Anti-HBc IgG and IgM antibodies are the body’s first response to a hepatitis B virus (HBV) infection. These antibodies are directed against a portion of the HBV called “core”. Anti-HBc IgG and IgM appear shortly after the symptoms and onset of measurable virus surface antigen (HBsAg). IgM arrive first and are then replaced by IgG. Total Anti-HBc (IgG plus IgM) are interpreted in light of clinical factors and the results of other hepatitis B markers, particularly HBsAg and anti-HBs.
A negative total anti-HBc result may indicate the absence of a recent or previous HBV infection (negative HBsAg and anti-HBs). However, a developing infection cannot be ruled out. The combination of negative total anti-HBc and HBsAg results, but positive anti-HBs results indicates an individual that has been vaccinated against hepatitis B. In combination with positive HBsAg/negative anti-HBs, a negative total anti-HBc test may indicate an individual in the acute phase of the disease or a reactivation of the virus in a chronic carrier.
A positive total anti-HBc result may indicate that the individual has eliminated the virus and is now immune (negative HBsAg/positive anti-HBs) or is in a recovery phase (negative HBsAg and anti-HBs / negative or positive anti-HBc IgM). When combined with a positive HBsAg, an active chronic infection may be suspected.