The urea test is a blood test that identifies the value of urea levels in the circulation, which can be through the direct dosage of urea or the indirect dosing, which is the blood urea nitrogen test.
Urea is a substance produced by the liver, as a result of the digestion of protein from the diet, which, if it is in excess can be toxic to the body, causing uremia. Know what uremia and symptoms are.
Usually urea examination is requested along with the creatinine test because, together, these tests may indicate how well the kidneys are working for the filtration of blood.
Reference values of urea in the test
The normal values of urea are:
- From 10 to 40 mg / dl or 2.5 to 6.4 mmol / L, for adult men and women;
The normal values of the urea nitrogen test, or BUN, are:
- From 8 to 24 mg / dl for adult men;
- From 6 to 21 mg / dl for adult women.
These values may vary slightly according to the laboratory, therefore, the reference values on the examination paper should be checked.
It is not necessary to prepare or be fasted before the examination, which is collected like any other blood test by the laboratory.
What does the test result mean?
The urea test result should be evaluated by the general practitioner or nephrologist, but usually when it is within the reference values indicates that the test is normal.
1. High urea
Increased urea may indicate kidney problems, especially when cretinin is also elevated, due to kidney failure, which is a disease that impairs kidney function and arises from high blood pressure, diabetes, infections or dehydration, for example. Learn more about kidney failure and how to treat it.
However, there are some conditions that can also elevate urea, even with the correct functioning of the kidneys, such as cancer, infections, liver changes or excess protein in the diet.
2. Low urea
Urea may be low and may not indicate diseases or conditions of concern. However, it may be due to a lack of protein in the diet, malnutrition, pregnancy, poor absorption of the intestine or liver failure to metabolize protein, such as in liver failure.
How to Lower Urea
To lower urea, it is necessary to treat kidney failure, through medications prescribed by the nephrologist, usually to control the pressure and amount of urine, and with a balanced diet in salt, liquids, vegetables and meat. See guidelines for what diet should be in kidney failure.
However, in some more severe cases, dialysis is required to normalize the levels of urea, creatinine and other blood salts, such as sodium and potassium.
