Kidney Function Test with eGFR

The Blood Urea Nitrogen test measures the levels of urea nitrogen in the blood. Blood urea is a waste product that is formed in the liver when you eat food and the protein is metabolized into amino acids. This process leads to the production of ammonia that is further converted into urea. Both ammonia and urea are nitrogenous compounds. Your liver releases urea into the blood which is then carried out to the kidneys. In the kidneys, urea is filtered from the blood and flushed out of the body via urine. This is a continuous process, so a small amount of urea nitrogen always remains in the blood.

In the case of a kidney or liver disease, there is a change in the amount of urea present in the blood. If your liver produces urea in an increased amount or if there is any problem in kidney functioning, there might be difficulty in filtering out the waste products from the blood, which can result in increased urea levels in the blood.

The Serum Creatinine test measures the level of creatinine in the blood. Creatinine is a byproduct of muscles’ wear and tear during energy production. The kidneys remove it from the body by filtering it from the blood and releasing it into the urine. Therefore, blood creatinine levels indicate how well the kidneys are functioning in filtering and removing waste products from the blood. Generally, higher creatinine levels in the blood may indicate reduced kidney function, while lower levels may suggest decreased muscle mass.

The Serum Electrolytes test measures three important electrolytes in the body: sodium, potassium, and chloride. Electrolytes are electrically charged minerals that move fluid in and out of the cells. They transport the nutrients into the cells and flush out the waste products. They also help maintain water balance and pH levels by keeping the acids and bases in your blood balanced. Hence, the body must maintain an optimal balance of fluids and electrolytes for proper functioning.

This further contains

• Potassium
• Chloride
• Sodium

The BUN/Creatinine Ratio test helps compare the levels of blood urea nitrogen to that of creatinine in your body. Urea is a waste product that is formed in the liver when you eat protein, which is then metabolized into amino acids. This process leads to the production of ammonia that is further converted into urea. Later, the urea is passed out of your body through the urine. On the other hand, creatinine is a byproduct produced by muscles during energy production. Therefore, the more muscle you have, the more creatinine your body produces. The kidneys remove both the urea and creatinine via urine, and this test determines how well your kidneys are functioning.

The Blood Urea test measures the level of urea in the blood. Urea is a byproduct of protein metabolism. Proteins you consume in your diet are digested and converted into amino acids, which are then utilized by the body. This metabolic process produces a toxic byproduct known as ammonia. Ammonia is then rapidly converted into urea by your liver. Urea is comparatively less toxic than ammonia and is transported to the kidneys via the blood. The kidneys then filter it out through the urine. This process continues and the body keeps producing and eliminating urea, maintaining its low and steady levels in the blood.

An Uric Acid test determines the level of uric acid in your body. Uric acid is a nitrogenous compound produced by the metabolic breakdown of purine. Purines are present as nitrogenous bases in the DNA and are also found in food like red meat and seafood.

Most uric acid dissolves in the blood and goes into your kidneys. From there, it passes through your body via the urine. Decreased elimination of uric acid is often a result of impaired kidney function due to kidney disease. In many cases, the exact cause of excess uric acid is unknown. Doctors seldom need to test for low levels of uric acid.