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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Hepatitis B Core Ab, IgM

Test Code(s): CORM / XHBCM

CPT Code(s): 86705

Methodology: Chemiluminescent Immunoassay

Days Performed: Mon-Fri, dayshift.

Turnaround Time: Stat: Not available stat.
Routine: Next working day.

Specimen Requirements

Specimen: Blood

Collection Container: Preferred: Red cap with yellow ring (SST)
Also Acceptable: Red top

Collection Volume: Preferred: 3 mL
Pediatrics: 1.5 mL

Sample Analyzed: Serum

Volume Required: Preferred: 1 mL
Pediatrics: 0.5 mL

Specimen Processing: Centrifuge.  If complete barrier is not formed, transfer cell-free serum to plastic vial.  Refrigerate.

Specimen Transport: Transport specimen to UWHC Core Laboratory (B4/220) within 60 minutes of collection. Transport with coolant pack if coming from outreach location.

Stability: Ambient: 8 hours
Refrigerated: 7 days
Frozen: freeze if sample will not be assayed within 48 hours


Reference Interval:  Nonreactive



Interpretive Guidelines:


Nonreactive: The presence of antibody to hepatitis B core without IgM indicates past infection with hepatitis B.  Anti-hepatitis B core antibody persists for life.


Equivocal:  Recollect if clinically warranted. 


Reactive:  The presence of IgM antibody to hepatitis B core represents acute infection or acute resolving infection.  Anti-HBc IgM generally persists for up to 6 months if the disease resolves.  In patients who have chronic HBV infection, IgM anti-HBc can persist at low levels during viral replication.  Persons with exacerbations of chronic infection can test positive for IgM anti-HBc.      


Interpretation of Hepatitis B Test Result.pdf 

Test Limitations:

Results may be affected if patient has developed heterophillic antibodies due to exposure to animal based protein products.


The assay performance characteristics have not been established for immunocompromised or immunosuppressed patients, newborns, infants or children, cord blood, neonatal specimens, cadaver specimens, heat inactivated specimens and body fluids other than serum.

Additional Information:

This method is approved for diagnostic testing only.  It is not approved for screening tissue donors that fall under FDA's HCT/P requirements.

Anti-HBc AHBCM hep b ahbc

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