Direct Bilirubin
Disclaimer: Information on this page is for educational purposes. Consult a physician to interpret your test results. Health Vault helps track biomarker trends but does not replace medical advice.
What This Test Measures
Direct (conjugated) bilirubin is processed by the liver for biliary excretion. Elevation is typical of cholestasis and obstructive jaundice.
With mechanical obstruction (stones, tumors), direct bilirubin often exceeds 50% of total.
This marker helps distinguish post-hepatic from pre-hepatic and hepatic causes of hyperbilirubinemia.
Normal Ranges
| Group | Reference Range |
|---|---|
| Men | 0–0.3 mg/dL (0–5.1 µmol/L) |
| Women | 0–0.3 mg/dL |
| Children | 0–0.3 mg/dL |
Reference ranges may vary by laboratory and assay method.
Causes of High Levels
- Obstructive jaundice (stones, strictures, tumors)
- Primary biliary cholangitis
- Drug-induced cholestasis
- Sepsis
- Dubin-Johnson syndrome
Causes of Low Levels
- Isolated decrease is rare
Test Preparation
- Fasting preferred
- Report right upper quadrant pain and stool color changes
Related Biomarkers
| Biomarker | Relationship |
|---|---|
| Total Bilirubin | Total bilirubin |
| Alkaline Phosphatase | Cholestasis marker |
| Gamma-Glutamyl Transferase (GGT) | Biliary duct injury |
FAQ
How often should I take this test?
Immediately if jaundice or cholangitis suspected.
What should I do if my result is abnormal?
Elevation with pain, fever, and dark urine — emergency evaluation for cholangitis.
Last updated: June 2026