VCP 411: Medicine Section

Hepatic disease and function

HEPATIC DISEASE

• Hepatic disease is difficult to diagnose based on clinical findings alone, laboratory tests are necessary.
• Specific tests are not available to specify the exact nature of the disease. Hence a combination of tests is performed.
• Icterus index-indicates the presence of unconjugated bilirubin.
• Testing for bile acids
• Arginase-cholestasis and hepatacellular necrosis
• GGT
• SDH, GGT, GOT and BSP clearance test – sensitive indicators of hepatocellular injury in cattle.
• Chronic hepatic lesion: horse – leukocytosis, neutrophilia, hypoalbuminaemia, increased alkaline phosphatase, GGT, increased, AST, SDH and total lactate dehydrogenase.

Hepatic function:

• Those which measure the excretory rate of parenterally administered substrates e.g. BSP.
• Those which measure the ability of the liver to remove the substances from the serum detoxify them
• Those which measure the serum levels of the liver enzyme which increase following the hepatic injury.
• Non specific tests which provide some indirect assessment of hepatic function – blood glucose, serum protein, clotting factors, urinalysis.
• Serum hepatic enzymes.
• Sorbitol dehydrogenase – indicator of liver damage – sheep and goat.
• Serum alkaline phosphatase – increase markedly when there is damage to biliary tissue, also increase when there is damage to other tissues – more useful when there is biliary obstruction.
• Aspartate amino transaminase or alanine amino transaminase indicator of liver damage but they are not specific.
• Arginase specific indicator of acute hepatic disease but not for less severe form
• GGT indicate hepato biliary disease.
• Glutamate dehydrogenase in liver damage
• Ornithine carbomyl transferase (OCT) both acute and chronic liver damage.