Overview Hyperbilirubinemia leading to yellowing of skin and eyes classified by ratio of conjugated bilirubin:total bilirubin CB < 20% login to view 3 more bullets CB 20-50% login to view 1 more bullet CB > 50% login to view 4 more bullets Pathophysiology hepatocytes convert unconjugated (indirect) bilirubin into conjugated (direct) bilirubin performed by glucuronyl transferase enzyme to make bilirubin water soluble login to view 1 more bullet bilirubin is not toxic at moderate levels high increases can result in kernicterus and death deposition of bilirubin in the brain Types hemolytic destruction of RBCs than conjugation/excretion system can handle can result from login to view 1 more bullet obstructive intrahepatic or bile duct block does not allow body to excrete bilirubin can result from login to view 3 more bullets hepatocellular damage to liver (i.e. hepatitis, cirrhosis) ↓ ability of conjugation/excretion system to handle normal bilirubin load Jaundice TypeHyper bilirubinemiaUrine BilirubinUrine UrobilinogenHepatocellularConjugated or unconjugated↑Normal/↓ObstructiveConjugated↑↓HemolyticUnconjugatedAbsent↑