[Clinical relevance of immunoglobulin M antibody fraction against hepatitis B core antigen (anti-HBc-IgM) (author's transl)].

Forty-four anti-HBc positive patients with various liver diseases were followed up over 2-3 years with enzyme-immunological determinations of the IgM fraction of anti HBc (anti-HBc-IgM). Patients with acute virus hepatitis B (n = 10) had anti-HBc-IgM titres greater than or equal to 10(-3) in the acute phase. In the reconvalescent phase the titre decreased significantly but was still detectable at a level of 10(-1) two years after the onset of the disease. In patients with HBs-antigen positive chronic active hepatitis (n = 25) the anti-HBc-IgM was always detectable when HBe-antigen was positive. Patients with HBe-antigen negative chronic active hepatitis B showed various anti-HBc-IgM findings. Patients with liver diseases not due to hepatitis B virus infections (n = 9) were always anti-HBc-IgM negative. Thus with the help of anti-HBc-IgM determinations acute hepatitis B virus infection can be diagnosed in HBs-antigen negative people. On the other hand it is not suitable for differentiation between acute and chronic hepatitis B infections in HBs-antigen positive persons.