Hepatitis B Core Antibody IgM

Message

Performed in the Chemistry Laboratory x5820
10.2018

Test Code

HBCM

CPT Codes
86705

Preferred Specimen

Plasma from a green top (PST) tube

Minimum Volume

1 mL

Transport Container

Green Top (PST) tube

Transport Temperature

Room temperature

Specimen Stability

2 - 8 ^oC: 7 days

Methodology
Chemiluminescent Microparticle Immunoassay

Setup Schedule

This assay is performed Monday through Friday

Reference Range

Results are reported as "NON-REACTIVE", "EQUIVOCAL", or "REACTIVE".

Clinical Significance

IgM antibodies against the hepatitis B virus core antigen (Anti-HBc IgM) are a marker of recent infection and appear with the onset of symptoms. Anti-HBc IgM is gradually replaced by Anti-HBc IgG, but can persist up to 32 weeks after infection. Two additional tests for hepatitis B virus surface antigen (HBsAg (HBSAG)) and for antibodies against the hepatitis B virus core antigen of all heavy chain types (total Anti-HBc (HBCOR)) can help to interpret clinical situations in which Anti-HBc IgM are non-reactive. Anti-HBc IgM are non-reactive in uninfected individuals (HBsAg (HBSAG) non-reactive AND total Anti-HBc (HBCOR) non-reactive) and remote infections. Remote infections need to be distinguished into remote cleared infections (HBsAg (HBSAG) non-reactive AND total Anti-HBc (HBCOR) reactive) and chronic active infections (HBsAg (HBSAG) confirmed positive AND total Anti-HBc (HBCOR) reactive).

Anti-HBc IgM are not induced by vaccination and do not convey immunity against infection. Use a separate test for antibodies against hepatitis B virus surface antigen (Anti-HBsAg (HBSAB)) to determine successful vaccination.

Typical patterns of Hepatitis B Virus related serum markers

Marker	No exposure *	Acute infection	Chronic infection **	Resolved infection	Vaccination
HBsAg (HBSAG)	NON-REACTIVE	CONFIRMED POSITIVE	CONFIRMED POSITIVE	NON-REACTIVE	NON-REACTIVE
Anti-HBs (HBSAB)	NON-REACTIVE	NON-REACTIVE	NON-REACTIVE	REACTIVE	REACTIVE
Anti-HBc IgM (HBCM)	NON-REACTIVE	REACTIVE	NON-REACTIVE	NON-REACTIVE	NON-REACTIVE
total Anti-HBc (HBCOR)	NON-REACTIVE	REACTIVE	REACTIVE	REACTIVE	NON-REACTIVE

* consider recent exposure
** in chronic Infection HBs Ag levels may wane and Anti-HBc IgM may recur in flares

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.