[Persistence of hepatitis B virus in children after interferon-alpha therapy despite the seroconversion in HBsAg/anti-HBs system].

OBJECTIVE: The aim of our study was to assess: (1) whether seroconversion to IgG anti-HBs, induced by IFN-alpha therapy in children with chronic active hepatitis B, is maintained 4-10 years after treatment; and (2) whether HBV-DNA is present in circulation despite the synthesis of anti-HBs. METHODS: Serum samples were collected from 38 patients and serological markers of HBV were determined in each of them. HBV-DNA was determined by PCR in anti-HBs positive sera. Serum samples obtained from 19 subjects with a complete spontaneous seroconversion after acute HBV served as controls. RESULTS: Four to 10 years after therapy, anti-HBs were present in ca. 97.4% patients with GMT value of 775 IU/L vs 127 IU/L found in controls. HBsAg was found in 2/38 subjects. In 13 out of 37 patients (35.1%) free and/or bound HBV-DNA was present. CONCLUSIONS: This study showed that seroconversion induced by IFN-alpha may not be a sustained phenomenon. HBV-DNA may persist for a long time after therapy despite the anti-HBs synthesis.