Chronic HDV (hepatitis delta virus) hepatitis. Intrahepatic expression of delta antigen, histologic activity and outcome of liver disease.

The expression of intrahepatic delta antigen (HDAg) was studied in relation to the morphologic features of HDV hepatitis and the outcome of liver disease. The study was performed in 101 patients followed up for an average of 12 years; one or more liver biopsies were available from each patient, giving a total of 167 specimens. The histologic features were assessed using numerical scores. A significant positive relation was observed between the number of HDAg-positive cells and the extent of portal inflammation (Spearman's rank coefficient 0.75). The highest degree of inflammation and intrahepatic expression of HDAg was found before the elimination of the virus, while the outcome of HDV disease was unrelated to the severity of the initial morphologic lesion. These results suggest that the individual immune response may play an important role in the pathogenesis of HDV hepatitis.