Creatinine Clearance, Serum and 24-Hour Urine
Use
The Creatinine Clearance test measures the efficiency of the kidneys in filtering creatinine, which can be used to estimate the glomerular filtration rate (GFR). This test is useful for diagnosing and monitoring kidney function and is particularly important for patients with risk factors for chronic kidney disease such as diabetes, hypertension, cardiovascular disease, or a family history of kidney disease. The estimated GFR is calculated using the CKD-EPI equation which does not require adjustments for weight, height, or race, making it widely applicable.
Special Instructions
Not provided.
Limitations
Creatinine clearance may overestimate true glomerular filtration rate (GFR) by 10% to 15% due to proximal tubular secretion of creatinine. Accuracy is highly dependent on complete and accurately timed urine collection. Results can be skewed in patients with elevated levels of certain substances, such as N-acetyl-p-benzoquinone imine (a metabolite of acetaminophen), N-acetylcysteine, and metamizole.
FDA ApprovedNew York Approved
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
Estimated GFR
SignatureCreatinine
Analyte
LOINC Codes
- 58446-6 - Creat 24H Cl BSA adj Pnl Ur+SerPl
- 20624-3 - Creat 24h Ur-mCnc
- 13362-9 - Specimen collect Time Ur
- 3167-4 - Specimen vol 24h Ur
- 12195-4 - Creat Cl/1.73 sq M 24h Ur+SerPl-ArVRat
- 2160-0 - Creat SerPl-mCnc
- 98979-8 - eGFRcr SerPlBld CKD-EPI 2021
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
Serum gel (preferred) or Red top
Collection Instructions
Centrifuge and aliquot serum into plastic vial. Label specimen as serum.
Causes for Rejection
Gross hemolysis, gross lipemia
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | preferred |
| Refrigerated | preferred |
| Frozen | OK |