What Is EGRF in a Blood Test?

Doctors perform an estimated glomerular filtration rate test, or eGFR, to help determine the health of your kidneys. The kidneys are the organ that is responsible for filtering your blood and helping your body to maintain a healthy blood pressure level. Doctors check your blood for a chemical waste product called creatinine which is sloughed off by your muscles. The creatinine level, along with other factors such as your age, race, and sex are used to determine your eGFR.

Time Frame

Creatinine levels are not stable and may change from one day to the next. If there is a question regarding the health of your kidneys, your doctor may suggest the eGFR test be repeated after several months have passed.


The eGFR is not a valid test for people who are younger than 18 or older than 70. It is also not use for people who are pregnant, severely overweight or exceptionally muscular.


A eGFR score of less than 15 indicates imminent kidney failure that may require dialysis or kidney transplant.


If your eGFR score falls between 15 and 60, you may have kidney damage and will need to discuss options with your doctor.


Scores above 60 may indicate healthy kidneys. Your doctor may use other tests such as blood pressure and urine tests to insure your kidneys are functioning properly.