More than 20 years ago, Boyce (1) and Howard (2) introduced the concepts of matrix theory and inhibitor theory of stone formation, respectively. These theories are still very much in vogue today. The normal urinary environment is typically supersaturated with respect to stoneforming salts. The lack of stone formation in normal subjects must, therefore, reflect the presence of inhibitors or a lack of promoter role of matrix or other substances. Conversely, stone formation in patients with nephrolithiasis might be indicative of a lack of inhibitors or a relative excess of promoters.
KeywordsStone Formation Calcium Oxalate Relative Excess Pentosan Polysulfate Oxalate Dihydrate