Bilirubin Metabolism + Jaundice

Question 1

Prehepatic: hemolytic jaundice

Answer 1

clinic: high levels of indirect bilirubin seen in plasma (direct also high but not seen)
- massive RBC lysis overwhelms liver capacity to make bilirubin diglucouronide

Question 2

hepatic: neonatal jaundice

Answer 2

clinically: increased indirect bilirubin levels

low UDP-GT at birth
low GST-B

Question 3

post-hepatic: obstructive jaundice

Answer 3

clinically: pale feces due to absence of stercobolin; both direct and indirect bilirubin in blood

obstruction of bile duct prevents BGA (conjugated bilirubin) to intestines

get backflow into circulation

Question 4

Hepatic: hepatocellular jaundice

Answer 4

damage to liver cells that can affect liver uptake of bilirubin and the conjugation of bilirubin to BGA
(ex: MRP2 dysfxn; alcoholic)