The liver breaks down proteins in your food — and while doing so, the liver produces blood urea nitrogen, also known as BUN. Your liver releases this BUN into your blood, which eventually ends up in your kidneys. Your kidneys remove BUN when they are healthy, generally leaving a small amount in your blood. But most of the time, your healthy kidneys throw it away by flushing it from your body through urine.
However, if the kidneys do not function properly, blood levels of nitrogen and urea will rise. If you need to know the exact amount of urea currently present in your blood, you should take a blood urea nitrogen test called BUN for short.
About BUN test
The BUN test is a diagnostic procedure for checking the health of the kidneys. Your blood sample will be tested in the laboratory. You can also check the creatinine level.
High levels of urea and nitrogen in cases of kidney problems, heart disease, and dehydration. In contrast, BUN levels tend to be lower in patients suffering from liver disease.
However, BUN reports can show high values due to excessive intake of protein-rich foods, but can be low in late pregnancy. Since it is done with a creatinine test, your doctor will compare both results to diagnose your exact problem.
Risk factors associated with the dumpling test
- If the patient has blood clotting problems or is taking anticoagulants, the spots punctured to take blood samples can bleed heavily.
- For diabetics, it may take some time for the puncture bruise to heal.
- Excessive blood builds up under the surface of the skin, which can cause the puncture site to turn red.
How to prepare for BUN test?
No special preparation is required before the BUN test. You should follow the instructions given by the doctor who recommended the test.
However, you should notify your doctor about all the medications you are currently taking to avoid complications.
Some drugs, such as tetracycline, methyldopa, and carbamazepine, can increase BUN levels, so doctors may suggest discontinuing these drugs for the time being. You should also limit your daily intake of fish, meat, and other protein-rich foods at least 24 hours before this test.
What do you expect from the BUN test?
The BUN test collects only a very small amount of blood. The laboratory technician ties a band around the arm and dilates the veins to draw blood with a sterile syringe. There will be a slight stinging sensation during this process, which should soon subside. Bandage this perforated part of the skin to stop bleeding and heal immediately.
Blood samples are then tested with the reagents needed to assess the levels of urea and nitrogen in the blood. Immediately after taking a blood sample, you can leave as long as you do not have any physical problems after the test.
Possible results from your BUN test
BUN test report values are expressed as milligrams (mg / dL) per deciliter. Standard BUN levels depend on the patient’s age and gender.
If the test report of an adult male patient turns out to be normal, his BUN level should be between 8 mg / dL and 24 mg / dL.
Normal BUN reports for adult female patients should have values in the range of 6 mg / dL to 21 mg / dL. Children up to 17 years should have BUN levels of 7 mg / dL to 20 mg / dL.
However, we find that the average BUN value for older men and women over the age of 60 is slightly higher than the average BUN level for young adults. If your BUN test report reveals a value that is much higher or lower than the normal range, you may be ill.
High levels may indicate that:
- Kidney damage
- Urinary tract obstruction
- heart attack
- Congestive heart failure (when the heart does not pump blood to the body as it should)
- Gastrointestinal bleeding (bleeding in the gastrointestinal tract such as the esophagus, stomach, and intestines)
Low BUN levels are rare. If the BUN level is low, it may indicate that:
- Liver disease
- Excessive water (too much water)
- Malnutrition (if your diet doesn’t have enough nutrients, or your body doesn’t get them well)
However, the BUN test is not a way to diagnose these problems and may require further testing.
When do you see a doctor?
If the BUN test report shows much higher values than the normal range for your age group, it could be a sign of some underlying health condition. You may be suffering from heart problems, renal failure, dehydration, gastrointestinal damage, or obstruction of the urinary tract.
Abnormally high BUN levels can be due to the reaction of some medications taken to cure other illnesses. If your report shows a BUN value that is much lower than the normal range, it may indicate that you are suffering from liver damage or malnutrition.
BUN levels can also be lower than expected if you eat too much protein-rich foods or drink too much water. However, BUN levels can also become abnormal during pregnancy.
If your BUN test report shows a high or low BUN value, it is advisable to see a doctor to determine the exact cause of this result.
Request a reservation at Apollo Hospital
To make a reservation, please call 1860-500-1066.
Frequently Asked Questions (FAQ)
Is the BUN test a sign of kidney damage?
The BUN test is not just about detecting kidney problems. There are multiple reasons for elevated blood urea and nitrogen levels. Therefore, you do not have to worry about kidney health when your doctor recommends performing a BUN test.
How can I confirm renal failure with a BUN test?
The BUN test is usually done in conjunction with the creatinine test, so doctors can compare both results to determine kidney condition. The presence of large amounts of creatinine, which has high BUN levels in the blood, may indicate that the kidneys are not functioning properly.
How does the BUN test contribute to your kidney treatment?
When a patient undergoes peritoneal dialysis and hemodialysis, the doctor needs a current blood test report to monitor treatment and response.
The BUN test report provides the levels of urea and nitrogen in the patient’s blood and also shows the progression of the condition after dialysis.Therefore, the doctor can decide whether to continue dialysis.