Jaundice + LFTs Flashcards
what blood tests are taken to measure liver function
Bilirubin Albumin Prothrombin Time (PT) ALP (alkaline phosphatase) AST + ALT GGT
which LFTs measure the livers synthetic function
Bilirubin, Albumin, PT
which LFTs demonstrate hepatocellular damage
AST + ALT
which LFT is significantly raised in cholestasis
ALP
what is bilirubin
a normal breakdown product of Haem metabolism
where is bilirubin conjugated
the liver
- then excreted via bile into GI tract
what happens to bilirubin that is excreted into GI tract
majority egested in faeces as urobilinogen + stercobilin (colours faeces)
roughly 10% is reaborbed into bloodstream + excreted by kidneys
what is jaundice
the yellow discolouration of the sclera / skin as a result of hyperbilirubinaemia
what are the three types of jaundice
pre-hepatic
hepatic
post-hepatic
what is the mechanism of pre-hepatic jaundice
excessive red blood cell breakdown
LFT results pre-hepatic jaundice
isolated rise in bilirubin
- bilirubin is unconjugated as has not undergone conjugation in liver
- normal AST, ALT, ALP
causes of pre-hepatic jaundice
Gilberts syndrome
Haemolytic anaemia
what is Gilberts syndrome
autosomal recessive condition causing defective bilirubin conjugation
- deficiency of UDP glucuronosyltransferase
- jaundice during illness, fasting, exercise
LFTs in Gilberts syndrome
isolated rise unconjugated bilirubin
what is the mechanism of hepatic jaundice
dysfunction of hepatic cells