Hepatitis B Viral Serology

Last updated 03.11.12

 

Index

 

Definition

-  Serology to detect current or past infection with Hepatitis B virus &/or prior immunisation

 

Features

-  Hepatits serology

-  Routine screening in pregnancy as part of antenatal investigations

 

Tests

-  Hepatitis B Surface Antigen (HBs Ag)

-  Hepatitis B Surface Antibody (HBs Ab)

-  Hepatitis B Core Antibody (HBc Ab)

-  Hepatitis B Core Anitbody IgM (HBc Ab IgM)

-  Hepatitis B e Antigen (HBe Ag)

-  Hepatitiis B e Antibody (HBe Ab)

-  Hepatitis B Viral DNA

 

 

Interpretation

-  Vaccination

-  +ve: HBs Ab

-  -ve: everything else = HBs Ag, HBV DNA..

-  Previous Infection

-  +ve: HBs Ab, HBc Ab

-  -ve: HBs Ag, HBc Ab

-  Current Infection 

-  +ve: HBs Ag, HBs Ab, HBc Ab, HBc Ab IgM, HBe Ag

 

Hepatitis B Surface Antigen (HBs Ag)

-  Surface Ag

-  Indicates current infection

-  Does not DDx between acute & chronic

-  Usually first serum marker detectable in acute infection

 

Hepatitis B Surface Antibiody (HBs Ab)

-  Indicates vaccination or past infection

-  > 10 units = immunized

-  Recommended > 40 units

 

Hepatitis B Core Antibody (HBc Ab)

-  Capsule IgG Ab

-  Presence indicates previous or current infection

-  Will not be present if vaccination

-  Usually positive life long

-  Small % false positives

 

Hepatitis B Core IgM (HBcIgM)

-  Indicates acute infection

 

Hepatitis B e Antigen (HBeAG)

-  Indicates active replication

-  Highly infective stage of infection

-  BUT some subtypes do not produce it at all

 

Hepatitis B Viral DNA (HBV DNA)

-  Indicates active replication

-  Allows subtyping

 

 

 

References

 

Western Diagnostic Group – Guide to Hepatitis Serology 2010