Test ID DOXA Oxalate Analysis in Hemodialysate
Useful For
Determining the amount of oxalate removed during a dialysis session
Individualizing the dialysis prescription of hyperoxaluric patients
Method Name
Ion Chromatography (IC)
Reporting Name
Oxalate, Dialysate FluidSpecimen Type
Dialysate FluidContainer/Tube: Plastic, 10-mL urine tube (T068) or a clean, plastic aliquot container with no metal cap or glued insert
Specimen Volume: 5 mL
Collection Instructions: Adjust the pH of the specimen to 2.5 to 3.0 with 6N HCl.
Additional Information:
1. Patient should avoid taking vitamin C supplements for 24 hours prior to dialysis.
2. Nonacidified frozen hemodialysate delivered to the laboratory within 3 days from collection will be accepted and the following comment will be added to the result: In nonacidified hemodialysate stored frozen, oxalate values may increase spontaneously up to 30% (average 11% increase for dialysate oxalate stored for 48 hours, frozen, nonacidified).
Specimen Minimum Volume
2 mL
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Dialysate Fluid | Frozen | 14 days |
Clinical Information
Oxalate is a dicarboxylic acid, an end product of glyoxalate and glycerate metabolism that is excreted in the urine where it is a common component of kidney stones (up to 85%). Hyperoxaluria can be either genetic (eg, primary hyperoxaluria) or acquired/secondary (eg, enteric hyperoxaluria), and can lead to nephrocalcinosis and renal failure. Monitoring the adequacy of oxalate removal during hemodialysis can be useful in the management of patients with hyperoxaluria and renal failure, particularly following transplantation.
Reference Values
Not applicable
Cautions
Proper specimen processing and acidification are essential to obtain a quality result and avoid nonenzymatic generation of oxalate from ascorbate.
Day(s) Performed
Monday through Sunday; Continuously
Report Available
3 daysPerforming Laboratory

Test Classification
This test has been modified from the manufacturer’s instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
83945