Lab test
Hepatitis B Surface Antigen Lab Test
Hepatitis B Surface Antigen Lab Test can be ordered without a referral, and this guide covers what to expect. This blood test looks for Hepatitis B surface antigen, an early sign of Hepatitis B infection. It can help detect both recent and long-term infections.
What this test is
The Hepatitis B Surface Antigen test detects a protein found on the surface of the Hepatitis B virus. Its presence in the blood is usually the first indicator of an active Hepatitis B infection.
What it measures
- Hepatitis B Surface Antigen (HBsAg) — indicates the presence of Hepatitis B virus
What the test involves
This test requires a standard blood draw from a vein in your arm. A healthcare professional will collect the sample and send it to a laboratory for analysis.
Why it is often ordered
A clinician may order this test to screen for Hepatitis B infection or to diagnose symptoms of acute or chronic Hepatitis B. It is also used to monitor the effectiveness of Hepatitis B vaccination or treatment.
Preparation
No special preparation is typically needed for this test. Please follow any specific instructions provided by the laboratory where you will have your blood drawn.
How results are reported
Results are usually available within a few business days and will indicate whether the Hepatitis B surface antigen was detected. Reference ranges, which define normal and abnormal levels, can vary between laboratories.
Before you go
- Turnaround time
- Specific preparation instructions
- How results are delivered
FAQ
Frequently asked questions
What does a positive Hepatitis B Surface Antigen test mean?
A positive result means the Hepatitis B virus is likely present in your body. This could indicate a current infection, either acute (recent) or chronic (long-term).
Can this test detect past Hepatitis B infections?
This specific test primarily detects active Hepatitis B infection. Other Hepatitis B tests are available to determine if you have had a past infection or are immune from vaccination.
How soon after exposure can this test detect Hepatitis B?
Hepatitis B surface antigen can typically be detected in the blood about 2 to 4 weeks after exposure, though this can vary.
What are the next steps if my test is positive?
If your test is positive, your healthcare provider will discuss the results with you and recommend appropriate follow-up care. This may include further testing or treatment options.
Related
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Locations
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