Also called BUN, Blood urea nitrogen, serum BUN
Summary of BUN
Important information about your kidney function is revealed by a common blood test called BUN (blood urea nitrogen test). The quantity of urea nitrogen in the blood is measured using the blood urea nitrogen test.
In this article we are going to discuss what BUN test is, how BUN test is carried out, risk factors, normal levels of BUN, what high or low levels of blood urea nitrogen mean and treatment for blood urea nitrogen abnormalities. Continue reading if you are looking to understand the health effects of blood urea nitrogen.
This is how your body normally makes and excretes blood urea nitrogen:
- After your liver breaks down proteins used by cells in your body, your liver produces a nitrogen containing compound called ammonia.
- Urea which is a waste chemical formed when certain elements such as oxygen, hydrogen, and carbon combine with nitrogen.
- Urea flows through the bloodstream from the liver to the kidneys.
- Urea and certain waste products are filtered from the blood by healthy kidneys.
- Waste products filtered from blood exit your body through your urine.
If blood urea nitrogen level is higher than normal from a BUN test results, it can be an indication that your kidneys could be malfunctioning.
What is a BUN (blood urea nitrogen) test?
A measure of the quantity of urea nitrogen in the blood is done with a BUN (blood urea nitrogen) test. When the liver degrades proteins it produces waste products called urea nitrogen. It is excreted from the body in the urine after being filtered by the kidneys out of the blood. Your liver may not degrade protein as it should if it is not healthy. And your kidneys may not be filtering urea properly if they are not healthy. A resulting higher levels of blood urea nitrogen in the body can be because of these problems.
Your doctor determine the health state of your kidneys with a blood urea nitrogen or BUN levels. Alongside other tests, blood urea nitrogen test can be used to help figure out how good your kidney disease treatment is working and even to diagnose kidney disease.
What is a blood urea nitrogen test used for?
The blood urea nitrogen test is often part of a series of tests known as CMP (comprehensive metabolic panel). This can help monitor or diagnose kidney disorders or diseases.
Why is a BUN biochemistry test performed?
During a BMP (basic metabolic panel) evaluation OR CMP (comprehensive metabolic panel), your doctor may recommend blood urea nitrogen test.
If you are at increased risk of kidney disease, your doctor may also recommend a blood urea nitrogen test. The following factors may increase your risk even though there are no symptoms in the early stages of kidney disease:
- A history of kidney disorder in the family.
- Heart disease
- Hypertension (High blood pressure).
It’s a good idea to have a blood urea nitrogen BUN test if you have symptoms of end-stage renal disease. Symptoms of advanced kidney disorder can include:
- Loss of appetite
- Frequent need for urination
- Foamy urine
- Blood in the urine.
- Swelling, especially in the hands, ankles, and feet.
How do I prepare for the test?
Tell your doctor what medicines you are taking before the blood urea nitrogen (BUN) test. A doctor may ask you to stop taking any medicines for a period of time if he/she suspects that these substances can affect your BUN test results.
You can eat and drink if you’re only getting a BUN test. However, your health care provider may give you instructions like fasting before the blood urea nitrogen test if you have other blood tests to do.
What happened during blood urea nitrogen test?
The laboratory technician will collect a blood sample from the back of your hand or a vein in your arm. As the needle penetrates your skin, you may feel a slight burning sensation.
You can go back to your daily activities right away even though it may hurt a bit afterward.
Your blood sample is then send to the laboratory for testing by the nurse. Depending on how the lab tech works, you can get your results in a few days.
Does blood urea nitrogen test have any risks?
They are some risks associated with getting a blood diagnostic tests with a syringe. These include dizziness, bleeding, bruising, and infection. You may feel a mild pain or sting when the needle enters your hand or arm. The area may get sore afterwards.
What are the normal levels for blood urea nitrogen?
Normal levels of blood urea nitrogen vary with sex and age.
- Between 7 and 20 mg/dL for children from 1 to 17 years old.
- Between 6 and 21 mg/dl for adult females.
- Between 8 and 24 mg/dL for adult males.
What blood urea nitrogen level signifies a kidney failure?
Doctors do not use blood urea nitrogen to detect a kidney failure. However, you probably have kidney failure if your creatinine (a waste product of the breakdown of muscle tissue) is also high, and if your blood urea nitrogen level is higher than baseline.
What can affect blood urea nitrogen test results?
For many reasons, your blood urea nitrogen level can increase, including when your kidneys are functioning properly. These reasons includes:
- High protein containing diet
- Use of Steroids.
Therefore, a measure of kidney health that is more reliable is the relationship between blood urea nitrogen levels and creatinine levels.
What Blood urea nitrogen test results mean?
The quantity of blood urea nitrogen is the result of a BUN test. Between 7 and 20 mg/dl is considered to be the normal range (a deciliter is about 3.4 ounces and a mg is a very small amount: just over 28,000 per ounce.)
Contact your health care provider if your test results are outside of this range.
A blood urea nitrogen value above or below the normal range does not always indicate a disorder since several factors can affect the results of a blood urea nitrogen test.
What is high blood urea nitrogen?
Kidneys that are not working as they should can result to a high blood urea nitrogen level. You may still have high blood urea nitrogen (BUN) levels even if your kidneys are working properly for the following reasons:
- Aging (children and infants have lower urea levels).
- Protein-rich diet.
- A blockage in the renal system that prevents you from urinating.
- Certain medications, including tetracyclines, methotrexate, and carbamazepine.
- Myocardial infarction.
- Gastrointestinal bleeding.
What does low blood urea nitrogen mean?
Your BUN level may be low even though low BUN values are not common for the following reasons:
- Too much water in the body.
- Low protein diet.
- Liver disorder.
- Small body type.
How to fix a high blood urea nitrogen values?
Elevated BUN levels are not "fixed" by doctors. They figure out why a person's kidney function is abnormal and fix the problem. Changing your diet is however the easiest way to reduce high BUN levels.
Be sure to drink plenty of fluids if you do not have kidney disorder and are not on kidney dialysis: relatively low serum creatinine in spite of an isolated increase in blood urea nitrogen may indicate dehydration. Men should drink about 3 liters (13 glasses) of water per day. Females should drink 2.2 liters (about 9 glasses) of fluid a day.
You can equally reduce high blood urea nitrogen levels by eating low protein foods. Low protein healthy foods include:
- Healthy fats: coconut oil, nuts and avocados.
- Fruits: bananas, berries and apples.
- Cereals: pasta, rice and oatmeal.
- Vegetables: broccoli, bell peppers and green vegetables.
Treatments for abnormal BUN levels?
Doctors do not usually prescribe medicines to remedy abnormal blood urea nitrogen (BUN) levels.
A note from Big Man Lab
After your body breaks down protein, a waste product is produced in the liver called urea nitrogen. Health problems can sometimes appear when your blood contains too little or too much urea nitrogen. You should see your doctor if you have symptoms of low or high blood urea nitrogen levels. Your health care provider may in order to see how well your kidneys are working and to suggest appropriate remedy, order a BUN (blood urea nitrogen) test.
