Creatinine & urea - what exactly are your "kidney values"?

[ Continues ] What are my kidney values?

Your so-called "kidney values" are the measured values, based on which you can typically see how well your kidneys still function. The term "kidney values" is mainly used to describe creatinine and urea. If you take it exactly, other values can also be changed depending on the kidney function.

What does creatinine do in my body?

Creatinine is a breakdown product from muscle metabolism and has been defined as a measure of kidney function. It is dependent on your muscle mass and you will not feel an increase in creatinine levels.

What is urea doing in my body?

Urea is a breakdown product of protein metabolism. It is usually excreted in the urine and - to a lesser extent - in the stool.

What happens when my kidneys stop working?

When your kidneys have reduced function, substances that are normally filtered out by the kidneys begin to accumulate in the body. These substances include urea and creatinine. As you may know, even with dialysis, you often have some residual kidney function, especially in the beginning.

What are the approximate target levels for creatinine and urea?

In women, the target range of creatinine is approximately between 0.50 - 0.90 mg/dl. In men, this is slightly higher, at 0.70 - 1.20 mg/dl.

For urea, depending on what units your lab report uses, the approximate targets are between 6 - 20 mg/dl or 2.1 - 8.9 mmol/l.

How can creatinine and urea be affected in therapy?

Creatinine is filtered out during renal replacement therapy. Depending on your physical activity, creatinine will always rise on dialysis-free days.

Urea is very well washed out during renal replacement therapy as well and actually serves as evidence of a good treatment. Therefore, this test is done regularly immediately before and after dialysis. Make sure you eat a healthy diet that is rich in protein to keep this parameter in its target range. Regular low urea levels at the beginning of dialysis often stem from a low protein diet and will affect your survival on dialysis.