GLOMERULAR FILTRATION RATE (EGFR)

Glomerular Filtration Rate (eGFR)

What it is

The Glomerular Filtration Rate (eGFR) test estimates how well your kidneys are filtering waste and excess fluid from the blood. It is calculated using your serum creatinine level, age, sex, and sometimes race. eGFR is one of the most important indicators of kidney health and helps in the detection and monitoring of chronic kidney disease (CKD).

Uses

This test is used to:

• Assess overall kidney function.
• Detect early stages of chronic kidney disease (CKD).
• Monitor progression of kidney disease over time.
• Guide decisions about medication dosing in patients with reduced kidney function.
• Evaluate kidney function in patients with diabetes, hypertension, or other risk factors.

Symptoms That May Lead to the Test

Doctors may recommend an eGFR test if you show signs of kidney disease such as swelling in legs or feet, high blood pressure, frequent urination, foamy or bloody urine, unexplained fatigue, nausea, or loss of appetite. It is also ordered routinely in people with diabetes or hypertension to screen for kidney complications.

Abnormal Results

Normal eGFR: 90 mL/min/1.73 m² or higher indicates normal kidney function.

Mildly Reduced eGFR: 60–89 mL/min/1.73 m² may indicate early kidney damage, especially if other signs of CKD are present.

Moderately to Severely Reduced eGFR: 15–59 mL/min/1.73 m² suggests significant kidney damage (CKD stages 3–4).

Very Low eGFR: Below 15 mL/min/1.73 m² indicates kidney failure (end-stage renal disease) and often requires dialysis or kidney transplant.

Risks

There are no direct risks from the eGFR calculation itself. The test requires a blood draw for serum creatinine measurement. Risks are minimal, limited to mild pain, bruising, or dizziness at the puncture site, which usually resolve quickly.