Morphologic and immunohistochemical features of fulminant delta hepatitis.

Recent studies have indicated that some cases of fulminant hepatitis that were ostensibly type B were actually acute viral hepatitis, types B and delta, or persistent hepatitis, type B with superimposed acute delta infection. Histologic characterization of the various types has not yet been undertaken. Within ten to 37 days of the onset of initial symptoms, liver tissues from a total of 16 patients who had acute delta hepatitis with fulminant clinical courses were examined. Tissues were from biopsies in nine cases and from autopsies in seven. Based on the serologic absence of IgM hepatitis B core antibody, chronic forms of hepatitis B with acute delta infection were diagnosed in five of the 16 patients. The underlying liver disease in three of these five patients was identifiable as chronic active hepatitis with fibrosis, and that in the others was apparently persistent hepatitis B. Coded liver tissues from these seven autopsies were evaluated without the knowledge of serologic diagnosis for qualitative and quantitative light microscopic features, together with autopsy liver tissues from five patients with fulminant B hepatitis without serologic evidence of delta infection and five patients with fulminant non-A, non-B hepatitis. No specific features that would allow discrimination among these three types of hepatitis were found.