Oxalate, Random, Urine
Use
Monitoring therapy for kidney stones using random urine specimens. Identifying increased urinary oxalate as a risk factor for stone formation. Diagnosis of primary or secondary hyperoxaluria. Random urinary collections normalized to creatinine may be useful in children under 16 years old who cannot collect 24-hour specimens; however, 24-hour collection is preferred.
Special Instructions
If not ordering electronically, complete, print, and send a Renal Diagnostics Test Request (T830). Patient should avoid large doses of vitamin C (>2 g/24 h) prior to specimen collection. Use 10 mL plastic tube or clean plastic container with no metal cap. No preservative. Specimen pH should be between 4.5 and 8; specimens with pH > 8 indicating bacterial contamination will be cancelled. Do not adjust pH. All specimens evaluated for suitability. Mayo Clinic Laboratories modified manufacturer's instructions and performance characteristics determined under CLIA requirements. Not FDA-cleared or approved. A timed 24-hour urine collection is preferred; random is for children under 16.
Limitations
Ingestion of ascorbic acid (> 2 g/day) may falsely elevate measured urinary oxalate. Specimens with pH above 8 may indicate bacterial contamination and will result in cancellation. The test is a modified version of the kit requiring careful specimen handling. Performance characteristics were determined by Mayo under CLIA, not FDA. Random collections are less preferred and primarily useful in children.
New York Approved
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 15086-2
- 2161-8
- 15086-2
- 2700-3
- 13483-3
Result Turnaround Time
3-5 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
7 mL
Minimum Volume
6 mL
Container
10‑mL plastic tube or a clean, plastic container with no metal cap
Collection Instructions
Collect a random urine specimen. No preservative. Specimen pH should be between 4.5 and 8; specimens with pH above 8 may indicate bacterial contamination and testing will be cancelled. Do not attempt to adjust pH.
Patient Preparation
Avoid taking large doses (>2 g orally/24 hours) of vitamin C prior to specimen collection.
Causes for Rejection
Specimens with pH above 8 indicating bacterial contamination; assessed for suitability at Mayo Clinic Laboratories.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Ambient: 72 hours |
| Refrigerated | Refrigerated (preferred): 14 days |
| Frozen | Frozen: 14 days |