Bilirubin, Fractionated

Includes Direct Bilirubin, Indirect Bilirubin (calculated), Total Bilirubin

Preferred Specimen(s) 1 mL serum

Transport Container Amber plastic screw-cap vial or foil-wrapped plastic screw-cap vial

Transport Temperature

  • Ambient 5 days,
  • Refrigerated 2 weeks

Reject Criteria

  • Gross hemolysis
  • Anticoagulants other than heparin

Methodology Spectrophotometry (SP)

Clinical Significance Measurement of the levels of bilirubin is used in thediagnosis and treatment of liver, hemolytic, hematologic, and metabolic disorders, including hepatitis and gall bladder obstructive disease. The assessment of direct bilirubin is helpful in the differentiation of hepatic disorders. The increase in total bilirubin associated with obstructive jaundice is primarily due to the direct (conjugated) fraction. Both direct and indirect bilirubin are increased in the serum with hepatitis. In the newborn patient with hemolytic jaundice and neonatal jaundice, the increase in the total bilirubin is primarily due to the indirect (unconjugated) bilirubin fraction. This jaundice may be caused by Rh, ABO, or other blood group incompatibilities, by hepatic immaturity, or by hereditary defects in bilirubin conjugation.