Clinical and epidemiological significance of hepatitis delta virus (HDV) infection in chronic HBV carriers in Portugal.

This study demonstrated that in Portugal HDV infection occurs in 17.3% of HBsAg chronic carriers and chronic HDV infection in 8.4%. As in Northern European countries, HDV infection in Portugal is predominantly found in drug-addicts. Our findings also confirm that HDV infection is associated with an active and progressive liver disease. In delta Ag positive CLD serum HBV-DNA was detected in 10 of 19 cases and was present at low levels. In contrast 52 of 84 delta Ag negative were serum HBV-DNA positive and 48.1% of these had high serum HBV-DNA levels. Ninety per cent of delta Ag positive CLD with serum HBV-DNA positive were drug addicts. These findings indicate that in chronic HDV infection synthesis of HBV is reduced and suggest namely that in drug-addicts their disease derived from the cumulative pathogenic effect of both HBV and HDV. In follow-up biopsy a significantly younger mean age and significantly deterioration of carriers with HDV infection was observed, suggesting that HDV infection accelerates the natural history of HBV related liver disease.