Liver Disease CPC Lecture Flashcards
What is the reference range for bilirubin?
5-17 micromol/L
What is ALT? AST? GGT?
- Alanine Aminotransferase
- Aspartate Aminotransferase
- Gamma-glutamyltransferase
These are enzymes. Many more could be measured.
Explain the anatomy of liver lobules.
Sinusoids are lined by epithelial cells.
Hepatic portal vein to central vein is where everything is removed
Portal veins go to gut
Central vein goes to IVC
Describe this picture.
Hepatocytes are born proximal to the sinusoid and die distal to it.
What does the portal triad consist of?
- Portal vein
- Hepatic artery
- Bile duct
What might you see on US in someone with high bilirubin?
Tumour of head of pancreas
Gall stones
What other bloods would you do in someone with high bilirubin?
Bloods - amylase (pancreatic function), repeat LFTs, FBC
Viral screen - hepatitis
How are causes of high bilirubin categorised?(3)
Pre-hepatic e.g. haemolysis
Hepatic -
Post-hepatic - obstructive jaundice
Why are neonates commonly jaundiced? How are they treated?
Unconjugated bilirubin - lack of light so giive phototherapy?
What condition causes high fasting bilirubin?
Gilbert’s
How is Gilbert’s inherited?
Recessive
What is the cause of jaundice in paediatric cases?
- It usually is, but the bilirubin should be unconjugated as the cause is usually liver immaturity coupled with a fall in the haemoglobin early in life.
- If it doesn’t settle, other rare causes should be looked for including hypothyroidism, other causes of haemolysis (including a Coombes test or DAT), and the unconjugated bilirubin will be useful.
What reaction is used to measure serum bilirubin (conjugated)?
The van den Bergh reaction
The addition of methanol causes a complete reaction, which measures total bilirubin (conjugated plus unconjugated); the difference measures unconjugated bilirubin (an indirect reaction).
Describe the pathophysiology of Gilberts.
- UDP glucuronyl transferase activity reduced to 30%
- Unconjugated bilirubin tightly albumin bound and does NOT enter urine.
- Worsened by fasting
- Effects of phenobarb : reduces levels
Which marker is most representative of liver function?
- Prothrombin time (liver makes clotting factors) - if PT rises by one second per hour then you might need to refer pt for a transplant (normal PT - 11-13.5)
- Albumin is also useful
- Bilirubin
Other tests are enzymes and not truly tests of liver function (rather, damage).
How is paracetamol overdose treated?
N-acyetyl-cysteine