Percutaneous nephrolithotomy in renal transplants: a safe approach with a high stone-free rate.

Objectives: The purpose of this report is to assess the safety and efficacy of percutaneous nephrolithotomies (PNL) in transplanted kidneys.

Methods: Patient characteristics, predisposing factors, clinical presentation, surgical details, complications and outcomes were analyzed.

Results: Between April 2002 and August 2009, seven patients (average 44 years old, 4 women and 3 men) were treated. Predisposing factors included hyperuricemia, hyperparathyroidism, recurrent urinary tract infection (n = 2 each) and retained double-J ureteral stent (n = 1). Clinical presentation consisted of urinary tract infection alone (n = 3) or in association with impaired renal function (n = 2) but also hematuria (n = 1) or impaired renal function (n = 1). Patients were treated in supine position, and calyx puncture was guided by the combination of ultrasound and fluoroscopy. Combined ultrasound and pneumatic lithotripsy (n = 5) or extraction (n = 2) was performed. Overall average stone size was 32.8 mm (range 20-50). Mean operative time was 102 min (range 75-150). Stone-free status was achieved in 6 patients (85.7%). No intraoperative complications occurred, including major bleeding. Mean initial and postoperative serum creatinine levels were 2.04 and 1.59, respectively. Average admission time was 6.9 days (range 4-9).

Conclusions: PNL of transplanted kidneys is a safe and effective method associated with a high overall stone-free rate. This approach should be considered in centers where expertise is available.