Abstract: Objective To investigate the pathological changes of liver tissues in patients with nonalcoholic fatty liver disease（NAFLD） and type 2 diabetes mellitus （T2DM）. Methods The clinical data of 240 patients with biopsy proven NAFLD were analyzed. Histopathology findings of livers were compared between patients with and without T2DM. Results Out of the 240 patients,there were 80（33.3%） patients with NAFLD and T2DM,and 160 （66.7%） patients with NAFLD without T2DM;Nonalcoholic steatohepatitis （NASH） and liver fibrosis were found in 60 and 20 patients with NAFLD and T2DM,while they were in 68 and 98 patients with NAFLD without T2DM;Patients with NAFLD and T2DM had higher rates of liver fibrosis score≥2（37.5%,n=30）,ballooning score≥2（28.8%,n=23） and Mallory body（27.5%,n=22） compared to patients with NAFLD without T2DM （12.5%,n=20;13.8%,n=22 and 18.8%,n=30,P<0.05）;T2DM was independently associated with NASH （OR = 3.27,95%CI:1.42-7.55） and advanced fibrosis（OR=3.35,95%CI:1.55-7.63） in all patients with NAFLD. Conclusion The liver pathological changes in patients with NAFLD and T2DM might be severe,which warrants more attention.

Key words: Nonalcoholic fatty liver disease, Type 2 diabetes mellitus, Nonalcoholic steatohepatitis, Liver fibrosis, Pathology