Plasma and urinary oxalate and glycolate in healthy subjects

Abstract

High-performance ion chromatography (HPIC) has been widely used for oxalate analysis and, more recently, for glycolate analysis. We describe a procedure for sample preparation in which the plasma ultrafiltrate is acidified during harvesting with a cation-exchange resin, and the chloride is removed before the ion chromatography, which is performed with a newly developed AS10 column. The same ultrafiltrate sample is analyzed for glycolate. For plasma oxalate, the mean recovery of sample in eluted fractions was 95-96%, and intraassay CV was 6.2-8.1%. The reference interval (mean ±2 SD) for men was 0.8-3.2 μmol/L and for women, 1.0-2.6 μmol/L For urinary oxalate, the reference interval for men was 175-560 μmol/day and for women, 107-432 μmol/day. For plasma glycolate, the mean analytical recovery was 96-98%, and the intra-assay CV was 2.4-6.2%. The reference interval for men was 1.9-7.5 μmol/L and for women, 1.4-7.4 μmol/L. For urinary glycolate, the reference interval for men was 0-1400 μmol/day and for women, 91-1001 μmol/day.