investigation of jaundice Flashcards
definition of acute liver failure
- reversible
- onset of hepatic encephalopathy occurs within 8 weeks of the first onset of illness
definition of chronic liver disease
-usually the result of cirrhosis
what is seen in the histology of the liver with liver disease
- activated stellate cells
- deposition of a scar matrix
- loss of fenestrae
- loss of hepatocyte microvilli
- Kupffer cell activation
adverse prognostic criteria in ALF caused by paracetamol
pH <7.3 HE grade III or IV Cr>300 PT>100 seconds or 2 of 3 above with deterioration or lactate>3.5
adverse prognostic criteria in ALF caused by non paracetamol
Pt>100 seconds or 3 of the following -PT>50 -age <10 or >40 -jaundice to enceph >7 days -bilirubin>300 aetiology not HAV or HBV
ethanol detoxification pathway
ethanol->acetaldehyde- ADH
acetaldehyde-> acetic acid
acetic acid-> co2+h20
methanol detoxification pathway
methanol->formaldehyde ADH
formaldehyde-> formic acid
what do formaldehyde and formic acid cause
blindness
cerebral oedema
metabolic acidosis
ethylene glycol pathyway and what effects on the body does it have
->glycoaldehyde (ADH)-CNS
Glycolic acid-metabolic acid
glyoxylate-lactic acidosis
oxalate- brain and renal damage
treatment for methanol or ethylene glycol poisoning
to give fomepizole competitive inhibitor of ADH
paracetamol pathway in over dose
Bad one
CYP450 forms Nacetylbenzoquinoneimine binds to cells causes hepatotoxicity and nephrotoxicity
-as glutathione is saturated or depleted in chronic alcoholism
what do you give for paracetamol overdose
n-acetylcysteine which is basically glutathione breaks it down into nice products
production of bilirubin pathway
spleen=haemoglobin-> haem-> bilirubin
blood=unconjugated albumin bound bilirubin
liver=conjugated bilirubin
Biliary excretion
Bile-> intestines and faecal excretion (makes it brown)
what conjugates bilirubin
UDP glucuronyl transferase
what changes urobilinogen to sterobilins
bacterial
what is the rate limiting step in bilirubin metabolism
biliary excretion as requires ATP
plasma, urine and faecal findings of bilirubin in health
plasma=unconjugated small amounts
urine=none
faeces=excreted amount
3 types of jaundice
pre-hepatic
hepatic
post-hepatic
lab results for pre-hepatic jaundice
unconjugated hyperbilirubinaemia
no bilirubin in urine
<60 bilirubin
normal LFTs
lab results for hepatic jaundice
mixed hyperbilirbinaemia
bilirubin in urine
<200
increased LFTs- ast and alt
lab results for post-hepatic jaundice
conjugated hyperbilirubinaemia bilirubin in urine pale stools <400 increase LFT: cholestatic
what is kernicterus and treatment
-premature babies may not be able to conjugate bilirubin until UDP glucuronyl transferase produce
-unconjugated
-toxic to brain=kernicterus
treat with phototherapy
gilbert’s syndrome which gene
-syndrome where liver doesn’t break down bilirubin
-mutation in UGTA1 gene
-autosomal dominant
-unconjugated
-don’t need treatment unless severe
more common in males
what is red lysis
over production haemolysis so get unconjugated hyperbilirubinemia
