Test ID: HYOX
Hyperoxaluria Panel, Urine

Distinguishing between primary and secondary hyperoxaluria

Distinguishing between type I and type II primary hyperoxaluria

Distinguishing between primary and secondary hyperoxaluria.

Increased urinary oxalate frequently leads to renal stone formation. Identification of the cause of increased urinary oxalate is important in the evaluation of the patient with renal oxalate stones or renal insufficiency due to hyperoxaluria and has important implications in therapy and prognosis.

Hyperoxalurias have been classified as primary (genetically determined) and secondary. Primary hyperoxalurias are rare autosomally inherited genetic diseases. Type I, a deficiency of peroxisomal alanine:glyoxylate transaminase, is characterized by increased urinary oxalic, glyoxylic, and glycolic acids. Some type I hyperoxaluric patients respond to supplementary pyridoxine therapy. Type II is due to a defect in hydroxypyruvate metabolism (D-glyceric acid dehydrogenase deficiency) and is characterized by an increase in urinary oxalic and glyceric acids.

Secondary hyperoxalurias are due to hyperabsorption of oxalate (enteric hyperoxaluria); total parenteral nutrition in premature infants; ingestion of oxalate, ascorbic acid, or ethylene glycol; or pyridoxine deficiency and may respond to appropriate therapy.

GLYCOLATE

0-31 days: 0-57 mg/g creatinine

1-5 months: 0-54 mg/g creatinine

6-12 months: 0-60 mg/g creatinine

1-5 years: 0-89 mg/g creatinine

> or =6 years: 0-78 mg/g creatinine

GLYCERATE

0-31 days: 0-38 mg/g creatinine

1-5 months: 0-71 mg/g creatinine

6-12 months: 0-56 mg/g creatinine

1-5 years: 0-17 mg/g creatinine

> or =6 years: 0-8 mg/g creatinine

OXALATE

0-31 days: 0-301 mg/g creatinine

1-5 months: 0-398 mg/g creatinine

6-12 months: 0-280 mg/g creatinine

1-5 years: 0-128 mg/g creatinine

6-10 years: 0-72 mg/g creatinine

> or =11 years: 0-56 mg/g creatinine

GLYOXYLATE

0-31 days: 0.0-7.9 mg/g creatinine

1-5 months: 0.0-11.4 mg/g creatinine

6-12 months: 0.0-5.5 mg/g creatinine

1-5 years: 0.0-3.9 mg/g creatinine

> or =6 years: 0.0-2.9 mg/g creatinine

Increased concentrations of oxalate and glycolate indicate type I hyperoxaluria.

Increased concentrations of oxalate and glycerate indicate type II hyperoxaluria.

Increased concentrations of oxalate with normal concentrations of glycolate and glycerate indicate secondary hyperoxaluria.

Ascorbic acid will falsely elevate oxalic acid results.

1. Monico CG, Persson M, Ford GC, et al: Potential mechanisms of marked hyperoxaluria not due to primary hyperoxaluria I or II. Kidney Int 2002;62:392-400

2. Danpure CJ: Primary hyperoxaluria. In The Metabolic Bases of Inherited Disease. 8th edition. Edited by CR Scriver, AL Beaudet, WS Sly, et al. New York, McGraw-Hill Book Company, 2001, pp 3323-3367

3. Byrd DJ, Latta K: Hyperoxaluria. In Physician’s Guide to the Laboratory Diagnosis of Metabolic Disease. Edited by N Blau, ED Chapman. Hall Medical, 1996, pp 377-390

4. Fraser AD: Importance of glycolic acid analysis in ethylene glycol poisoning. Clin Chem 1998;44(8):1769

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