ACUTE CHANGES IN RENAL-FUNCTION FOLLOWING EXTRACORPOREAL SHOCK-WAVE LITHOTRIPSY IN PATIENTS WITH A SOLITARY FUNCTIONING KIDNEY

Twelve consecutive patients with a solitary functioning kidney were treated for renal stone by extracorporeal shock wave lithotripsy (ESWL*) with the modified Dornier HM3 lithotriptor and studied for 3 days after treatment. Urinary excretion of electrolytes, N-acetyl-beta-glucosaminidase (NAG), alkaline phosphatase, kallikrein, glycosaminoglycans, albumin and beta-2-microglobulin, and clearances of creatinine, inulin and para-aminohippuric acid were determined, as were serum levels of creatinine, urea, beta-2-microglobulin and aldosterone, and plasma renin activity. Urinary flow rate, free water clearance, and urinary excretion of NAG, kallikrein and beta-2-microglobulin were significantly increased 0 to 24 hours after ESWL. The urinary excretions of alkaline phosphatase, albumin and glycosaminoglycans were unchanged. Glomerular filtration rate was significantly decreased and effective renal plasma flow was unchanged. Filtration fraction was stable. Serum lactic dehydrogenase increased significantly after ESWL and remained high through the period of observation. Serum levels of creatinine, beta-2-microglobulin and aldosterone were unaltered. A decrease in plasma renin activity immediately after treatment is explained by the water immersion and the extracellular volume expansion during treatment.