Delta antigen is currently thought to reflect
superinfection of the liver with a defective RNA virus (delta agent), requiring helper function from hepatitis B virus for its replication. To assess the influence of delta agent on hepatitis B virus replication in patients persistently infected with both viruses and showing chronic
liver disease, we measured serum and liver hepatitis B virus
DNA in
HBsAg-positive chronic
liver disease patients who were either positive or negative for
delta antigen in the liver. Hepatitis B virus
DNA was assayed in the serum of 21 patients with
delta antigen-positive/
HBsAg-positive chronic
liver disease and in 21 patients with
delta antigen-negative/
HBsAg-positive chronic
liver disease matched for
HBeAg/anti-HBe status and underlying liver histology.
HBcAg and
delta antigen in liver was determined by immunofluorescence or immunoperoxidase staining. In
delta antigen-positive/
HBsAg-positive chronic
liver disease, serum hepatitis B virus
DNA was detected transiently in 4 of 21 cases (19%) and was present in these patients at low levels (trace to 2+). In contrast, 9 of 21 (43%)
delta antigen-negative/
HBsAg-positive chronic
liver disease patients were serum hepatitis B virus
DNA positive, and five of these had high serum hepatitis B virus
DNA levels (3+ to 4+). Serum
HBsAg and anti-HBc titers were significantly lower in
delta antigen-positive cases and correlated with reduced amount of
HBcAg in the liver.(ABSTRACT TRUNCATED AT 250 WORDS)