Creatinine
Use
A renal function test used in eGFR calculation.2
Special Instructions
Creatinine values must be interpreted in conjunction with clinical information to assess the kidney's filtration function accurately. Collect serum or plasma, separating them from cells within 45 minutes of collection to ensure accurate results. Avoid using oxalate, EDTA, or citrate plasma.
Limitations
Creatinine levels may not rise as quickly as other markers with reduced renal blood flow. The test becomes abnormal only when a significant number of nephrons have ceased functioning. Antibiotics containing cephalosporins can lead to false positives if samples are drawn within four hours of administration. Cefoxitin therapy in severe renal disease patients may also yield unreliable creatinine results. Samples need careful handling to avoid interferences from lipemia, hemolysis, and bilirubin.
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 2160-0
- 2160-0
- 98979-8
Result Turnaround Time
1 day
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.7 mL
Container
Red-top tube, gel-barrier tube, or green-top (lithium heparin) tube
Collection Instructions
Separate serum or plasma from cells within 45 minutes of collection.
Storage Instructions
Maintain specimen at room temperature.
Causes for Rejection
Hemolysis; improper labeling
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |