What Is a Urea Test?

According to Lab Tests Online, urea nitrogen is always present in small amounts in the blood of healthy individuals. Urea is a waste that is filtered by the kidneys to remove it from the blood and is excreted in the urine. There are medical conditions that can cause the kidneys to become ineffective in removing urea from the blood, and urea nitrogen levels can build to an unhealthy level. Testing can be done to see how high urea blood levels are and determine if there is a problem that will need extensive treatment.

What is a Urea Test?

• Testing of levels of urea in the blood is referred to as a blood urea nitrogen test, or BUN. When the liver breaks down protein it releases nitrogen, which goes on to combine with other molecules inside of the liver to form a substance called urea. Urea is not healthy when it exists in large amounts in the blood, so the kidneys filter it out of the blood and it is eliminated when an individual urinates. If the kidneys fail to filter urea out of the blood, too much urea accumulates. Testing for urea in the blood can be done through a simple blood test.

When is a Urea Test Ordered?

• A blood urea nitrogen test is occasionally ordered as a part of routine blood work. A BUN test may also be ordered if a physician is concerned there are problems with the functioning of an individual's liver or kidneys. Individuals with problems such as diabetes or kidney disease may have a blood urea nitrogen test done regularly to make sure the kidneys are not beginning to fail.

Why is a Urea Test Important?

• A blood urea nitrogen test is important because it helps to clearly indicate a problem with the kidneys. A BUN test can not only tell if an individual is in kidney failure or has kidney disease, it can also tell a lot about the functioning of an individual's body in general.

What do the Results of a Urea Test Mean?

• High levels of urea in the blood can be an indicator of a number of illnesses. High urea levels can mean an individual's kidneys are not working properly. This test result can also mean blood flow has been blocked from the kidneys because of heart problems, stress, or shock. Individuals who have a blockage preventing them from urinating properly or who are extremely dehydrated may have high levels of urea in the blood.

Factors that Can Affect Urea Test Results

• Individuals who eat excessive quantities of protein will have blood urea nitrogen tests that come back showing high levels of urea in the blood. On the other hand, individuals who eat little to no protein will show abnormally low levels of urea in the blood.