What is creatinine?

Creatinine is a waste product of creatine, which is a chemical that the body uses to supply the muscles with energy. Creatinine is formed as a result of the natural breakdown of your muscle tissue and can then enter the blood.

Under normal conditions, your kidneys filter creatinine from your blood. Creatinine leaves the body through urine.

What is the creatinine clearance test?

The creatinine clearance is a test that allows your doctor to assess your kidney function. It is usually measured using both a blood test and a urine test. The creatinine clearance can also be estimated from a mathematical formula that will use the blood levels of creatinine along with other factors (such as your age, race, and gender).

Creatinine clearance testing determines your overall glomerular filtration rate (GFR), which reflect how well your kidneys are cleaning your blood.

Why do I need to have the creatinine clearance test?

Anyone can be at risk for a kidney disease at some point in time. However, some people are more at risk than others for developing kidney disease. You are at a higher risk for developing kidney disease if you are over 60 years old or if you have:

  • Diabetes
  • High blood pressure
  • A family history of kidney disorders
  • An African-American, Asian, Native American, or Pacific Islander background

Are there symptoms associated with elevated creatinine level?

Kidney disease tends to be silent and there are no symptoms in the early stages. However, as the disease progresses, you may experience swelling, fatigue, breathing problems, changes in how often you urinate, loss of appetite, nausea, itching, and a darkening of the skin.

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