Clinical and Interpretive

This test is used to diagnose acute hepatitis B infection and to identify acute hepatitis B virus (HBV) infection in the serologic window period when hepatitis B surface antigen and anti-hepatitis B surface are negative. It is also used to differente between acute and chronic/past hepatitis B infection in the presence of positive anti-hepatitis B core.

Hepatitis B virus (HBV) is a DNA virus that is endemic throughout the world. In the initial (acute) phase of infection, anti-hepatitis B core antibodies (anti-HBc) consist almost entirely of the IgM antibody class and appear shortly after the onset of symptoms. Anti-HBc IgM antibody can be detected in serum and is usually present for up to 6 months after acute HBV infection. Anti-HBc IgM may be the only serologic marker of a recent hepatitis B infection detectable following the disappearance of hepatitis B surface antigen (HBsAg) and prior to the appearance of hepatitis B surface antibody (anti-HBs) (ie, serologic window period).

A positive result indicates recent acute hepatitis B infection.

A negative result suggests lack of recent exposure to the virus in preceding 6 months.

The predictive value of a positive anti-hepatitis B core (anti-HBc) IgM test result is low when used to test specimens from patients with low prevalence of acute hepatitis B virus infection.