Is a direct bilirubin level of 0.2 cause for concern?

A Direct Bilirubin of 0.2 mg/dL is Not Cause for Concern

A direct bilirubin level of 0.2 mg/dL is well within normal limits and does not suggest cholestatic liver disease, biliary obstruction, or any pathologic hepatobiliary condition in adults. 1

Normal Reference Range

• Direct bilirubin is considered abnormal only when it exceeds 1.0 mg/dL (when total serum bilirubin is at or below 5 mg/dL), according to the American Gastroenterological Association 1, 2
• Your patient's value of 0.2 mg/dL is five times lower than the threshold for abnormality 1
• This level is typically within normal limits and requires no further investigation 1

Clinical Context Matters

While the absolute value is reassuring, interpretation depends on two additional factors:

• Total bilirubin level: The ratio of direct to total bilirubin provides diagnostic information about the type of hyperbilirubinemia present 1, 3
• Patient age and clinical presentation: Neonates have different reference ranges than adults, though your question appears to concern an adult patient 1

When Direct Bilirubin Becomes Clinically Significant

Direct bilirubin warrants investigation in these scenarios:

• Absolute threshold: Direct bilirubin >1.0 mg/dL when total bilirubin ≤5 mg/dL 2
• Percentage threshold: Direct bilirubin >20% of total bilirubin suggests pathologic conditions 3
• Drug-induced liver injury: Direct bilirubin typically >35% of total bilirubin 1, 2
• Cholestatic disease: Direct bilirubin fraction >30% strongly suggests hepatobiliary pathology 3

Important Measurement Considerations

• Laboratory measurements of direct bilirubin can vary between laboratories and methods 1
• Direct bilirubin includes both conjugated bilirubin and delta bilirubin (albumin-bound), which has a half-life of approximately 21 days 1, 2
• Some older laboratory methods can produce falsely elevated direct bilirubin values, particularly with certain diazo reagents 4

Bottom Line

At 0.2 mg/dL, this direct bilirubin level requires no action, no further testing, and no clinical concern. 1 This value is completely normal and does not indicate liver dysfunction, biliary obstruction, or any pathologic process requiring investigation.