Extracorporeal shock-wave lithotripsy monotherapy of partial staghorn calculi

To define factors affecting the success and long-term outcome of extracorporeal shock-wave lithotripsy (ESWL) monotherapy of partial staghorn calculi.We retrospectively reviewed 92 patients with partial staghorn calculi who were treated with ESWL monotherapy. The outcome of the treatment was evaluated after 3 months. Long-term follow-up data (24 months) were available for 49 patients. These data were further analyzed to determine long-term outcome.At 3 months, the overall stone-free rate was 59.8%. Multiple ESWL sessions were required in 85.8% of patients. Stone surface area500 mm2 was the only factor that significantly decreased the stone-free rate. Post-ESWL complications occurred in 12 patients (13%), among whom renal obstruction was observed in 10.8%. Secondary procedures were needed in 17 cases (18.4%). After a mean follow-up period of 7.5 years, the stone-free rate was 59.2% (29/49) and one-third of patients developed recurrence. In the long term, clinically insignificant residual fragments (CIRFs) passed spontaneously in 23% of patients, remained stable in 38.5% and became bigger in 38.5%. Regrowth of CIRFs was related to a history of stone recurrence. No patients showed deterioration of kidney function on the treated side and an improvement in pre-ESWL hydronephrosis was observed in 73.3% of patients.ESWL is suitable for staghorn stonesor=500 mm2. In the long term, CIRFs became bigger and required secondary intervention in one-third of patients. A history of stone recurrence is a significant predictor of regrowth of CIRFs. ESWL provides long-term preservation of function of the treated kidneys; however, one-third of patients develop recurrence.