Why it's doneBy Mayo Clinic staff
You may have a blood urea nitrogen test if your doctor suspects that you have kidney damage, or if your kidney function needs to be evaluated. If you're receiving hemodialysis or peritoneal dialysis, you may have a BUN test to help determine the effectiveness of dialysis treatment.
If kidney problems are the primary concern, when your blood is tested for urea nitrogen levels, it's likely it will also be tested for creatinine levels. Creatinine is another waste product that healthy kidneys filter out of your body in urine. High levels of creatinine may be a sign of kidney damage.
Your doctor may also order a BUN test as part of a blood test group to help diagnose a number of other conditions, such as liver failure, urinary tract obstruction, congestive heart failure or gastrointestinal bleeding. But an abnormal BUN test result alone doesn't diagnose any of these conditions.
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