Bilirubin, total

What it measures

Total bilirubin measures the yellow pigment formed when haemoglobin is broken down. It is used to investigate jaundice, liver disease, haemolysis and neonatal hyperbilirubinaemia.

Specimen and preparation

• Specimen: Serum or lithium-heparin plasma
• Tube: Gold top
• Preparation: Protect the sample from light; avoid haemolysis and lipaemia.

Reference range

Reference ranges differ between laboratories, methods and populations. Always use the range printed on your own lab report.

Causes of high values

• Haemolysis (unconjugated)
• Gilbert syndrome
• Hepatitis and cirrhosis
• Biliary obstruction
• Neonatal physiological jaundice
• Drug-induced liver injury

Causes of low values

• Not clinically significant

Method

Diazo colorimetric method or vanadate oxidation; direct spectrophotometry in neonates

Good to know

Fractionate into direct and indirect bilirubin to separate pre-hepatic from hepatic and post-hepatic causes. Neonatal action thresholds depend on age in hours.

Related tests