Hepatitis D virus (delta agent) superinfection in an endemic area of hepatitis B infection: immunopathologic and serologic findings.

In 86 Chinese patients with histologically proven hepatitis B surface antigen (HBsAg) positive chronic hepatitis and serum alanine aminotransferase levels exceeding 200 U/l, antibody to hepatitis D antigen (HDAg) was detected more frequently in sera from hepatitis B e antigen (HBeAg) negative patients (11/35, 31.4%) than in HBeAg positive (4/51, 7.8%) patients (p less than 0.02). 10 liver biopsy specimens (76.9%) from 13 chronic hepatitis B patients with superimposed hepatitis D virus (HDV) infection, showed positive staining for HDAg in their hepatocytes. Neither HBsAg nor hepatitis B core antigen (HBcAg) was found in the liver in 12/13 patients with superimposed HDV infection. However, in liver biopsy specimens from 42 patients without HDV superinfection, HBsAg was stained positively in 41 patients (97.6%), and HBcAg in 24 patients (47.1%). Using dot blot hybridization technique, serum hepatitis B virus (HBV) DNA was detected in 62.1% (41/66) of patients without HDV superinfection, while it was detected only in 10.0% (1/10) of patients who had HDV superinfection. It is concluded that HDV superinfection plays a significant role in Taiwan in HBeAg negative chronic hepatitis B patients with clinical "exacerbation". The data show clear evidence of HDV interfering with the replication of HBV.