Jaundice

Question 1

Why is there pale stool and dark urine in obstructive jaundice?

Answer 1

Urobilinogen in the GIT is converted to stercibilin ( brown) and excreted.
In obstructive jaundice the bile is not emptying into the GIT.
Accumulation of conjugated bilirubin in the blood -> water soluble so is excreted in the urine.

Question 2

Pre hepatic causes of jaundice

Answer 2

The prehepatic causes of jaundice are due to excess Bilirubin production

• haemolytic anaemia
• ineffective erythropoiesis eg. thalassaemia

Question 3

Post hepatic causes of jaundice

Answer 3

The post hepatic causes of jaundice aka obstructive causes

• Stones in biliary tree
• Cancer
• in the head of the pancreas
• hepatoma
• ampullary carcinoma
• cholangiocarcinoma
• PSC
• PBC
• pseudocyst causing obstruction
• pancreatitis

Question 4

What drugs can cause jaundice?

Answer 4

Anti malarial can cause haemolysi s

Paracetamol OD or hepatotoxic agents can cause hepatitis

Question 5

What investigations would show a pre-hepatic jaundice?

Answer 5

- haemolytic anaemia
> elevated unconjugated BR
> elevated LDH
> low Hb
> low haptoglobin 

no Bilirubinin the urine, some urobilingoen

could do Coombes test - agglutination => AIHA

Question 6

What investigations would show a hepatic jaundice?

Answer 6

Bilirubin and urobilinogen in the urine
elevated conj BR
elevated AST and ALT, and GGT and ALP
low albumin and increased PT

FBC -

Question 7

Investigations showing post hepatic jaundice?

Answer 7

elevated bilirubin and no urobilogen in the urine

blood with
elevated conj BR, elevated ALP and GGT

US showing dilation >6mm of the CBD
ERCP or MRCP