8 Liver and Jaundice

Question 1

In haemolysis, what is formed?

Answer 1

haem: unconjugated bilirubin and iron
Globin: amino acids

Question 2

Is unconjugated bilirubin water soluble?

Answer 2

No, it’s lipophilic

Question 3

Can unconjugated bilirubin be transported in the blood?

Answer 3

yes, only using albumin though

Question 4

How is unconjugated bilirubin conjugated, what effect does this have?

Answer 4

in the liver by adding glucoronic acid, making it more hydrophilic, it is then excreted into the bile

Question 5

What do intestinal bacteria do in the bilirubin cycle?

Answer 5

convert conjugated bilirubin to urobilinogen by removing glucoronic acid, making it lipid soluble

Question 6

What happens to urobilinogen?

Answer 6

10% re-enters the blood, 1/2 of which will re-enter the bile and another 5% will be transported to the kidneys

Question 7

What causes jaundice? (very broadly)

Answer 7

unconjugated bilirubin build-up

Question 8

What might be the cause of pre-hepatic jaundice?

Answer 8

haemolytic anaemia (causing gall stones, dark urine
hepato / splenomegaly)
paroxysmal nocturnal haemgoglobinurea
sickle cell disease

Question 9

What is Gilbert’s syndrome?

Answer 9

a form of pre-hepatic jaundice, where a mutation in the gene for bilirubin UDP–glucuronyl transferase 1 inhibits the conjugation of bilirubin

Question 10

How might viral hepatitis cause hepatic jaundice?

Answer 10

infection of hepatocytes and subsequent immune response can release excess bilirubin into the blood

Question 11

What proportion of jaundices hepatitis C sufferers will show immunity clearance, or be a chronic carrier, what happens to chronic carriers?

Answer 11

10% immunity clearance
90% chronic carrier
cirrhosis many years later

Question 12

What causes post-hepatic jaundice?

Answer 12

obstruction, so gallstones or disease of the ducts

Question 13

how might pancreatic cancer cause pot-hepatic jaundice?

Answer 13

growth obstructs the bottom of the common bile duct