Deck 27: Heme Metabolism

Question 1

A newborn is found to have persistent jaundice that does not resolve spontaneously even 4 weeks after birth.Repeated blood tests show an unconjugated hyperbilirubinemia, with bilirubin levels of 8 to 15 mg/dL on different occasions.Finally, treatment with phenobarbital succeeds in bringing the bilirubin level to less than 4 mg/dL.This disorder is most likely:

A)Dubin-Johnson syndrome.
B)Gilbert syndrome.
C)Crigler-Najjar syndrome type II.
D)Rotor syndrome.
E)Megaloblastic anemia.

Answer 1

Crigler-Najjar syndrome type II.

Question 2

One test that can detect many types of porphyria is the determination of urinary:

A)Dihydroorotic acid.
B)Urobilinogen.
C)Stercobilin.
D)Biliverdin.
E)Porphobilinogen.

Answer 2

Porphobilinogen.

Question 3

Very small quantities of urobilinogen are normally found in the urine.In the clinical laboratory, urinary urobilinogen is useful for differentiating between types of jaundice.Specifically, you have to expect the following levels in patients with acute hepatitis (but without cholestasis), severe hemolysis, and cholestasis (biliary obstruction):

A)Hemolysis: reduced; hepatitis: reduced; cholestasis: elevated.
B)Hemolysis: absent; hepatitis: elevated; cholestasis: absent.
C)Hemolysis: elevated; hepatitis: elevated; cholestasis: elevated.
D)Hemolysis: elevated; hepatitis: elevated; cholestasis: absent.
E)Hemolysis: elevated; hepatitis: reduced; cholestasis: reduced.

Answer 3

Hemolysis: elevated; hepatitis: elevated; cholestasis: absent.