Abstract

Measurement of oxalate in urine is important for diagnosis of primary hyperoxaluria and the secondary forms resulting from excessive intake or abnormal intestinal absorption of oxalate. Determination of glycolic acid is essential for diagnosis of primary hyperoxaluria type I (PH I), caused by low or absent activity of the liver-specific peroxisomal alanine:glyoxylate aminotransferase. Primary hyperoxaluria type II (PH II) is caused by low or absent activity D-glycerate dehydrogenase and hydroxypyruvate reductase activity, leading to elevated urinary excretion of both oxalate and L-glyceric acid. Ion chromatography HPLC is the method of choice the quantification of oxalate, glycolate, and glycerate and use of urinary filter spots is a practical alternative approach for the collection and safe transport of samples to be analyzed for many metabolic disorders.