Estimated Glomerular Filtration Rate; eGFR
How is it used?
The eGFR is used to screen for and detect early kidney damage and to monitor kidney status. It is performed by ordering a creatinine test and calculating the estimated glomerular filtration rate. The creatinine test is ordered frequently as part of a routine comprehensive metabolic panel (CMP) or basic metabolic panel (BMP), or along with a blood urea nitrogen (BUN) test whenever a health practitioner wants to evaluate the status of a patient’s kidneys. It is ordered to monitor those with known chronic kidney disease (CKD) and those with conditions such as diabetes and hypertension that may lead to kidney damage.
When is it ordered?
The eGFR can be determined, with no extra testing, at the same time that a blood sample is sent for a creatinine measurement. The National Kidney Foundation has recommended that it be calculated automatically every time a creatinine test is done. A creatinine test and eGFR may be ordered any time that a health practitioner wants to evaluate a person’s kidney function as part of a health checkup or if kidney disease is suspected. Warning signs of kidney disease may include:
- Swelling or puffiness, particularly around the eyes or in the face, wrists, abdomen, thighs, or ankles
- Urine that is foamy, bloody, or coffee-colored
- A decrease in the amount of urine
- Problems urinating, such as a burning feeling or abnormal discharge during urination, or a change in the frequency of urination, especially at night
- Mid-back pain (flank), below the ribs, near where the kidneys are located
- High blood pressure (hypertension)
As kidney disease worsens, symptoms may include:
- Urinating more or less often
- Feeling itchy
- Tiredness, loss of concentration
- Loss of appetite, nausea and/or vomiting
- Swelling and/or numbness in hands and feet
- Darkened skin
- Muscle cramps
An eGFR may be ordered periodically when a person has a chronic kidney disease (CKD) or a condition such as diabetes or hypertension that is associated with kidney damage.