Jaundice
Haemoglobin splits and globin and heme release.
Heme consists of four pyrrole rings.
Heme ring open and release pyrrole rings.
Pyrrole will under go several reaction and bilirubin form.
Unconjugated bilirubin enter to hepatic cells.
Conjugate
80% - bilirubin glucuronide.
10% - bilirubin sulfate.
10% - other substances.
Form biliverdin.
Further reduced to bilirubin.
First form is unconjugated/free bilirubin.
Release from macrophage to plasma.
Not soluble and bind to protein.
Conjugated bilirubin turn to urobilinogen by bacteria in the intestine.
Excrete via stool.
Urobilinogen can be reabsorbed to blood.
5% excrete via urine.
Urobilinogen turn to urobilin by oxidization when expose to air.
Stercobilinogen turn to stercobilin by oxidization when expose to air.
Jaundice
Excess bilirubin in the extracellular fluid.
Haemolysis
increase unconjugated bilirubin in plasma.
Urobilinogen increase
Intrahepatic cholestasis
acute and chronic liver diseases including cirrhosis
increase in both type bilirubins
Jaundice
Obstructive jaundice
Stones, tumour in the biliary tract, pancreatic head tumour.
Increase conjugated bilirubin.
No/less urobilinogen
Stool became clay colour.
Significant amount of conjugated bilirubin in urine.