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At a Glance
Why Get Tested?
To assess kidney function and diagnose, stage, and monitor chronic kidney disease (CKD)
When to Get Tested?
With a blood creatinine test as part of a routine health exam or when your healthcare practitioner thinks that you may have kidney damage or that you may be at risk for developing kidney disease
A blood sample drawn from a vein in your arm; the eGFR is a calculated estimate of the actual glomerular filtration rate and is based on your blood creatinine level along with other variables such as your age, sex, and race, depending on the equation used.
Test Preparation Needed?
This test uses a blood creatinine level to calculate a result. You may be instructed to fast overnight or refrain from eating cooked meat; some studies have shown that eating cooked meat prior to testing can temporarily increase the level of creatinine.