Pathological study of 130 cases of nonalcoholic fatty liver disease based on NASH-CRN system

Abstract

To summarize the pathological features of nonalcoholic liver disease (NAFLD) in China based on a histological scoring system for NAFLD designed by the Pathology Committee of NASH Clinical Research Network (NASH-CRN), the specimens of liver needle biopsies from 130 patients with NAFLD were histopathologically analyzed by haematoxylin eosin, reticular fiber and Masson trichrome stain. Immunohistochemistry staining was used to exclude non-NAFLD cases combined with clinical data. Hepatic steatosis, lobular inflammation, hepatocytic ballooning and fibrosis were presented widespread in NAFLD liver tissues. Furthermore, macrovesicular steatosis predominantly located in acinar zone 3 was the main histologic feature of NAFLD and lobular inflammation was usually presented mildly. Hepatocyte ballooning was observed in 94.6% of all 130 cases. Mild perisinusoidal fibrosis and periportal fibrosis were often observed in stage 1 cases. According to the statistic analysis, hepatic steatosis was positively correlated with lobular inflammation, hepatocytic ballooning and fibrosis (r = 0.587, 0.488, 0.374, respectively, all P value<0.01). The number of microgranulomas, lipogranulomas and apoptotic bodies increased following severity of steatosis, lobular inflammation and fibrosis. Meanwhile, the number of megamitochondria and glycogen nuclei was paralleveled to the degree of hepatocytic ballooning (P value all<0.01). We suggest that the role of portal inflammation should be emphasized besides hepatic steatosis, lobular inflammation, hepatocyte ballooning and fibrosis in diagnosis and evaluation of NAFLD. It needs to be further verified whether microgranulomas, lipogranulomas and apoptosis bodies could be used as histopathological markers of development of AFLD. The number of megamitochondria is more frequently be found in NAFLD, while in alcoholic liver diseases was Mallory bodies.