INHERITED DISORDERS OF BILIRUBIN METABOLISM

Question 1

• Bilirubin Transport Deficit (cannot be transported to hepatocytes)

Answer 1

GILBERT’S SYNDROME

Question 2

Characterized by impaired cellular uptake of bilirubin due to genetic mutation in UGT1A1 gene (chromosome #2)

Answer 2

GILBERT’S SYNDROME

Question 3

Affected individuals may have no symptoms but may have mild icterus and predisposed acetaminophen toxicity.

Answer 3

GILBERT’S SYNDROME

Question 4

GILBERT’S SYNDROME findings:
Indirect Bilirubin:

Answer 4

Indirect Bilirubin: 1.5-3.0 mg/dL (↑)

Question 5

Conjugation deficit (UDGPT problem)

Answer 5

CRIGLER-NAJJAR SYNDROME

Question 6

Chronic non-hemolytic unconjugated hyperbilirubinemia

Answer 6

CRIGLER-NAJJAR SYNDROME

Question 7

CRIGLER-NAJJAR SYNDROME lab result

Answer 7

elevated Indirect Bilirubin

Question 8

CRIGLER-NAJJAR SYNDROME treatment

Answer 8

Phototherapy (because bilirubin is photosensitive)

Question 9

Complete UDGPT deficiency

Answer 9

CRIGLER-NAJJAR SYNDROME Type I

Question 10

CRIGLER-NAJJAR SYNDROME Type I lab result
o Indirect bilirubin:
o Direct bilirubin:

Answer 10

o Indirect bilirubin: > 25 mg/dl
o Direct bilirubin: none

Question 11

CRIGLER-NAJJAR SYNDROME Type I symptoms

Answer 11

kernicterus, colorless bile

Question 12

Partial UDGPT deficiency

Answer 12

CRIGLER-NAJJAR SYNDROME Type II

Question 13

CRIGLER-NAJJAR SYNDROME TREATMENT

Answer 13

PHOTOTHERAPY

Question 14

CRIGLER-NAJJAR SYNDROME Type II lab results
o Indirect bilirubin: 5-20 mg/dl
o Direct bilirubin: Small amount

Answer 14

o Indirect bilirubin: 5-20 mg/dl
o Direct bilirubin: Small amount

Question 15

Familial form of unconjugated hyperbilirubinemia caused by a circulating inhibitor of bilirubin conjugation

Answer 15

LUCEY-DRISCOLL SYNDROME

Question 16

LUCEY-DRISCOLL SYNDROME lab findings
* Indirect bilirubin:

Answer 16

• Indirect bilirubin: increased (2-3 weeks of life)

Question 17

Bilirubin excretion Deficit (conjugated hyperbilirubinemia)

Answer 17

DUBIN-JOHNSON SYNDROME

Question 18

Defective excretion of direct bilirubin into the canaliculi caused by hepatocyte membrane defect.

Answer 18

DUBIN-JOHNSON SYNDROME

Question 19

Characterized of an intense dark pigmentation of the liver due to accumulation of lipofuscin pigment (black liver).

Answer 19

DUBIN-JOHNSON SYNDROME

Question 20

Similar with Dubin-Johnson Syndrome without the “black liver”

Answer 20

ROTOR SYNDROME

Question 21

Rotor syndrome Laboratory findings:
o _______ in direct bilirubin and total bilirubin
o Delta Bilirubin:

Answer 21

o Elevation in direct bilirubin and total bilirubin
o Delta Bilirubin: Increased