Isolated antibodies against the core antigen of hepatitis B virus in HIV-infected patients

The aim of this study was to describe the frequency and significance of isolated antibodies against the hepatitis B virus (HBV) core antigen (HBc) in 2185 HIV-infected patients of the Aquitaine Cohort. Antibodies against HBc were found in 372 subjects (17%). Patients with isolated anti-HBc antibodies were more frequently coinfected with hepatitis C virus (HCV) (58.2%) than those who were anti-HB surface (HBs) antibody positive (22.9%, P<0.001) and those who were dually reactive anti-HBs/anti-HBc antibody positive (27.3%, P<0.001). These results suggest interactions between HBV and HCV. As observed in patients not infected with HIV, the 'anti-HBc-alone' serological profile could reflect essentially late immunity with undetectable anti-HBs antibodies. However, an occult HBV infection cannot be ruled out.