Jaundice

Question 1

What are the 3 overall causes of jaundice?

Answer 1

Pre-hepatic/haemolysis (unconjugated)
Hepatic/hepatocellular (associated with signs of liver failure)
Post-hepatic/obstructive (pale stools, dark urine, itch)

Question 2

What causes the yellowing of the skin and sclera in jaundice?

Answer 2

Increase in plasma bilirubin ≥ 50-60 micro mol/L

Question 3

What can cause unconjugated hyperbilirubinemia?

Answer 3

(As unconjugated bilirubin is water-insoluble, it does not enter urine, resulting in unconjugated hyperbilirubinaemia)

Overproduction - due to haemolysis, ineffective erythropoiesis
Impaired hepatic uptake - due to drugs (e.g. paracetamol, rifampicin), ischaemic hepatitis
Impaired conjugation
Neonatal jaundice

Question 4

How can conjugated hyperbilirubinemia present?

Answer 4

DARK urine
PALE stools

(As conjugated bilirubin is water-soluble, it is excreted in urine, making it dark. Less conjugated bilirubin enters the gut and the faeces become pale. When severe, it can be associated with an intractable pruritus/itch which is best treated by relief of the obstruction)

Question 5

What can cause conjugated hyperbilirubinemia?

Answer 5

Hepatocellular dysfunction - due to: viral hepatitis, drug induced, alcohol, cirrhosis, haemochromatosis, Wilson’s disease

Impaired hepatic excretion (cholestasis/obstruction) - due to primary biliary cholangitis, primary sclerosing cholangitis, gallstones, cancer of head of pancreas, cholagiocarcinoma

Question 6

What can cause obstructive jaundice?

Answer 6

Common causes:

• Gallstones (causes biliary colic pain, dull pain in RUQ)
• Primary biliary cholangitis
• Carcinoma of head of pancreas (painless)

Uncommon

• Primary sclerosing cholangitis
• Cholangiocarcinoma (suspected if gallbladder can be palpated)

Question 7

What LFTs results are seen in obstructive jaundice?

Answer 7

ALP (alkaline phosphatase) is raised (to a greater extent than ALT & AST)

Question 8

What can cause hepatocellular jaundice?

Answer 8

Common causes:

• Alcoholic hepatitis or cirrhosis
• Viral hepatitis
• Drug induced (e.g. paracetamol overdose)
• Non-alcoholic fatty liver disease

Uncommon:

• Autoimmune liver disease
• Haemochromatosis
• Wilson’s disease

Question 9

What LFTs are seen in hepatocellular jaundice?

Answer 9

ALT and AST (transaminases) are raised (to a greater extent than ALP)

Question 10

What are important risk factors to ask?

Answer 10

Alcohol intake
Drug use (including non-prescription drugs)
Travel
Blood transfusions
Tattoos
Unprotected sex

Question 11

What is looked at in LFTs?

Answer 11

Clotting factors, esp. prothrombin time or INR
Albumin - useful to monitor degree of liver damage and prognosis
Liver enzymes:
- Transaminases - ALT, AST
- Alkaline phosphatase (ALP)

Question 12

What can cause haemolytic jaundice?

Answer 12

Increased RBC breakdown

• can be due to RBC abnormality e.g. sickle cell
• incompatible blood transfusion
• drug reaction
• hypersplenism

Question 13

What colour are stools in haemolytic jaundice?

Answer 13

DARK poo

as unconjugated bilirubin cannot be excreted in urine

Question 14

What investigations may be done for jaundice?

Answer 14

Urinalysis
FBC
Clotting film
LFTs
Albumin
Ultrasound - are bile ducts dilated? indicates mass causing blockage
ERCP - endoscope
MRCP - MRI of ducts