Dubin-Johnson Syndrome
Joseph Misdraji, MD
Key Facts
Etiology/Pathogenesis
Mutations in cMOAT/MRP2 gene causes impaired biliary transport of conjugated bilirubin
Clinical Issues
Chronic or intermittent jaundice, precipitated by pregnancy or oral contraceptives
Isolated conjugated hyperbilirubinemia
Shift in urine coproporphyrin isomers from isomer III to isomer I
Macroscopic Features
Grossly pigmented liver
Microscopic Pathology
Coarse granular pigment in centrilobular hepatocytes
Ancillary Tests
Periodic acid-Schiff with diastase digestion and Fontana-Masson stains highlight pigment
 Gross photograph of liver core biopsies embedded in the paraffin block show dark regions  corresponding to the pigment within centrilobular hepatocytes. |
 Hematoxylin & eosin section shows coarse granular pigment deposition in centrilobular hepatocytes. |
TERMINOLOGY
Definitions
Defect in hepatocellular secretion of conjugated bilirubin
ETIOLOGY/PATHOGENESIS
Genetic Disorder
Autosomal recessive
Mutations in cMOAT/MRP2/ABCC2 gene, which codes for ATP-dependent organic anion transport localized to canalicular membrane
Results in impaired biliary canalicular transport of organic anions including conjugated bilirubin
Impaired glutathione excretion reduces bile saltindependent bile flow
CLINICAL ISSUES
