ALP and GGT are proteins that are also made in the liver cells. ALP and GGT are released if the liver is unable to get rid of toxins such as bile acids. GGT levels can go very high and the levels may not tell you how quickly the liver is being injured. However, if you have a problem of bile flow, the ALP probably tells you how bad the problem is.

ALP protein structureGGT protein structure

The red ribbon-like structure on the left is what ALP might look like and the green ribbon-like structure on the right is what the GGT protein might look like.

 

Learning points

ALP goes up when disease slows bile flow, such as Primary Biliary Cirrhosis and Primary Sclerosing Cholangitis, stones in the bile duct, etc.

Exceptions:


GGT can go up because of drugs and toxins, such as alcohol, anti-seizure medicines, and others

ALP can go up with other conditions not related to bile flow:


ALP can go up in cirrhosis, no matter what the cause
Deposits of a form of immune response in the liver called "granulomas"
Cancers spreading to the liver from lung, breast, etc.
Proteins called "amyloid" depositing in the liver