Veterinary Handbook

GDH, GLDH (Glutamate dehydrogenase)

Species: All but most commonly used in large animals (horse, ruminants)

Specimen: Plasma or serum

Container: EDTA, heparin or red top tube

Collection protocol: Fasted sample preferred (in companion animals).

Special handling/shipping requirements: Standard

General information about the disease: Liver (hepatocyte) injury, especially acute.

General information about when this test is indicated:

An indicator of damage to liver cells. Mitochondrial leakage enzyme in cytoplasm. In humans more activity in centrilobular than periportal hepatocytes. More liver specific than AST. Generally, less sensitive than GGT for detecting liver damage in horses but has a better positive predictive value. Magnitude in serum generally correlates to number of cells affected but cannot be used to assess prognosis. Half-life approximately 14 hours in bovine. Increases sometimes 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 and generally, less sensitive than GGT  for detecting liver damage in horses but has a better positive predictive value.