RESUMEN
Patients with medullary spongy kidney(MSK) who recurrently form and pass stones are in danger of developing obstructive nephropathy. Since extracorporeal shock wave lithotripsy (ESWL) was introduced to treat urinary tract stones, the shock wave application to MSK with stones has been performed. Between February, 1990 and August, 1992, 11 renal units in 7 patients were diagnosed as stones in MSK on intravenous urography. These patients were all symptomatic with hematuria and/or flank pain, and then treated by ESWL. The number of stone-burden minor calyces was 1 to3 in 2 cases( 18.2%), 4 to 6 in 8 cases ( 72.7% ) and 7 or more in 1 case(9.1%). The average numbers of treatment for these stones were 8.5, 13.4 and 4 sessions, respectively and the average storage was 386, 470 and 115, respectively. Reduction in the number and size of the stones on plain films was more than ?5% in 5 cases( 45.4%), 25 to 75% in 4 cases( 36.4%), and less than 25% in 2 cases( 13.2%). Serum creatinine, blood urea nitrogen, and creatinine clearance rate did not show any change after the treatments. The post-ESWL complication was only persistent gross hematuria for 4 days in 1 case( 14.3% ) In conclusion, although ESWL does not clear the stones completely, the ESWL is considered to be an effective procedure to prevent an obstructive nephropathy and to reduce the frequency of symptomatic stone passage in medullary spongy kidney with stones.