Relationship between the severity of renal stone disease and urine composition

The biochemical findings in urine from 62 male and 20 female consecutive patients with renal stone disease were studied in relation to the size of concrements and the estimated rate of stone formation. There appeared to be good agreement between urine composition and stone history. Biochemical grouping of the patients resulted in different distributions in the different groups of stone-formers. The quotients calcium/magnesium (k1) and calcium X oxalate/magnesium X creatinine (k3) appeared to reflect the severity of stone disease and seemed to provide a rational approach to the evaluation of patients with urolithiasis.