Jaundice Flashcards
What type of jaundice is seen classically with the following bloods:
Hb 153, Plts 75, WCC 6.4, ALT 90, Alk Phos 132, Bili 40, PT 24
Hepatocellular
A raised ALT, an Alk Phos within the upper limits of normal, with low platelets and high INR, this is most likely to be hepatocellular in nature (most commonly alcoholic liver disease)
A patient is admitted with RUQ pain and blood tests showing a post-hepatic jaundice, the patient otherwise well and stable. What is the most appropriate initial investigation?
US abdomen
What are the bilirubin levels for the jaundice to occur?
Bilirubin levels >50µmol/L
What is the jaundice result of?
High level of bilirubin in the blood
Bilirubin pathway
- Bilirubin is the normal breakdown product from the catabolism of haem (destruction of RBCs)
- bilirubin undergoes conjugation within the liver, making it water-soluble
- It is then excreted via the bile into the GI tract, the majority of which egested in the faeces as urobilinogen
- Around 10% is reabsorbed into the bloodstream and excreted through the kidneys
Jaundice occurs when this pathway is disrupted.
Pre-hepatic jaundice
- what happens in overall?
- what happens to bilirubin?
Pre-hepatic jaundice
- Happens as a result of excessive breakdown of RBCs
- the liver cannot cope with excess bilirubin -> cannot conjugate it all -> unconjugated bilirubin
- unconjugated bilirubin = jaundice
*some bilirubin can manage to be conjugated and to be excreted normally. It’s only an unconjugated bilirubin that remains in the bloodstream and appear as a jaundice
Hepatocellular jaundice
- what happens?
- what picture of jaundice can be seen and why?
Hepatocellular/ intracellular
- liver loses its ability to conjugate bilirubin (due to liver damage/ impairment)
- mixed picture jaundice may occur because, example:
- liver cirrhosis may compress on the hepetic portion of biliary duct -> conjugated bilirubin
- liver damage -> cannot conjugate -> unconjugated bilirubin
Post-hepatic jaundice
- what happens
- type of jaundice
Post-hepatic
- bilirubin cannot be excreted from a biliary tract due to obstruction
- as bilirubin was conjugated by the liver -> conjugated hyperbilirubinaemia
Pre- hepatic causes of jaundice
Name some specific conditions
- *Pre-Hepatic**
- Haemolytic anaemia
- Gilbert’s syndrome or Criggler-Najjar syndrome
Hepatocellular jaundice causes
(specific conditions)
Hepatocellular jaundice
- Alcoholic liver disease
- Viral hepatitis
- Medication
- Hereditary haemochromatosis
- Autoimmune hepatitis
- Primary biliary cirrhosis
- Primary sclerosing cholangitis
- Hepatocellular carcinoma
Post-hepatic jaundice causes
- specific conditions
Post-hepatic jaundice
- Intra-luminal causes, such as gallstones
- Mural causes, such as cholangiocarcinoma, strictures, or drug-induced cholestasis
- Extra-mural causes, such as pancreatic cancer or abdominal masses (e.g. lymphomas)
Colour of urine and type of jaundice
Conjugated bilirubin (as per normal pathway) may be excreted in the urine
- dark, coca-cola urine -> in conjugated, mixed-type jaundice
- normal urine -> in unconjugated
Investigations for jaundice (bloods) + rationale
FBC -> anaemia, raised MCV, thrombocytopaenia - seen in all liver diseases
LFTs-> to look for a degree of jaundice, hepatocellular injury
U&Es
Coagulation studies -> PT may be raised in liver dysfunction (due to impaired synthesis of clotting factors)
LFTs in testing for jaundice
(explain each component of the blood test)
- Bilirubin -> to assess the degree of jaundice
- Albumin -> marker of liver synthesis function
- AST and ALT -> marker of hepatocellular injury
- Alkaline Phosphatase -> raised in a biliary obstruction (or in bone injury)
- Gamma-GT -> raised in biliary obstruction
*Gamma-GT is not a part of standard LFTs - requested separately if ALP is raised
What conditions are the ratios suggesting of:
- AST:ALT ratio of >2
- AST:ALT ratio of around 1
- AST:ALT ratio of >2 -> likely alcohol liver disease
- AST:ALT ratio of around 1 -> likely viral hepatitis