Bilirubin (Direct & Indirect)
Everything you need to know about Bilirubin (Direct & Indirect) levels, including what normal ranges look like and what abnormal results might indicate.
Standard Reference Range
Unit: mg/dLReference ranges may vary slightly between laboratories. Always consult your doctor for interpretation.
What is Bilirubin?
Bilirubin is a yellow pigment created when old red blood cells break down. It circulates as indirect (unconjugated) bilirubin, then the liver converts it to direct (conjugated) bilirubin so it can be excreted in bile.
Key Takeaway
Patterns of indirect vs direct bilirubin help distinguish hemolysis, liver cell injury, and bile duct blockage.
Why is this test performed?
- Evaluate jaundice (yellowing skin/eyes)
- Screen liver function (part of CMP/LFT panel)
- Detect bile duct obstruction or gallstones
- Check hemolysis in newborns or adults
- Monitor known liver disease
Interpreting Your Results
Predominantly Indirect (Unconjugated) Elevation
- Hemolysis or large bruises
- Gilbert syndrome (common, benign)
- Ineffective blood cell production (B12/folate deficiency)
Predominantly Direct (Conjugated) Elevation
- Bile duct obstruction (stones, tumors, strictures)
- Cholestatic medications (e.g., some antibiotics, steroids)
- Hepatitis or cirrhosis impairing bile flow
Mixed Elevation
- Advanced liver disease
- Sepsis-related cholestasis
Low Levels
Not clinically significant; very low values are typically considered normal.
Related Tests
- ALT/AST: Gauge liver cell injury
- ALP/GGT: Rise with bile duct blockage
- Albumin/Total Protein: Reflect the liver’s synthetic function
Decode your Total and Direct Bilirubin Results
Upload your PDF report to WellAlly. AI will visualize your trends and provide personalized health insights instantly.