Liver being the largest discrete organ has some of the major functions in the body. The liver helps in the metabolism, synthesis, storage, excretion and the detoxification of various harmful substances These important and different functions mean that a single test can’t give enough information to fully assess the health of the liver. Therefore we need many different tests to evaluate fully the health of the liver.
Liver function tests (LFT’s) therefore become essential to determine the status of liver health. Various liver-specific enzymes and proteins that are tested in your blood are:
- Alpha-1 antitrypsin
- Alkaline phosphatase (ALP)
- Alanine aminotransferase (ALT)
- Aspartate aminotransferase (AST)
- Gamma-glutamyl transpeptidase (GGT)
- 5′ nucleotidase
- Prothrombin time, also expressed as an international normalized ratio (INR)
- Serum bilirubin
- Urine bilirubin
Depending on the laboratory, reference ranges for LFTs tend to vary. Normal reference ranges vary between males and females and may be higher for those with higher body mass index.
- Alanine transaminase -> 0 to 45 IU/L
- Aspartate transaminase -> 0 to 35 IU/L
- Alkaline phosphatase -> 30 to 120 IU/L
- Gamma-glutamyltransferase -> 0 to 30 IU/L
- Bilirubin -> 2 to 17 micromoles/L
- Prothrombin time ->10.9 to 12.5 seconds
- Albumin -> 40 to 60 g/L
The results are then interpreted by your doctor. These are interpreted either individually or together, to find out the possible cause of your illness.