Phosphorus, 24 Hour, Urine
Use
This test is used for the evaluation of hypo- or hyper-phosphatemic states and in patients with nephrolithiasis. Approximately 80% of filtered phosphorus is reabsorbed by renal proximal tubule cells. The regulation of urinary phosphorus excretion is principally dependent on regulation of proximal tubule phosphorus reabsorption. Factors include diet, hormone levels, and certain medical conditions such as Fanconi Syndrome and hypophosphatemic Rickets.
Special Instructions
24-Hour urine volume in milliliters is required. Collect urine for 24 hours and refrigerate the specimen within 4 hours of completion. For non-electronic orders, complete and send the Renal Diagnostics Test Request form with the specimen.
Limitations
No significant cautionary statements were noted. Interpretation of urinary phosphorus excretion is dependent upon the clinical situation and should be interpreted with serum phosphorus concentrations.
FDA ApprovedNew York Approved
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 2779-7
- 2779-7
- 13362-9
- 3167-4
- 21458-5
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
4 mL
Minimum Volume
1 mL
Container
Plastic, 5 mL tube or a clean plastic aliquot container with no metal cap or glued insert
Collection Instructions
Collect urine for 24 hours. Refrigerate specimen within 4 hours of completion of 24-hour collection.
Causes for Rejection
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 14 days |
| Frozen | 30 days |