Retrograde transureteral approach: a safe and efficient treatment for recurrent cystine renal stones.

Most patients presenting cystinuria require multiple urological procedures during their lifetime. In this kind of patients the availability of minimally invasive procedure represents an advantage of minimizing the cumulative morbidity of several repeated treatments. Herein we report our experience using ureterorenoscopy (URS) for the treatment of recurrent renal cystine stones. From 2003 to 2007, 10 patients (4 males and 6 females) with one or multiple recurrent renal cystine stones underwent URS. Overall, 21 procedures have been performed. Mean maximum diameter of stones was 11.2 mm (range 5-30 mm). Either 8-9.5 F semirigid or 7.9 F flexible ureteroscopes were used. In 6 cases, stones were removed using a basket; in 9 procedures laser lithotripsy with flexible scope was performed; in 6 cases renal calculi were pulled down in the ureter using flexible instrument and then shattered with laser introduced by semirigid instrument. Stone-free status was defined as the absence of any residual fragment. A complete stone clearance was obtained in 15 out of 21 procedures (71%). In 5 cases (24%) significant residual fragments occurred; in the remaining case (5%) URS was ineffective. In 5 out of these unsuccessful procedures, stone clearance was obtained with auxiliary treatments. The last patient has not been treated yet. No major complications occurred as a result of the procedures. URS offers excellent advantages in case of recurrent hard calculi such as cystine stones. Minimally invasive procedures allow satisfactory outcomes, improving patients' quality of life.