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Test ID: Hepatitis B Core Antibody
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Hepatitis B Core Antibody
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Detection of Hepatitis B Core Antibody in Blood
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Useful For
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Determination of anti‑HBc in association with other hepatitis B tests permits the diagnosis and monitoring of HBV infections. In the absence of other hepatitis B markers (HBsAg-negative persons), anti‑HBc may be the only indication of an existing HBV infection.
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Method name and description
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Electrochemiluminescence immunoassay (ECLIA): Competetion principle
Measurement of antigen or antibody based on the change in electrochemiluminescence (ECL) signal before and after immunoreaction. Results are determined automatically by the software by comparing the electrochemiluminescence signal obtained from the reaction product of the sample with the signal of the cutoff value previously obtained by calibration.
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Clinical information
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The hepatitis B virus (HBV) consists of an external envelope (HBsAg) and an inner core (HBcAg). The hepatitis core antigen comprises 183‑185 amino acids. During an infection with HBV, antibodies to HBcAg are generally produced, which often persist for life.
Anti-HBc appears shortly after the onset of HBV infection and can usually be detected in serum soon after the appearance of HBsAg. Anti‑HBc persists in persons who have recovered from HBV infection and inactive carriers. Therefore, they are an indicator of existing or past HBV infection. In rare cases, HBV infection can also run its course without the appearance of immunologically detectable anti‑HBc (usually in immunosuppressed patients). Anti‑HBc is not produced after vaccination. Due to the persistence of anti‑HBc following infection with HBV, screening for anti‑HBc can be used to identify previously infected individuals.
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Specimen type / Specimen volume / Specimen container
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Specimen type: Serum, Plasma
Minimum volume of sample: 1 mL
Serum: Plain tube (red or yellow top)
Plasma: Li‑heparin
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Collection instructions / Special Precautions / Timing of collection
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Collect blood by standard venipuncture techniques as per specimen requirements. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.
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Storage and transport instructions
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Storage: 7 days at 15 – 25°C
14 days at 2 – 8°C;
3 months at ‑20 °C (± 5 °C)
Transport: 2-25°C
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Specimen Rejection Criteria
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Grossly hemolyzed, icteric and lipemic samples, wrong collection container, insufficient sample and heat‑inactivated samples.
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Biological reference intervals and clinical decision values
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Analyte/Unit
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Result message
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Result message
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Interpretation/ further steps
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COI*
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COI > 1
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Non-reactive
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Negative for anti‑HBc, no further testing needed
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COI
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COI ≤ 1
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Reactive
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All initially reactive samples must be retested in duplicate using the Elecsys Anti-HBc II assay.
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*COI = cutoff index
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Retest result
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Final result/
interpretation
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Further steps
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One or both of the duplicate retests
have a COI ≤ 1.0
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Repeatedly reactive
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No further testing needed.
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Both of the duplicate retests have a COI > 1.0
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Negative for antiHBc
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No further testing needed.
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Factors affecting test performance and result interpretation
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In rare cases, interference due to extremely high titers of antibodies to immunological components, streptavidin and ruthenium can occur
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Turnaround time / Days and times test performed / Specimen retention time
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Daily (24/7)
Turn-around time:
Routine: One working day
Specimen Retention: 4 days
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