Urine oxalate levels in a New Zealand reference population and renal stone formers

Increasing attention is being given to oxalate as a risk factor in urinary calcium stone disease. The accuracy of some methods for measuring urine oxalate is uncertain. Using gas chromatography urine oxalate levels were 0.36 +/- 0.02 and 0.31 +/- 0.02 (mmol/24 h +/- 1 SEM) for men and women respectively of a reference population. In recurrent stone formers urinary oxalate was 0.43 +/- 0.03 in males and 0.38 +/- 0.04 for females whilst solitary stone forming females excreted only 0.31 +/- 0.04 mmol/24 h. The difference between males and females of the reference population was significant (p less than 0.05) as was the difference between reference males and male stone formers.