Bilirubin and fractions (direct, total and indirect)

This test combines total bilirubin and its fractions, helping distinguish patterns of bile pigment production, processing and excretion. The distribution of direct and indirect fractions is used when investigating jaundice, liver disease and disorders of red blood cell breakdown. This item lists total, direct and indirect bilirubin; how the indirect fraction is obtained should be checked with the laboratory.

Predominance of a particular fraction guides further investigation but does not replace diagnosis of the cause of a change and assessment of other measurements. The doctor assesses the result together with symptoms, medical history and other investigations. The reference values of the individual laboratory are used for comparison, and changes over time are considered during follow-up.

• Assess total bilirubin and the distribution of its fractions.
• Clarify the pattern of impaired bilirubin metabolism.