ESWL monotherapy for large-volume renal calculi: efficacy and morbidity

We assessed the efficacy and morbidity of extracorporeal shock-wave lithotripsy (ESWL) monotherapy in the treatment of 25 consecutive patients with large-volume renal calculi (surface area greater than or equal to 5.0 cm2). Eighteen of the calculi were infection (struvite) stones and 7 were sterile stones. In 21 cases internal ureteral stents were positioned before ESWL, but no patient underwent pretreatment percutaneous nephrostomy (PCN) or percutaneous nephrostolithotomy (PNL). An average of 2.1 procedures including ESWL, PCN, or ureteral interventions were required to achieve a stone-free renal collecting system and ureter, or residual stone particles less than 4 mm in diameter confined to the renal collecting system. Sixty percent of the patients required no ancillary procedures after ESWL. There were no differences in the mean duration of hospitalization, need for post-treatment ancillary procedures, time to clearance of ureteral fragments, and incidence of residual stone particles among patients with infection and sterile stones. Of 23 patients observed greater than three months (mean 10.9 mos) after ESWL, 43 percent had residual stone particles in the renal collecting system. Expansion of these particles or stone recurrence in the absence of residual particles has not been observed. We conclude that large volume renal calculi may be managed effectively and safely with ESWL monotherapy.