Calculation of Complex Chemical Equilibria in Urine: Estimation of the Risk of Stone Formation and Derivation of Prophylactic Measures

  • W. Achilles
  • B. Ulshöfer


The degree of supersaturation of a precipitating system is defined as G = -RT ln(AP/Ksp), where AT = the activity product of the precipitating ions and Ksp= the corresponding solubility product. In solutions such as urine containing interacting ligands and metal ions, the AP may be governed by multiple equilibrium reactions. This is the case with calcium oxalate, one of the most important constituents of urinary stones. From the corresponding thermodynamic equilibrium constants, AP can be calculated from the total concentrations of all the ions concerned and the pH of the solution1-4.


Stone Formation Calcium Oxalate Urinary Stone Urinary Oxalate Calcium Oxalate Stone 
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Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • W. Achilles
    • 1
  • B. Ulshöfer
    • 1
  1. 1.Urologische Universitätsklinik und Poliklinik MarburgMarburgGermany

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