• HBsAg negative;
  • HBV-DNA;
  • HBV-sequencing;

We analysed DNA extracted from liver biopsy specimens and serum samples from 42 HCV-RNA-positive/HBsAg-negative subjects with chronic hepatitis. Twenty-eight of them were anti-HBs/anti-HBc-positive (group A), while 14 were negative for all HBV markers (group B). HBV sequences were found in hepatic DNA of 12 cases (11 of group A, one of group B), but in the serum of only two cases of group A. Sequencing analysis of pre-core region of HBV-DNA showed the presence of wild-type HBV in three cases, HBeAg-defective HBV in three cases, and the coexistence of both viral populations in six cases. These results indicate that HBV and HCV infection may coexist in HBsAg-negative chronic hepatitis, particularly in anti-HBs/anti-HBc-positive patients. However, HBV replication appears suppressed in these cases, and this state of latency may involve both wild and HBeAg-defective HBV types.