Liver disease Flashcards
What are the clinical signs associated with congenital disease?
Seizures, head pressing, ataxia, depression, circling, blindness
What are the clinical signs associated with acquired disease?
Hepatic encephalopathy, jaundice, PUPD, v+, d+, ascites, weight loss
What are the causes of secondary hepatopathies?
Heart failure, seizure, sx, shock, anaemia, sepsis, GI dz, corticosteroids, phenobarbitone, hypothyroidism, hyperthyroidism, Addisons, Cushings, diabetes
What are the indications for biopsy?
In primary disease of unknown aetiology. W/o a biopsy a definitive dx cannot be made. always give vit K prior to biopsy. Contraindicated in animals with coagulopathy. Trucut/FNA.
What is the composition of ascitic fluid?
Transudate - modified transudate
How does bilirubin act as a marker of liver damage?
Causes jaundice
Prehepatic - haemolysis (low PCV)
Hepatic - intrahepatic liver disease (inflammation or fibrosis) causing occlusion of the bile ducts
Posthepatic - bile duct/gall bladder obstruction (pancreatitis, extra-hepatic biliary obstruction)
What are the indicators of liver damage?
Enzymes (ALT, AST, ALPp, GGT) and bilirubin
What are the indicators of liver function?
Ammonia, albumin, glucose, bile acids
Why are bile acids used as a marker for disease?
Dx pre-hepatic jaundice. In hepatic and post-hepatic disease bile acid levels increase prior to jaundice so is not a useful measurement.
Describe the BAST
- starve animal for 12hrs, take a blood
- feed a fatty meal to induce bile acid production
- take another sample after 2hrs
If pre > post could mean bile acids were released in anticipation of food/lab/error/delayed gastric emptying
Why do bile acids increase?
Due to liver failure, inability to uptake them from circulation. Overwhelmed/too much produced.
Why is ammonia used as a marker for liver function?
Generated in the GIT and normally cleared in the liver.
Increase suggests the liver is not functioning properly as is unable to detoxify it. Could indicate function failure or PSS.
Why is albumin used as a marker for liver function?
Albumin is produced by the liver.
Hypoalbuminaemia occurs when more than 66% of liver function is lost. So a small decrease can be significant.
Ascites occurs when albumin is
Why is glucose used as a marker for liver function?
It is a ddx for hepatic encephalpathy.
Hypo is uncommon in dogs but can be due to shunts/severe acute liver failure, hyper is common in cats and is usually due to stress.
What other additional tests could be carried out?
Haematology - non-specific changes, mild non-regenerative anaemia and thrombocytopenia. PSS = microcytic hypochromic anaemia
Urinalysis - PD = low USG. Ammonium urate crystals can indicate PSS
Coagulation - liver produces all clotting factors except VIII, increased clotting times if > 70% factor depletion
What are the indications for Colchicine use?
Mod-marked fibrosis on biopsy. Antithrombotic. SE = bone marrow suppression, anorexia, d+
What are the indications for corticosteroid (Prednisolone) use?
Anti-inflammatory, anti-fibrotic, immunomodulatory.
Inflammation of unknown aetiology, chronic hepatitis, cholangitis in cats.
When might Prednisolone be contraindicated?
Hepatic encephalopathy (catabolic, causes increased ammonia), portal hypertension/PSS, gastric ulceration, diabetic cats
What is the MA and indications for using S-adenosylmethionine?
Glutathione precursor and contains vit E.
Stabilises membranes, anti-inflammatory and anti-fibrotic
Acute toxic hepatopathies
What are the indications for using vitamin E?
Anti-oxidant and anti-fibrotic
Chronic hepatopathies in dogs
What is the MA and indications for using ursodeocycholic acid?
Synthetic hyrophillic bile acid.
Promotes bile flow, reduces hydrophobic bile salt production, anti-apoptotic effects on neurones, hepatocytes, enterocytes and cardiomyocytes, immunomodulatory.
Synergistic with SAM-e
Hepatic jaundice
What are the indications for n-acetylcysteine?
Increases hepatic blood flow
Any acute hepatopathy
What are the indications for Silymarin?
Anti-fibrotic, anti-inflammatry, Anti-oxidant
beneficial effects are unclear
What are the indications for vit K?
Fat soluble vitamin, requires bile acids to be absorbed.
Activates factor VII
Hepatic and post-hepatic jaundice
Give prior to every biopsy, even if PT is normal.
