Simplified method for enzymatic urine oxalate assay.

A procedure for the quantitative determination of oxalate in urine suitable for use in clinical laboratories is described. Oxalate is extracted from urine and subsequently assayed by measuring the amount of hydrogen peroxide produced in an oxidation reaction catalyzed by oxalate oxidase. The reproducibility of the method was assessed by within-run and day-to-day reproducibility studies and the accuracy of the method was assessed by determining the amount of oxalate recovered in spiked urine samples. The correlation obtained between the method described here and a reference method was 0.976.