Viral and autoimmune hepatitis. Morphologic and pathogenetic aspects of cell damage in hepatitis with potential chronicity.

An extensive and detailed differential presentation of light and electron microscopic aspects of the various types of hepatitis B, non-A, non-B, and autoimmune hepatitis which is of equal practical and diagnostic importance for both clinicians and pathologists, remains to be written. Nowadays, hepatitis A, occurring only as an acute disease, can be diagnosed reliably by means of serological test making liver biopsy in these patients obsolete. The group of patients with hepatitis B, non-A, non-B, and autoimmune type are investigated by light and electron microscopy under the following aspects: - Are there special morphologies of the different groups? - Are the morphologic changes of a nature to provide conclusions concerning the mechanisms of cell and tissue injury? The following, more detailed questions may be added: - Can the assumption that the non-A, non-B agents induce direct cytopathic cell injury (brought forward in the literature) be confirmed by further investigations? - Does the pattern of injury in hepatitis B indicate an immune mediated pathway of cell lesion, as inferred by clinical observations and in vitro investigations? - Is there a correlation between the partially elucidated effector mechanisms in autoimmune hepatitis and histopathologic patterns? One of our comparison groups was made up of normal subjects. As paradigm of a virus induced cytopathic hepatitis, on the other hand, HSV infected mice were investigated by light microscopy and electron microscopy. With the help of immunohistologic and immunoelectron microscopic techniques an in situ characterization of the inflammatory infiltrate was attempted. Hepatitis B. The histopathologic pattern of hepatitis B in our biopsies is characterized by a more ore less dense lymphocytic infiltrate of portal tracts and lobules with a simultaneous polymorphism of hepatocytes. A centrilobular localization of the lymphocytic infiltrates and liver cell damage in many cases is obvious. The lymphocytes are frequently found in close contact with liver cells exhibiting emperipolesis. Ground glass hepatocytes, pathognomonic for hepatitis B, were present in about half of the cases with chronic hepatitis. Non-A, non-B hepatitis. Light microscopic analysis of the cases with non-A, non-B hepatitis exhibits a heterogeneous picture; on account of the known epidemiologic and experimental studies as well as of the clinical data, this was not unexpected.(ABSTRACT TRUNCATED AT 400 WORDS)