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At a Glance
Why Get Tested?
To help evaluate the health of your kidneys; to help diagnose kidney dysfunction or disease; to detect decreased blood flow to the kidneys
When to Get Tested?
When your results of a routine blood creatinine test and/or estimated glomerular filtration rate (eGFR) are not within the normal ranges; when you have signs and symptoms that may be due to kidney disease or damage or when you have a problem affecting the function of your kidneys, such as an obstruction within the kidney or acute or chronic kidney failure, or dysfunction due to another disease, such as congestive heart failure
Both a urine sample (24-hour collection) and a blood sample drawn from a vein in your arm
Test Preparation Needed?
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.