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Test ID: Hepatitis B Core Antibody IgM
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Hepatitis B Core Antibody IgM
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Detection of Hepatitis B Core IgM Antibody in Blood
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Useful For
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Involves the detection of HBV specific antigens and/or antibodies to identify different phases of the HBV infection to determine whether a patient has acute or chronic HBV infection, is susceptible to infection, or is immune to HBV as a result of prior infection or vaccination. In addition, some of these HBV markers are routinely used in patient and donor screening.
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Method name and description
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Electrochemiluminescence immunoassay (ECLIA): μ-Capture test 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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HBV is consists of an external envelope (HBsAg) and an inner core. The hepatitis B core antigen (HBcAg) is a highly immunogenic nucleocapside protein. During an infection with HBV, antibodies to HBcAg appear shortly after the onset of HBV infection and can usually be detected in serum soon after the appearance of HBsAg. Free HBcAg or core particles are not detectable in serum. Anti‑HBcIgM antibodies are one of the first serologic markers of HBV infection and usually persist for up to 6 months, being then replaced by anti‑HBcIgG antibodies. High titers of anti‑HBcIgM are detected during acute hepatitis B infection while low titers can be detected during chronic hepatitis B infection (CHB), and moderately high titers can occur in cases of CHB associated with viral replication and inflammatory activity. Tests to detect anti‑HBcIgM antibodies are used, in conjunction with HBsAg determinations, to identify acute HBV infections. However, what occasionally appears to be an acute hepatitis B can occur in undiagnosed CHB carriers and additional tests are required to differentiate between chronic and acute infection.
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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 20 – 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 < 1.0
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Non-reactive
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Negative for anti‑HBcIgM
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COI
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COI ≥ 1.0
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Reactive
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Positive for anti‑HBcIgM
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*COI = cutoff index
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Factors affecting test performance and result interpretation
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As with many µ‑capture assays an interference with unspecific human IgM is observed. Increasing amounts of unspecific human IgM may lead to a decrease in the recovery of positive samples with the Elecsys Anti‑HBc IgM assay
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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