How to Increase the Lithoprotective and/or Litholytic Properties of Urine

Abstract

Recently, several investigators reported that stone patients have a reduced urinary citrate^1,2,3. This citrate “deficit” in stone formers may be the cause of their recurrent calcium calculi. Bach et al.¹ alluded to the low citrate level and the high calcium concentration in the urine of their stone patients. A high Ca/ citrate ratio can be considered as a stone risk factor. The authors emphasized the importance of substances, stimulating the renal citrate secretion, for the prophylaxis of urolithiasis. In accordance with other investigators, the highly significant citrate “deficit” in patients was one of the most pronounced differences between recurrent stone formers and healthy controls that we could find during our six week follow up of the urinary parameters like total and ionized Ca, Mg, Na, Zn. uric acid, creatinine. Pi, urea, citrate, titratable acidity, NH₄ ¹, Ca- and uric acid- crystalluria, surface tension and microerythruria. We however suggest that stone formers are characterized not only by a reduced citrate secretion but also by a general deficit in urinary organic acids, citrate being one of the main representatives.