Veterinary Handbook

ALT (Alanine aminotransferase)

Species: Dog, Cat

Specimen: Plasma or serum

Container: EDTA, heparin or red top tube

Collection protocol: Fasted sample preferred.

Special handling/shipping requirements: Standard

General information about the disease: Liver (hepatocyte) injury

General information about when this test is indicated:

An indicator of damage to liver cells. Also found in kidney and in cardiac and skeletal muscle. Present in hepatocyte cytosol with higher concentrations in periportal cells. Magnitude in serum correlates to number of cells affected but cannot be used to assess prognosis. Some animals with severe liver disease may have normal serum ALT due to lack of viable hepatocytes. Half-life in dogs controversial but levels usually rise rapidly within 24-48 hours and resolve over 2-3 weeks if no further injury, but pattern is highly variable. Increases seen with Phenobarbital treatment. Major differentials: Circulatory disturbances (including anaemia), hepatotoxicity, infection, inflammation, endocrine associated hepatopathy, neoplasia, drug effect.

Comparison with other related tests: More liver specific than AST