Liver function tests (LFTs) provide information about the condition of a person’s liver. They measure chemicals in the blood that are made by the liver. Medical problems affecting the liver can change the level of these chemicals, and abnormal results may show there is a problem.

LFTs help diagnose liver disorders and monitor the activity and severity of liver disorders. The tests usually measure:

Alanine transaminase (ALT)

The level of ALT increases when the liver is injured or inflamed.

Asparate aminotransferase (AST)

The level of AST increases when the liver is injured or
inflamed. AST can also be released from heart or other muscle damage.

Gamma-glutamyl transferase (GGT or gamma GT)

A raised level of this enzyme can be from fat in the liver or alcohol use. Some medications also cause the GGT to rise.

Alkaline phosphatase (ALP)

High levels of ALP can occur with other liver diseases (not viral
hepatitis). It can also be elevated if there are bone problems.

Albumin

Albumin is an important protein made by the liver. Albumin production can fall when the liver is damaged and not working very well.

Bilirubin

A high blood level of bilirubin can occur with various liver and bile duct conditions. It can be high when the flow of bile is blocked or if the liver is damaged and not working very well. A high level of bilirubin can cause jaundice (yellow skin and eyes).

Alpha fetoprotein (AFP)

AFP is not part of the usual LFT tests, but at the Hepatitis Foundation we check it as it's a marker for liver cancer. It can also be slightly raised due to active hepatitis B and C.

AFP is normally elevated in pregnant women.

* Normal values and ranges for liver tests are often different for women and men. Please consult a doctor or other health care professional for diagnosis and treatment of medical conditions.

Find out more about Liver Function Tests from bpac nz.