Abstract: Objective The purpose of this study was to investigate the ultrastructural changes of liver tissues in children with Wilson]s disease (WD), non-alcoholic fatty liver diseases (NAFLD) and autoimmune hepatitis (AIH). Methods 37 children with WD, 20 children with NAFLD and 17 children with AIH were encountered in our hospital between December 2018 and February 2022, and all children underwent liver biopsies for routine and ultrastructural examination. Results The proportion of liver fibrosis and copper staining positive in children with WD were 78.4% and 29.7%, significantly higher than 10.0% and 0.0%(P<0.05) in children with NAFLD, while the proportion of macrovesicular steatosis and lipid droplets were 62.2% and 75.7%, significantly lower than 95.0% and 95.0%(P<0.05)in children with NAFLD; the proportion of hepatocyte nucleus vacuolar degeneration in children with WD was 59.5%, much higher than 17.6%(P<0.05) in children with AIH, while the proportion of portal inflammation, interfacial hepatitis, lobular inflammation, plasma cell infiltration and hepatocyte rosette structure were 78.4%, 10.8%, 64.9%, 5.4% and 24.3%, significantly lower than 100.0%, 88.2%, 82.4%, 64.7% and 76.5% in children with AIH (P<0.05); as for the ultrastructural changes, the proportion of mitochondrial pleomorphism, crest tip dilatation, membrane replication and increased matrix density in children with WD were 81.1%, 83.8%, 62.2% and 62.2%, significantly higher than 30.0%, 15.0%, 5.0% and 5.0%(P<0.05) in children with NAFLD or 23.5%, 11.8%, 5.9% and 5.9%(P<0.05) in children with AIH, while the proportion of quasicrystal inclusion was 0.0%, much lower than 15.0%(P<0.05) in children with NAFLD. Conclusion The liver histo-pathological changes, including ultrastructural features, in children with WD, NAFLD and AIH are specific, which could provide evidences for diagnosis of them.

Key words: Wilson’s disease, Non-alcoholic fatty liver diseases, Autoimmune hepatitis, Liver histo-pathology, Ultrastructure