A common blood or urine test, the blood urea nitrogen (BUN) (Urea) test reveals important information about how well your kidneys are working. A BUN test measures the amount of urea nitrogen that's in your blood.

 creatinine is a test for the following reasons: To make a diagnosis if you have signs or symptoms of kidney disease. To screen for kidney disease if you have diabetes, high blood pressure or other conditions that increase the risk of kidney disease.

This test may be done to help determine the cause of a high Uric acid level in the blood. It may also be done to monitor people with gout, and to choose the best medicine to lower the uric acid level in the blood. Uric acid is a chemical created when the body breaks down substances called purines.