Liver disease Flashcards
What are 5 causes of high bilirubin?
- haemolysis
- gallstones
- cholangitis
- sickle cell
- alcoholic liver disease
What is in the portal triad?
- Bile duct
- Branch of hepatic artery and portal vein
What happens in first pass metabolism?
- Oxygen from hepatic artery
- Blood gunge from digestive system from portal vein
- Hepatocytes filter
- Clean stuff in central vein
- Waste products go the other way and end up in bile duct
Where does the central vein go?
to heart and IVC
Where does the central vein go?
to heart and IVC
How do you think about high bilirubin causes?
- pre-hepatic
- hepatic disease
- post-hepatic
What are post-hepatic causes of high bilirubbin?
- obstructive jaundice
1. gallstones (painful)
2. pancreatic cancer (painless)
What are pre-hepatic causes of high bilirubin?
- unconjugated bilirubin
- haemolysis
What reaction measures serum bilirubin via fractionation?
Van de Bergh reaction
What does the direct reaction measure?
conjugated bilirubin
What does the indirect reaction measure?
unconjugated bilirubin
How does the Van den bergh reaction work?
addition of methanol causes a complete reaction, which measures total bilirubin (conjugated plus unconjugated)
What sort of jaundice could be normal?
peadiatric jaundice
In paediatric jaundice what type of bilirubin should be high and why?
unconjugated as the cause is usually liver immaturity coupled with fall in haemoglobin early in life
What should you do if the peadiatric jaundice does not setlle?
look for:
- hypothyroidism
- other causes of haemolysis (Coombes test or DAT)
- unconjugated bilirubin will be useful
How do you treat paediatric jaundice?
phototherapy
How does phototherapy work?
converts bilirubin into two other compounds: lumirubin and photobilirubin which are isomers that do not need conjugation for excretion
Which LFTs will be high in obstructive jaundice?
alk phos
If all the LFTs are normal but fasting bilirubin is high what might this suggest?
gilberts syndrome (very common)
How is Gilbert’s syndrome inherited?
- Recessive
- 50% carry gene
What is the pathophysiology of Gilbert’s syndrome?
- UDP glucuronyl transferase activity reduced to 30%
2. Unconjugated bilirubin tightly albumin bound and does NOT enter urine (so not high bilirubin urine) - but high plasma
What test is the most representative of liver function?
Prothrombin time (if bad bad outcome)
How is the function of the liver tested?
- Albumin
- Clotting factors (PT, PTTK)
- Bilirubin
- Other tests are “enzymes” not truly tests of liver function
What does it mean if AST and ALT is super high?
hepatocyte damage
If alk phos is high but not super high what does this mean?
excludes obstructive jaundice
How does HepA work?
get once - no carrier disease
How does HepB work?
- some carriers
- start making HBe antigen and HBs antigen and measured in blood
- then start to make antibiodies
What does it mean if there are just surface antibodies (Anti-HBs)?
vaccinated
What does it mean is they have all three antibodies (Anti-HBc, Anti-HBs, Anti HBe)?
must have been infected with live virus at some point
Which antibodies will a carrier of HepB never make?
surface antigen (anti-HBs)
What are the defining histological features of alcoholic hepatitis?
- liver cell damage
- inflammation
- fibrosis (use a stain)
What are the associated histological features of alcoholic hepatitis?
- fatty change
2. megamitochondria
What is NASH?
- non-alcoholic steato-hepatitis
- history is that don’t drink alcohol
What is the treatment of alcoholic hepatitis?
- supportive
- stop alcohol
- nutrition
- vitamins (esp B1 and thiamine)
- occasionally steroids
What does vitamin def gives you beri beri?
B1
What does vitamin def gives you rickets?
vitD
What does vitamin def gives you scurvy?
vitC
What does vitamin def gives you perincious anaemia?
B12
What does vitamin def gives you pellargra?
B3
What does vitamin def gives you neural tube defects?
folic acid
