Treatment of lithiasis in patients with one kidney by extracorporeal shock wave lithotripsy

OBJECTIVE: To describe the efficacy of extracorporeal shock wave lithotripsy in the treatment of lithiasis in patients with solitary functioning kidney. METHODS: The study comprised 56 patients with solitary kidney that had been treated by extracorporeal shock wave lithotripsy. These patients had a solitary kidney for the following reasons: 30 had undergone nephrectomy due to lithiasis, 11 had lost renal function arising from lithiasis, 9 had undergone nephrectomy for other pathologies and 6 had renal agenesis. Nine stone variables and treatment were analyzed. The same variables were analyzed and compared for statistical significance in a representative sample of 125 lithiasic patients with two kidneys who were treated by ESWL. RESULTS: Patients with solitary kidney frequently had a single calculus of < or = 1 cm located in calyces, unobstructive and did not require complementary endourological procedures. The mean number of shock waves was 8535. The psot-lithotripsy success rate was 82.1%; 98.2% had no complications. Comparison of these variables in both groups of patients showed statistically significant differences for stone location, indication for complementary endourological procedures and the number of shock waves utilized. CONCLUSIONS: In our view, ESWL is the treatment of choice in patients with lithiasis in a solitary kidney due to its high success rate and low morbidity. Stringent criteria must be employed before indicating prior endourological procedures to preserve the patency of the excretory tract and to minimize the risk of ureteral obstruction.