Creatinine Clearance
The Test Sample
What is being tested?
Creatinine is a chemical derived from creatine, a nitrogen-based organic compound used by muscles to store and transfer energy. The amount of creatinine produced in the body is dependent on muscle mass and is constant for an individual. It is removed from the body as blood passes through the kidneys. By measuring creatinine in the blood and in the urine, it is possible to determine the amount of blood filtered by the kidneys in a measured period of time. A calculation is made based on the amount of creatinine in the urine, the time period of collection, and the amount of creatinine in the blood serum or plasma.
How is the sample collected for testing?
The test requires a 24-hour urine collection and a blood sample taken either at the beginning or end of the urine collection. The blood sample is collected by needle from a vein in the arm.
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
If you don't know what a word or a medical term means, try the
Mondofacto Online Medical Dictionary
.
