Liver disease and hyperlipidaemia Flashcards
what are the functions of the liver?
digestive/secretory/metabolic
detoxification/excretion
synthetic (clotting factors/proteins)
storage (vitamins/minerals)
what are some possible signs of liver disease?
jaundice
weight loss/inappetence
depression/CNS signs
skin lesions
haemorrhage
colic
oedema
diarrhoea
bilateral laryngeal paralysis
what is jaundice?
retention of bilirubin (mainly unconjugated)
what are some differentials for jaundice?
anorexia
haemolysis
liver failure
what are some possible CNS signs that can present with liver disease?
quiet/dull
yawning
progression to somnolence, blindness, head pressing, compulsive walking
what are some skin lesions associated with liver disease?
photosensitisation
pruritus
coronitis
why does liver disease causes hepatic photosensitisation?
phylloerythrin accumulation as the liver doesn’t remove it, this is activated by UV light
what is the cause of pruritus associated with liver disease?
accumulation of bile acids
why may liver disease cause haemorrhage?
decreased production of clotting factors
why can liver disease cause colic?
hepatitis leads to stretching of the liver which is painful
why is laryngeal paralysis one of the first neuropathies seen with liver disease cases?
recurrent laryngeal nerve is very long so any toxins which effect axons will cause damage to this one first
what do liver enzyme tests tell us about?
liver damage (released when liver cells are damaged/break open)
what liver enzymes are of biliary origin?
GGT and ALP
what liver enzymes of of hepatocellular origin?
SDH, GLDH, AST, LDH
which liver enzymes are liver specific?
GGT, SDH, GLDH
what is a non-liver source of AST?
muscle
which enzyme is the most sensitive indicator of liver damage?
GGT
what form of liver disease can raised GGT and ALP indicate?
biliary
what form of liver disease does raised AST, GLDH and LDH indicate?
hepatocellular
how does the degree of increase of liver enzymes correlate with the prognosis?
very poorly correlated
why does there need to be significant liver damage before function is impaired?
has a 70% reserve capacity and the ability to regenerate
what is the most useful test in horses to assess liver function?
bile acids
what is the function of bile acids?
absorb lipids and lipid soluble vitamins
excretion of cholesterol