Reviewed: 13. Juli 2026
HBsAg Hepatitis B Surface Antigen (HBsAg)
Quick Explanation
HBsAg is a component of the hepatitis B virus's outer shell and the most important marker for an acute or chronic hepatitis B infection. A positive result means the virus is actively detectable in the body and should be further evaluated by a doctor.
🔍 Possible Causes
Value too high — possible causes
- ·Acute hepatitis B infection
- ·Chronic hepatitis B infection
This list shows possible causes — not a diagnosis. Only your doctor can correctly interpret your result.
🩺 Questions for Your Doctor
- →Is this an acute or chronic infection?
- →Is treatment or further monitoring necessary?
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Medical Disclaimer
The content on this page is for general information only and does not replace professional medical advice, diagnosis, or treatment. Always consult your doctor or pharmacist for health-related questions. Lab values should always be assessed in the context of your personal medical history.