Ureteroscopic management of recurrent renal cystine calculi

Background and Purpose: Patients with recurrent cystine nephrolithiasis oft entimes require multiple procedures for stone removal. As the majority of c ystine stones are resistant to the effects of shockwave lithotripsy, repeat percutaneous surgery is often required and may cause renal damage. Moreove r, repeat percutaneous access may become more difficult as perinephric fibr osis develops. Small-caliber ureteroscopes along with the holmium laser now enable routine intrarenal ureteroscopic access to symptomatic renal stones . Herein, we present our experience in managing recurrent renal cystine cal culi using flexible ureterorenoscopy and assess whether such an approach ma y be used as an alternative to percutaneous surgery in selected patients. Patients and Methods: Three patients with large-volume (mean diameter 22 mm ) renal cystine stones were managed with a 7.5F flexible ureterorenoscope c ombined with holmium laser lithotripsy to fragment the stones completely. Results: The mean treatment time was 97 minutes, with successful fragmentat ion in all cases. Two of the three patients were completely stone free on f ollow-up intravenous urography, with the third patient having only small-vo lume residual fragments in a lower pole calix, All patients are currently a symptomatic and are being maintained on high oral fluid intake, urinary alk alization with potassium citrate, and alpha-mercaptopropionylglycine to red uce urinary cystine excretion. Conclusion: Flexible ureterorenoscopy with holmium laser lithotripsy provid es a reasonable alternative for the management for recurrent cystine calcul i in patients who are not candidates for repeat percutaneous procedures. Al though it is time consuming, complete stone fragmentation, along with clear ance of fragments, can be achieved in the majority of patients.