Tag Archives: muscle

I was told my serum creatinine level was high. What does that mean and why should I see a kidney doctor about it? First of all “serum creatinine” is a blood test. In order to this test a sample of blood is drawn from a vein. This test is mostly done in the labs (not in the office). The test for serum creatinine measures a compound which is called creatinine. Creatinine is a byproduct of energy metabolism expenditure by muscles. The more muscle a person has the more creatinine will gets released to the blood and this is why his or her serum creatinine will be on the higher end of normal. But more than muscle mass serum creatinine is determined by the filtering function of kidneys. We use this test (serum creatinine) not as indicator of muscle mass but as an indicator of kidney function.

How these two (serum creatinine and kidney function) relate? As you know as blood passes through kidneys some of chemicals in blood gets filtered out into urine. One of these chemicals is creatinine. If kidney function deteriorates (such as in kidney disease) the filtration function of kidneys deteriorates as well. In this case creatinine does not get filtered in urine in normal amount and its concentration in blood increases.

If you look at the blood test you will see this test written and reported as: “Cr”, “Creat” or “Creatinine”.

If you have any further question please contact Dr. Atef, kidney specialist in Dallas.