Estimated Glomerular Filtration Rate (eGFR), Creatinine-Based Calculation — Whole Blood
A blood-based calculation that estimates how well the kidneys filter waste, usually using the creatinine level and selected personal factors.
["Your eGFR is an estimate of kidney filtering function that helps identify and monitor kidney disease."]
Key facts at a glance
- LOINC
- 55766-0
- Short code
- EGFR c.2573T>G Bld/T Ql
- Synonyms
- EGFR c.2573T>G Bld/T Ql
- Category
- kidney
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 90
- Ref high
- 120
- Critical range
- 15 N/A – —
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- molgen
- CPT
- 82565
- SNOMED
- 247997009
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What is this test?
Estimated glomerular filtration rate, or eGFR, is a calculated measure of how well your kidneys remove waste from the blood. It is usually based on a blood creatinine measurement along with information such as age and sex.
Why might I need this test?
Clinicians use eGFR to evaluate and monitor kidney function, including chronic kidney disease, high blood pressure, diabetes, and other conditions that may affect the kidneys. It may also be used to help guide medication dosing and other care.
How is the test performed?
A blood sample is collected, and the laboratory measures creatinine or uses a previously reported creatinine result. The laboratory then calculates eGFR with a standard formula. The calculation is not a direct measurement of filtration.
How do I prepare for the test?
Fasting is generally not required unless your clinician gives specific instructions. Recent illness, dehydration, pregnancy, unusually high muscle mass, and certain medications can affect the result, so tell your clinician about anything that may be relevant.
Reference range
Normal: >90 mL/min/1.73m²N/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A lower eGFR may indicate reduced kidney filtration and can be seen with chronic kidney disease, dehydration, or some acute kidney problems. A higher value may occur with pregnancy or unusually high muscle mass. The result should be interpreted with other kidney tests, symptoms, and your medical history because eGFR is an estimate rather than a direct measurement.
Short name
eGFR
Frequently asked questions
Is eGFR the same as a creatinine test?
Does a low eGFR always mean I have kidney failure?
Can I improve my eGFR?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy