Do we have to rethink serologic markers used to diagnose hepatitis B infection?

The recent addition of testing volunteer blood donors for antibody to hepatitis B core antigen (anti-HBc) has raised questions not apparent when such testing is applied to hepatitis B (HB) infected patients. The review of published studies, and our own, demonstrates that it is difficult to evaluate false positive results. Some patients appear to lose antibody to hepatitis B surface antigen (anti-HBs) but not antibody to hepatitis B core antigen (anti-HBc), thus raising the possibility of disease transmission. It is anticipated that additional investigation of individuals positive for anti-HBc only by response to hepatitis B vaccine permits clarification of their immune status and absence of infectivity.