Bilirubin Metabolism

Question 1

Lysis of erythrocytes occur in which organ

Answer 1

Spleen

Question 2

Which molecule is converted to bilirubin in histiocytes

Answer 2

Heme

Question 3

Which molecule helps to transport bilirubin through the blood

Answer 3

Albumin

Question 4

What s bilirubin conjugated with to make it more soluble

Answer 4

Glucuronic acid

Question 5

Conjugated bilirubin is secreted into what substance so it can go into the intestines

Answer 5

Bile

Question 6

What is stercobilin

Answer 6

The converted form of urobilinogen that is excreted as a red brown color in feces

Question 7

What is urobilin

Answer 7

The converted form of urobilinogen that gets excreted as a yellow color in urin

Question 8

Which enzyme breaks down heme

Answer 8

Heme oxygenase

Question 9

Heme oxygenase is responsible for the conversion of what

Answer 9

Heme to biliverdin

Question 10

Biliverdin reductase is responsible for the conversion of what

Answer 10

Biliverdin to Bilirubin

Question 11

UDP- glucuronyl transferase is responsible for the conversion of what

Answer 11

1. Bilirubin to Bilirubin monoglucuronide

2. Bilirubin monoglucuronide to Bilirubin diglucuronide

Question 12

What is the last product of bilirubin metabolism before it is converted to urobilirubin and excreted

Answer 12

Bilirubin diglucuronide

Question 13

What is hyperbilirubinemia

Answer 13

Elevated plasma bilirubin levels

Question 14

What are the three types of jaundice

Answer 14

Pre-hapatic, Hepatic and Post-hepatic

Question 15

Which test can help differentiate between conjugated and unconjugated bilirubin

Answer 15

van den Bergh’s test

Question 16

For unconjugated bilirubin, a direct van den Bergh’s test would show what

Answer 16

A purple color immediately

Question 17

For unconjugated bilirubin, an indirect van den Bergh’s test would show what

Answer 17

no immediate color change after addition of alcohol

Question 18

For unconjugated and conjugated bilirubin, an indirect and direct van den Bergh’s test would show what

Answer 18

Purple color that intensifies after addition of alcohol

Question 19

What is kernicterus

Answer 19

Irreversible brain damage

Question 20

Deficiency in UDP-gucuronyl transferase causes which disease

Answer 20

Criggler-Najar Syndrome (Type 1 more severe than type 2)

Question 21

Which pathology associated with bilirubin metabolism is usually asymptomatic (only slight jaundice)

Answer 21

Gilbert’s Disease

Question 22

Gilbert’s disease occurs as a result of

Answer 22

Defective uptake of bilirubin by liver

Question 23

What is the pathology behind hemolytic crisis

Answer 23

More bilirubin in the blood than albumin can transport

Question 24

What is the pathology behind hemolytic (Rh) disease of newborns

Answer 24

The mom is Rh -ve, while the baby is Rh +ve. Can lead to the fetus having kernictus

Question 25

Apart from hemolytic disease of the newborn, what are two other hemlytic crises

Answer 25

Sickle cell crisis and G6PDH deficiency

Question 26

What is physiological jaundice common in most newborns

Answer 26

There is destruction of RBCs and the enzyme foe metabolism have not fully developed yet

Question 27

What is the pathology behind alcoholic jaundice

Answer 27

Increased breakdown of hemoglobin, so liver is unable to break it all down, which causes an increase in unconjugated bilirubin

Question 28

What is the pathology behind obstructive jaundice

Answer 28

Increase in conjugated bilirubin due to occlusion of bile duct

Question 29

Three causes of obstructive jaundice

Answer 29

Gall stones, pancreatic head cancer, bile duct cancer

Question 30

What generally causes pre-hepatic jaundice

Answer 30

Increased hemolysis

Question 31

What generally causes hepatic jaundice

Answer 31

Liver damage which results in decreased bilirubin excretion

Question 32

What generally causes post-hepatic jaundice

Answer 32

Bile duct obstruction which leads to bilirubin excretion