Kidney Function Tests: Creatinine, eGFR, and More
Kidney function tests measure how well the kidneys filter waste from the blood. Common markers include creatinine, estimated glomerular filtration rate (eGFR), and blood urea nitrogen (BUN). Urine tests such as the albumin-to-creatinine ratio can detect early kidney damage before filtration changes are obvious. Reduced kidney function may produce no symptoms until it is advanced, which is why testing matters for people with diabetes, high blood pressure, or a family history of kidney disease.
Key Takeaways
- Kidney function tests measure how well the kidneys filter waste from the blood.
- Common markers include creatinine, eGFR, and blood urea nitrogen (BUN).
- Urine tests such as the albumin-to-creatinine ratio can detect early kidney damage.
- Reduced kidney function may have no symptoms until it is advanced.
- Results are interpreted with blood pressure, diabetes status, and other factors.
Frequently Asked Questions
What blood test checks kidney function?
Creatinine and eGFR are the main blood markers. A metabolic panel often includes them along with BUN.
What is eGFR?
The estimated glomerular filtration rate is a calculation based on creatinine that estimates filtering capacity.
Can I order kidney function tests without a doctor?
Yes, kidney panels are available through direct-access testing.
Do I need to fast for kidney tests?
Fasting is usually not required for creatinine or eGFR, though a full metabolic panel may be done fasting.
Sources
Reviewed by the LabWalkIns Editorial Team
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