title: Assay of urinary oxalate: six methodologies compared.
abstract: To assess how well results by different methods for urinary oxalate determinations agree with each other in a clinical setting, we compared six different assays: Hodgkinson and Williams (Clin Chim Acta 36:127-132, 1972), enzymatic, modified Hodgkinson and Williams, gas chromatography, ion chromatography, and "high-pressure" liquid chromatography. For the entire group of samples, the mean value by each method agreed relatively closely, although the enzymatic procedure produced a somewhat higher value. All six methods had large coefficients of variation within (8-58%) and between (15-88%) assays. In addition, analytical recovery by most assays was more than 100% of the added oxalate. Analytical recovery of 10 micrograms of oxalate added per milliliter of urine specimen ranged from 86 to 237%; for 20 micrograms/mL it was 83 to 320%. Thus for the six methods evaluated, no single method appeared to be superior to the others.
mesh_terms: D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D003124:Colorimetry; D006801:Humans; D008722:Methods; D010070:Oxalates / Q000652:urine*; D013223:Statistics as Topic
chemical_list: D010070:Oxalates