All About Liver Function Tests

Overview

Liver function tests are a group of tests performed to diagnose or evaluate the overall function of the liver and to monitor for any kind of liver abnormalities.

Numerous tests can be performed on the liver. Some tests may reveal different aspects of liver function.

When is Liver Function Test performed?

This test is performed when a person is at a risk for developing liver damage because of:

1. Taking medicines that can harm the liver
2. Excessive alcohol consumption
3. Having a family history of liver diseases
4. Being overweight while having diabetes or hypertension

The test is also performed in individuals with symptoms of liver diseases such as:

1. Weakness or fatigue
2. Loss of appetite
3. Abdominal pain or swelling
4. Jaundice
5. Passing dark-coloured urine or light-coloured stool

Types of Liver Function Tests

Common tests to check for liver abnormalities include:

1. Alkaline phosphatase (ALP): This test is used
2. Alanine transaminase (ALT)
3. Aspartate aminotransferase (AST)
4. Bilirubin
5. Albumin

While the ALP test can be used to measure or evaluate the bile duct system of the liver, both AST and ALT tests measure enzymes released by the liver in response to a disease or damage. While the bilirubin test measures how well the liver is disposing bilirubin, the albumin test measures how well the liver creates albumin..

Having abnormal results on any of the above liver function tests usually requires a follow up to conclude the cause of the abnormalities. Even mildly raised results can be linked to liver disease.

Talk to a doctor about the results of your liver function test to know what they could mean for you.

How is a liver function test performed?

Your blood will be drawn in a hospital or a diagnostic centre. To administer the test:

1. A nurse or a para-medical staff will first clean your skin before the test at the injection site to minimise the possibility of infection due to any microorganisms on the skin
2. An elastic strap is wrapped on the arm, which will help in making your veins visible. Then, a needle is used to draw blood samples from your arm.
3. Some gauze and a bandage is placed over the puncture site after drawing the blood. Then, the blood sample is sent to a laboratory for testing.

When to Avoid Liver Funtion Test?

There is no specific condition when this test should be avoided. Inform your doctor about any medications, prescription or over-the-counter medications, including herbal supplements, that may affect the liver function test results.

How to prepare for Liver Function Test?

For some of the tests included in the panel, it might be required for you to fast overnight with consuming water alone. Follow instructions provided by your doctor. In order to perform Liver Function Test, a blood sample is drawn from a vein in the arm and sent to the laboratory.