T3 Paracetamol overdose & liver cirrhosis Flashcards
functions of liver
- carbo. metabolism
- fat metabolism
- proteinn metabolism
- bilurubin metabolism
- vitamin sotrage (A, D, B12, Fe)
- cogulation factors
- detoxification
idiosyncratic hepatotoxins
rare & unpredictable reactions
intrinsic hepatotoxins
high doses –> liver injury (paracetamol)
major pathways of paracetamol metabolism
- sulphate conjugation
- glucuronide conjugation
minor pathway of paracetamol metabolism
P450 enzymes: CYP2E1; CYP1A2
what is the toxic metabolite of paracetamol
NAPQI
what is the size of the toxic dose of paracetamol and what molecule is depleted when taking that dose
- 2gm+
- Glutathione
how can liver necrosis/failure be detected in lab tests?
+++ AST, ALT
what cuases jaundice in liver failure
- no bilirubin metabolism
- mostly conjugated hyperbilirubinaemia
what causes hepatic encephalopathy (coma) in liver failure
- no detoxification of nitrogenous compounds
- circulation of excitatory AAs
what causes bleeding in liver failure
no clotting factors made (2, 7, 9, 10)
what causes renal failure in liver failure
low glomerular filtration
drugs used to treat paracetamol overdose
- activated charcoal
- N-acetyl cysteine –> L-cysteine –> glutathione
most reliable method to assess fibrosis
biopsy
causes of chronic liver disease
- infection
- autoimmunity
- alcohol
- obesity
- biliary diseases
- genetic diseases
- drug induced
