Influence of Ammonium Concentration and Anion Gap on Relative Supersaturations in the Urine of Stone Forming Patients

For the computation of the relative supersaturation (RS) for struvite, the concentration of ammonium must be known. To estimate ammonium concentration, the use of the anion gap has been proposed1. The purpose of this study was to compare the influence of ammonium concentration and anion gap on the RS of struvite, calcium oxalate monohydrate (COM), brushite, and uric acid.