kidney from previous endoscopic and/or percutaneous manipulation can be technically challenging.

We retrospectively reviewed our database from November 1992 through April 2008 for patients who had undergone extraction of a renal foreign body.

A total of 21 patients were identified who met the selection criteria (11 men and 10 women), with a mean age of 41 +/- 22 years. The renal foreign bodies included indwelling ureteral stents (n = 15), nephrostomy tubes (n = 3), the inner core of a guidewire (n = 1), a nephrostomy tube pull string (n = 1), and a laser fiber (n = 1). Of the 21 patients, 15 (71%) required antegrade instrumentation by way of a percutaneous tract to remove the foreign body. Extraction of the nephrostomy pull string, fragmented guidewire, and laser fiber remnant were approached percutaneously. In the case of a retained ureteral stent, all but 2 required a combined antegrade and retrograde approach for extraction. Patients presenting with renal insufficiency (n = 5), defined by a creatinine >1.5 mg/dL, had obstruction resulting from a forgotten ureteral stent that had been left in place for among the longest periods in our cohort (range 1.5-10 years). Two fifths of these patients had improvement in renal function after endoscopic extraction.

Patients with retained renal foreign bodies benefit from extraction by way of retrograde and/or antegrade endoscopic techniques. In patients presenting with renal failure, improvement in renal function is often seen after extraction of a retained renal foreign body.