Description

What is this test?

Liver function test is a set of blood tests used to monitor the working of the liver or to screen the liver damage or inflammation. This test helps in diagnosing a liver disease or liver condition. This test also measures the amount of certain enzymes and proteins in the blood. Some of these tests are helpful in estimating the performance of the liver functions like producing proteins, clearing of waste products in blood like bilirubin and some tests are used to measure the amount of enzymes that are produced by the liver which may indicate damage of the liver.

What is liver and it's functions?

The liver is the vital organ present in your body. It is reddish brown in color which may weigh around 3 pounds. The gallbladder is attached at the bottom of the liver along with pancreas and intestines. Liver and these organs help in digestion, absorption, and processing of food. The liver filters the blood which comes from the digestive tract and transports the filtered blood to the remaining parts of the body. The liver also makes proteins which are used for blood clotting and also albumin an important protein in blood serum which transports fatty acids and steroids. It also absorbs and metabolizes bilirubin. Bilirubin is formed as the result of the breakdown of hemoglobin, liver stores the iron released by hemoglobin and utilizes it to make the next generation of red blood cells. It also helps in fat metabolization by breaking down fats and making them digest easily. Liver stores carbohydrates which can be broken down into glucose and later used as energy when needed. It also filters blood from waste products, including alcohol and other drugs. Vitamin A, D, E, K, and B12 are stored by the liver.

Importance of liver function test:

Liver function tests are mainly used to estimate the severity of a disease like alcoholic hepatitis or viral hepatitis, to detect liver infections like hepatitis or scarring of a liver (cirrhosis), to know the effectiveness of a treatment, to detect the side effects of certain medicines. Liver function tests include the following tests: Albumin- Albumin is a protein made by the liver. Measuring the amount of albumin shows if the liver is producing the required quantity of albumin. Total protein- Measures the amount of proteins made by the liver. Albumin and globulin are the important proteins made by the liver. Total bilirubin- Bilirubin is a yellow pigment in the blood. It passes through the liver and gets excreted. Elevated levels may show liver damage or liver disease. Aspartate transaminase (AST)- It is an enzyme which metabolizes alanine a type of amino acid. Elevated levels may show liver damage or liver disease. Alanine transaminase (ALT)- It is an enzyme which metabolizes protein. Elevated levels indicate liver damage or liver disease. Alkaline phosphatase (ALP)- It is an enzyme present in liver, bones and bile ducts. High levels of this show liver damage or liver disease. Gamma-glutamyltransferase (GGT)- It is an enzyme in the liver used for estimating bile duct problems.

Why this test is performed?

This test may be recommended to you if you experience certain symptoms like dark colored urine, diarrhea, nausea and vomiting, loss of appetite, yellow color skin and eyes, light colored or bloody stools, swollen abdomen, fluid accumulation in abdomen (ascites), pain in abdomen, tiredness, weight loss or weight gain, etc. This test may also be recommended if you have a history of viral hepatitis or a family history of liver disease, drinking too much alcohol or on a medication which may damage your liver function.

Preparation