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Clinical Laboratory Test:
serum — urea nitrogen

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Urea nitrogen (BUN) is a measure of the amount of nitrogen in the form of urea in the blood. It is a measure of kidney function and is often used to evaluate kidney disease.

The test for urea nitrogen is typically performed on a sample of the patient's serum, which is the liquid portion of the blood. The sample is usually obtained by drawing blood from a vein in the arm. The sample is then sent to a laboratory for analysis.

In the laboratory, the sample is tested using a colorimetric method. This method involves adding a reagent to the sample, which causes a color change. The color change is then measured and compared to a standard to determine the amount of urea nitrogen present in the sample.

  • blood urea nitrogen
  • BUN
  • urea
Other Sample Sources for This Test
Some Diseases Associated with an Abnormal Urea Nitrogen
Detailed Laboratory Testing Information (use the custom search buttons below to find details on these topics)

All of the following must be considered when interpreting clinical findings and are too extensive to be covered on this site: