[Histopathology of the alcoholic hepatitis and mesenchymal cells].

Alcoholic hepatitis is one of the type of alcoholic liver diseases (ALD). There are definite histopathological criteria; presence of Mallory bodies and PMN leukocytes. In Japan, it has been believed that alcoholic hepatitis is very rare and alcoholic fibrosis is common type in ALD. On the other hands, some american, authorities consider that severe ballooning of hepatocytes with slight fibrosis is also inflammatory state, alcoholic hepatitis. Histological criteria is controversial. Generally, fibrosis believed to be a histological marker of chronic inflammation. However, in ALD, there is primary fibrosis, specific fibrosis produced by direct stimulation of alcohol or its metabolites on mesenchymal cells. On the fibrogenesis in hepatic lobules, the mesenchymal cells represented by Ito cells play main role. Ito cells show morphological and immunohistochemical heterogeneity depending on its physiological condition. On the other hand, Ito cells also show various degrees of transitional changes associated with fibrogenesis. Then, morphological and immunohistochemical appearance of Ito cells is very complicated. Recently, it is considered that these differences means different cell populations of the fibroblast lineage with fibrogenic potential.