BUN stands for blood urea nitrogen. It is a laboratory test carried out for verifying the kidney function. The article given below deals with the significance, causes, and symptoms of elevated presence of urea in the blood.
The BUN test measures the amount of nitrogen in the blood, that comes from urea. Urea is a waste product formed in our body during protein metabolism. It is produced in the liver, filtered in the kidneys, and then flushed out of the body through urine. The BUN test is performed to check whether the kidneys are functioning properly or not. When the physician suspects kidney failure or disease, he prescribes this test. If the patient is already suffering from a kidney problem, this test may help in analyzing the results of the treatment provided by the physician.
If the BUN levels are not normal, they indicate a flaw in the body’s flushing system. High level of BUN is a sign of kidney dysfunction, while low BUN levels can indicate liver problems. Sometimes the BUN test is also done along with a blood creatinine test. Creatinine is also a waste product that is filtered by the kidneys. So, high levels of creatinine can indicate kidney damage. Both these tests can be used together to find out the urea nitrogen to creatinine ratio in the blood. The physician may also ask to perform this test to diagnose other health ailments, like urinary tract obstruction, congestive heart failure, liver disease, etc. Let us take a look at the causes of elevated levels of blood urea nitrogen.
Causes of High BUN Levels
BUN level changes with age. It is very low in babies, and can be higher in case of adults aged 60 years and above. Men usually have higher amount of nitrogen in the blood, as compared to women. The normal range is 7 to 20mg/dL, and any reading above or below these values can indicate high or low BUN levels, respectively. Elevated level of BUN is also referred to as azotemia. One of the major causes of high creatinine and blood nitrogen levels is improper kidney function. Healthy kidneys can filter all the urea passed to them through the bloodstream from the liver, while damaged kidneys are unable to do so. Dehydration could be another cause, and to confirm it, the urea nitrogen to creatinine ratio is taken. This is because, when the BUN level is high due to dehydration, creatinine levels are normal.
Diabetes or hypertension can be the causes of heightened levels of BUN and creatinine. Even some medications, like antibiotics, anti-inflammatory medicines, and gout medication, affect these levels. High protein diet and heart failure are some other causes. Given below is a list that will summarize the major causes.
- Congestive heart failure
- Excessive protein levels in the gastrointestinal tract
- Kidney disease
- Kidney failure
- Urinary tract obstruction
- Gastrointestinal bleeding
- High protein diet
- Stress or shock
Though urea is not too toxic in nature, its presence in the blood, in high amounts, can show certain symptoms. Dry and itchy skin, insomnia, nausea, fatigue, etc., are some of the common symptoms.
BUN In Pets
Not just in humans, but large amount of urea in blood can be an indication of kidney dysfunction in dogs too. Healthy pets usually display low or normal levels of BUN, but those with kidney problems show a drastic elevation in these levels. Veterinarians usually carry the BUN test for dogs with kidney problems, to test whether the treatment provided is effective or not.
Hence, if you are suffering from any of the problems mentioned in this article, get a BUN test done, and confirm whether your blood urea nitrogen levels are normal or not.
Disclaimer: This article is for informative purposes only and not intended to replace the advice offered by an expert on the subject.