Conjugated hyperbilirubinemia in seen in
A. Rotors synd.B. Dubin Johnson syndrome
C. Gilbert’s syndrome
D. Breast milk jaundice
E. CrigglerNajjar syndrome
The
Answer is. A. Rotors synd.[Refer Figure # 9]
Crigler-Najjar
syndrome
There
are actually two types of Crigler-Najjar, and both are they different
clinically.
Type
I CN
-
Rare
-
autosomal
recessive disorder
-
Absent
UGT1A1 activity. UGT1A1 is a liver
enzyme that participates in bilirubin processing
-
The
unconjugated bilirubin backs up into
the blood, producing severe jaundice and icterus.
-
Usualy
fatal in the neonatal period unless liver transplant is done
Type
II CN
-
autosomal dominant disorder
-
Some
UGT1A1 activity is seen (the enzyme is only capable of forming
monoglucuronidated bilirubin).
-
Non
fatal, good prognosis.
Gilbert
syndrome
-
Common
disorder, autosomal recessive
-
Decreased
activity of UGT1A1 (but more than Type II Criggler najjar)
-
Unconjugated
hyperbilirubinemia, with no clinical consequence
Dubin-Johnson
syndrome
-
Autosomal
recessive disorder
-
Conjugated
bilirubin in the blood.
-
Caused
by a defect in secretion of bilirubin glucuronides (which is already
conjugated!) across the canalicular membrane (patients are missing a
canalicular protein that transports bilirubin glucuronides into bile).
-
Liver
biopsy: darkly pigmented because of coarse granules within the hepatocyte
cytoplasm.
-
Most
patients are asymptomatic (except for yellow skin)
Rotor
syndrome
-
Autosomal
recessive disorder
-
Conjugated
bilirubin in the blood.
-
Unknown
defect
-
Asymptomatic
(except for mild jaundice)
Must
remember:
1.
CD ROM (Conjugated – Dubin, Rotor) | Use CNG: (Unconjugated – Criggler Najjar, Gilbert)
2.
All
are AR except type II CN
