Long-Term Comparison of Renal Function in Patients with Solitary Kidneys and/or Moderate Renal Insufficiency Undergoing Extracorporeal Shock Wave Lithotripsy or Percutaneous Nephrolithotomy

Abstract

We compared the long-term effects of extracorporeal shock wave lithotripsy (ESWL††Dornier Medical Systems, Inc., Marietta, Georgia.) and percutaneous nephrolithotomy monotherapy on renal function in 31 patients with a solitary kidney and/or chronic renal insufficiency who were all more than 2 years after treatment (mean 41.5 months). The change in the reciprocal of serum creatinine was used as an index to estimate changes in the glomerular filtration rate. A change of 20% or greater in the glomerular filtration rate was considered a clinically significant deterioration of renal function. The rate of deterioration of renal function in patients with a solitary kidney and creatinine of less than 2mg./dl. was 22% for ESWL and 29% for percutaneous nephrolithotomy, respectively. All patients with a creatinine between 2 and 3mg./dl. demonstrated long-term improvement of renal function regardless of the treatment modality. All 4 patients with creatinine greater than 3mg./dl. undergoing ESWL had short-term improvement but eventual long-term deterioration of renal function. Indeed, 3 of these patients required dialysis within 2 years from the treatment dates. One patient with creatinine greater than 3mg./dl. who underwent percutaneous nephrolithotomy demonstrated stabilization of the renal function after treatment. From our data, no convincing evidence could be found to suggest that ESWL results in long-term deterioration of renal function in patients with chronic renal insufficiency or a solitary kidney. We conclude that the choice between ESWL and percutaneous nephrolithotomy should be based on the stone composition, stone location and stone burden, rather than on the preexisting renal function or presence of a solitary kidney.