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Hepatitis B Core Antibody, Qualitative (Serum/Plasma)

Published: August 9, 2026Updated: August 16, 2026

This test detects antibodies to the hepatitis B core antigen, which may indicate past or current infection with hepatitis B virus (HBV).

Quick summary

["This test helps determine if you’ve been exposed to hepatitis B virus."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
21005-4
Short code
HBV core Ab Ser Donr IA-aCnc
Synonyms
HBV core Ab Ser Donr IA-aCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
ia
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What Does This Test Measure?

The test looks for the presence of antibodies against the hepatitis B core antigen. These antibodies are produced by your immune system in response to HBV infection. If antibodies are found, it suggests your body has either fought off the virus or is still responding to it.

Why Might You Need This Test?

Your healthcare provider may order this test if you have risk factors for hepatitis B (e.g., exposure to infected blood, travel to regions with high HBV prevalence, or certain medical conditions). It can also be used during screening or follow-up for chronic hepatitis B.

What Does a Positive Result Mean?

A positive result means your immune system has detected HBV core antigens, which could mean you’ve been infected at some point. This does not always indicate an active infection but may indicate immunity or past exposure.

What Does a Negative Result Mean?

A negative result suggests you either have never been exposed to HBV or your body has cleared the virus without producing detectable antibodies. However, this does not guarantee you are completely protected.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: This test is critical for diagnosing past or potential hepatitis B infection. It helps guide decisions about vaccination, monitoring, or preventive measures, especially in high-risk individuals.

Short name

Hep B Core Antibody (Qualitative)

Frequently asked questions

How is this test performed?
A small blood sample is drawn from your arm. The sample is tested in a lab using an immunoassay method to detect antibodies against the hepatitis B core antigen.
What are the typical reference ranges?
This test is qualitative, meaning it only provides a positive or negative result. There are no numeric reference ranges provided.
Can this test be used to diagnose active hepatitis B?
No, this test alone cannot diagnose active hepatitis B. It may be used alongside other tests (like hepatitis B surface antibody or viral load tests) for a full assessment.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy