Liver Disease

Common Liver Function Tests

What are some of the most common liver function tests?

A series of special blood tests can often determine whether or not the liver is functioning properly. These tests can also distinguish between acute and chronic liver disorders and between hepatitis and cholestasis.

The most commonly performed blood tests include:

Serum Bilirubin Test - Elevated levels of bilirubin often indicate an obstruction of bile flow or a defect in the processing of bile by the liver. Bilirubin is produced by the liver and is excreted in the bile.
Serum Albumin Test - Below-normal levels of albumin, a protein made by the liver, are associated with many chronic liver disorders.
Serum Alkaline Phosphatase Test - Elevated levels of alkaline phosphatase, an enzyme found in the bile, usually indicate an obstruction of bile flow, liver injury, or certain cancers.
Serum Aminotransferases (transaminases) - This enzyme is released from damaged liver cells.
Prothrombin Time (PTT) Test - This test measures the time it takes for blood to clot. Blood clotting requires vitamin K and a protein made by the liver. Liver cell damage and bile flow obstruction can both interfere with proper blood clotting.
Alanine Transaminase (ALT) Test - This enzyme is released from damaged liver cells.
Aspartate Transaminase (AST) Test - This enzyme is released from damaged liver, heart, muscle, or brain cells.
Gamma-glutamyl Transpeptidase Test - This enzyme is produced by the liver, pancreas, and kidneys and released into the blood when these organs are injured.
Lactic Dehydrogenase Test - This enzyme is released when organs such as the liver, heart, lung, or brain are injured.
5-Nucleotidase Test - This enzyme is released by the liver when the liver is injured due to bile duct obstruction or impaired bile flow.
Alpha-fetoprotein Test - This protein is produced by the fetal liver and testes, indicating hepatitis or cancer.
Mitochondrial Antibodies Test - The presence of these antibodies can indicate primary biliary cirrhosis, chronic active hepatitis, and certain other autoimmune disorders.

This page was last updated on: February 6, 2008.

For patient inquiries, call 1-800-492-5538 or click here to make an appointment.