Blood Urea Nitrogen BUN Test

BUN is tested to check kidney function for diagnosis of kidney disease and to assess progression of disease. This tests is often ordered along with serum creatinine.
It may also be done as part of complete metabolic panel to diagnose metabolic disorders.

Blood urea test measures the concentration of urea and nitrogen in the blood.

A: The BUN Urea Nitrogen Serum test measures urea nitrogen levels in the blood. Urea nitrogen is produced by the body to break down proteins. It comprises two compounds: urea and nitrogen.

The blood sample is taken from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a  little sting when the needle goes in or out. This usually takes less than five minutes.

High BUN levels may be due to renal and pre-renal causes. 
Pre-renal causes include congestive heart failure, severe dehydration, burns, shock, GI bleeding, high protein diet or due to certain medications. 
Renal causes include glomerulonephritis, polycystic kidney disease, obstructive uropathies
Low BUN levels may at times occur due to liver diseases, malnutrition or lack of protein in the diet.

Suppose the results of the BUN Urea Nitrogen Serum test are present. In that case, it indicates that the nitrogen levels in the blood are elevated. This may be caused by kidney, liver, or metabolic problems. If the results are absent, it indicates that the nutrients normally present in the blood are not being adequately absorbed

 Patients do not need to take any special preparation for the BUN Urea Nitrogen Serum test. It is usually performed as part of a routine medical checkup. However, it is advised that patients do not drink alcohol for 24 hours before the test nor have any meal for six to eight hours.

Normal BUN Urea Nitrogen Serum levels are typically in the range of 8 to 25 mmol/l.

The BUN Urea Nitrogen Serum test is a test. It measures the amount of nitrogen present in the blood. It helps to evaluate the condition of the liver, kidney, and other organs and diagnose issues related to nutrition and metabolism.

Several other tests are often ordered as part of a comprehensive medical evaluation.

Blood tests:

• Creatinine: The creatinine test measures the levels of a certain protein in your blood produced by muscle tissue. It’s used to evaluate kidney function. It also helps detect kidney problems.

• Electrolytes: This test detects balance levels of key minerals in the body, like sodium, potassium, chloride, and bicarbonate. Electrolytes are essential for proper health. They are regulated by the kidneys.

• Uric Acid: This test measures the amount of uric acid in the blood. High uric acid levels can indicate kidney or liver problems or gout.

Urine tests:

• Urinalysis: This important exam helps detect changes in urine colour and blood, proteins, and other components of urine.

• Urine Protein: This test looks for the presence of protein in the urine. This can be an indicator of kidney damage.

• Urinary Creatinine: This test calculates the glomerular filtration rate (GFR). It measures how well the kidneys filter waste from the blood.

Blood Urea Nitrogen

• BUN

The BUN test detects the amount of urea nitrogen in the blood, which helps assess kidney function. It indicates how well the kidneys are filtering waste products from the blood.

BUN test reports indicate the level of urea nitrogen in the blood. Normal levels typically range between 7 and 20 mg/dL but can vary slightly depending on age, sex, and the laboratory. Elevated levels may suggest kidney dysfunction, while low levels could indicate other conditions such as liver disease, overhydration, or a low-protein diet.

If the BUN test reports are positive (i.e., elevated), it may indicate impaired kidney function or other conditions such as dehydration, a high-protein diet, or certain medications. Further tests, such as creatinine levels and other kidney function tests, may be ordered to confirm the diagnosis.

The benefits of a BUN blood test include early detection of kidney disease, monitoring of kidney function over time, evaluation of the effectiveness of treatments for kidney problems, and identification of potential kidney damage from medications or other conditions.

Two symptoms that may indicate high BUN levels include fatigue and muscle cramps.

To reduce high BUN levels, you can eat less protein in your diet, stop protein supplements, drink plenty of fluids to avoid dehydration, manage underlying conditions such as hypertension or diabetes, and avoid medications that can affect kidney function.

The BUN test is generally safe and involves minimal risk. The main risk is the potential for bruising or infection at the blood draw site, which is rare.

The BUN test helps in diagnosing and monitoring kidney diseases, such as chronic kidney disease (CKD) and acute kidney injury (AKI). It can also indicate other conditions that affect kidney function, such as diabetes, high blood pressure, and heart disease.

Yes, certain medications can affect BUN test results. These include steroids, antibiotics, and other medications that can impact kidney function or protein metabolism.

No, fasting is not required before taking the BUN test. However, it's advised to inform your healthcare provider about the medications, herbs, vitamins, and supplements you are taking, as they may impact the test results.

Several factors can affect BUN test results, including a high-protein diet, dehydration, burns, certain medications, liver disease, overhydration, pregnancy, and ageing.

The BUN test reports are usually available within 4 hours after the blood sample is taken, depending on the laboratory and the specific tests ordered.