ALT or alanine aminotransferase is an enzyme that naturally occurs in the blood. The amount of ALT in the blood is measured by a blood test.

ALT Test Overview

This source begins with a simple overview that defines AST. For more information on the test and how it is performed, click the Next>> link at the bottom of the page.

Click here for information on normal ALT values and what abnormal results may indicate.

ALT is tested as part of a routine liver panel, which also includes:

• ALP
• AST (To learn more about how ALT and AST results should be interpreted together, click here.)
• Serum Albumin
• Serum Globulin
• Prothrombin Time
• Serum Ammonia
• Serum Bilirubin

Possible causes include:

• Liver disease
• Cirrhosis
• Leptospirosis

Healthy Liver Function

Understanding the Liver