Test Code LAB383 Creatinine with Estimated GFR
Useful For
Creatinine:
- Diagnosing and monitoring treatment of acute and chronic renal diseases
- Calculation of the fractional excretion of urine analytes
- Monitoring renal transplant recipients
Estimated Glomerular Filtration Rate (eGFR):
Serum creatinine measurement is used in estimating GFR for people with chronic kidney disease (CKD) and those with risk factors for CKD (diabetes, hypertension, cardiovascular disease, and family history of kidney disease).
Methodology
Kinetic Colorimetric (Jaffe)
Performing Laboratory
Bozeman Health Laboratory Services
Specimen Requirements
Specimen Type: Plasma or serum
Container/Tube: Light-green top (lithium heparin gel), red top, or gold top
Specimen Volume: 1 mL
Specimen Minimum Volume: 0.5 mL
Specimen Rejection: Icteric samples can produce bias. Highly icteric samples will be rejected.
Specimen Transport Temperature
Ambient/Refrigerated
Specimen Stability
Specimen Type | Temperature | Time |
---|---|---|
Plasma or Serum | Ambient | 7 days |
Refrigerated | 7 days | |
Frozen | 3 months |
Reference Values
Male: 0.60-1.40 mg/dL
Female: 0.50-1.00 mg/dL
eGFR: ≥60 mL/minute/1.73m2
(Includes estimated glomerular filtration rate (eGFR) calculation for all patients 18 years and older)
Additional Information
- eGFR is based on the Modification of Diet in Renal Disease (MORD) equation.
- If patient is African American, multiply result by 1.21.
- Calculation is only valid for patients >18 years of age.
- Expected values are based on a body surface area of 1.73 square meters, which is an accepted average body surface area.
- Antibiotics containing cephalosporin lead to significant falsepositive values
- Cefoxitin causes artificially high creatinine results
- Cyanokit (Hydroxocobalamin) may cause interference with results
- The presence of ketone bodies can cause artificially high results
Day(s) Test Set Up
Monday through Sunday
Test Classification and CPT Coding
82565