Direct Bilirubin

Direct (Conjugated) Bilirubin measures the form of bilirubin that has been conjugated (made water-soluble) by the liver. Elevated direct bilirubin (>0.3-0.4 mg/dL or >20-25% of total) specifically points towards problems with bilirubin excretion from the liver or bile ducts, such as hepatitis, cirrhosis, gallstones, or bile duct obstruction, rather than problems with RBC breakdown or initial liver uptake/conjugation.