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Difference between conjugated and unconjugated hyperbilirubinemia

Following are the difference between conjugated and unconjugated hyperbilirubinemia
                                               Unconjugated                                  conjugated                 
Water solubility                      0                                                        +
Affinity for lipids                      +                                                       0               
Renal excretion                         0                                                       +
Van den Bergh reaction     Indirect                                              Direct

Fractions of normal bilirubin
Normal serum bilirubin level is 0.3-1.0 mg/dl.
Conjugated fraction is 0.1-0.3 mg/dl and
Unconjugated fraction is 0.2-0.7 mg/dl.
What are the conditions which produce predominantly conjugated and unconjugated hyperbilirubinemia?
Conjugated hyperbilirubinaemia is said to occur with > 50% conjugated fraction of bilirubin is conjugated
Causes of conjugated hyperbilirubinemia
  • Viral or drug-induced hepatitis.
  • Drug-induced cholestasis.
  • Cholestatic jaundice of pregnancy.
  • Cirrhosis of liver.
  • Dubin-Johnson syndrome.
  • Rotor syndrome.
  • Secondary carcinoma of liver.
Causes of unconjugated hyperbilirubinemia
Unconjugated hyperbitirubinaemia is said to occur when the unconjugated fraction is > 80%
Causes of conjugated hyperbilirubinemia
  • Haemolysis.
  • Ineffective erythropoiesis.
  • Prolonged fasting (<300 cal/day).
  • Gilbert's syndrome and rarely Crigler-NaJ|ar syndrome
  • Neonatal jaundice.