Oxalate, 24 Hr Urine

Test Code

Quest Code

CPT Codes

CPT code 81050 may be added at an additional charge for volume measurement

Preferred Specimen
10 mL aliquot of a 24-hour urine, collected in a plastic, leak-proof urine container

Patient Preparation
Patient should refrain from taking excessive amounts of ascorbic acid or oxalate-rich foods (i.e., spinach, coffee, tea, chocolate, rhubarb) for at least 48 hours prior to collection period

Minimum Volume
2 mL

Please submit a 10 mL aliquot of a 24-hour collection. Collect urine with 25 mL of 6N HCL to maintain a pH below 3. Refrigerate during and after collection.
Adjust pH to < 3.0 with 25 mL 6N HCl before aliquoting for testing.

Transport Temperature
Room temperature

Specimen Stability
Room temperature: 7 days
Refrigerated: 7 days
Frozen: 24 days

Spectrophotometry (SP)

Setup Schedule
Set up: Tues-Sat; Report available: 1-3 days

Reference Range
3.6-38.0 mg/24 h

Clinical Significance
Excessive oxalates in the urine may lead to oxalate kidney stones. Hyperoxaluria may be due to a rare inherited metabolic disorder in which the body produces excess of the salt oxalate, leading to stone formation.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.