The diagnostical significance of antibodies against hepatitis B core antigen.

The frequency of hepatitis B was examined using three serological parameters: HBsAg, antiHBs and antiHBc. All three substances were detected qualitatively by means of sensitive radioimmunological techniques. Of 1216 patients with acute hepatitis, 55 percent were HBsAg and antiHBc positive on admission to hospital. A further 17.8 percent had no HBsAg but were antiHBc positive and also partly antiHBs positive. These cases can be divided into 2 groups: In one group, in 8.6 percent of patients had a high antiHBc concentration during the acute phase. Similar antiHBc concentrations were seldom found (0.04 percent) in HBsAg negative blood donors. AntiHBs in the patients was at first mainly negative and then appeared during reconvalescence. These cases were considered to be acute hepatitis type B, although HBsAg was absent. In the second group, comprising 9.2 percent of the patients, antiHBc was present in low concentrations and in majority of cases antiHBs had been present from the beginning. The same antibody constellation was found in 3.6 percent of 2341 blood donors. In the group of patients it is supposed that the acute hepatitis present is not of type B and has a different aetiology. The low concentration of antibody is interpreted to be a sign of an earlier HBV-infection.