Table 1.

Main features of alcoholic and nonalcoholic fatty liver disease at histology

Alcoholic Liver Disease	Non Alcoholic Fatty Liver Disease
Macrovescicular steatosis is largely represented	Macrovescicular steatosis is less represented
Mallory hyaline is recurrent	Mallory hyaline is not occurring often
Swollen hepatocytes/Ballooned cells are more frequent	Swollen hepatocytes/Ballooned cells are less present
Lobular infiltration of polymorphonuclear leukocytes (neutrophils) is severe	Usually, there is mild lobular infiltration with foci of mononuclear cell clusters, and occasional eosinophils or neutrophils.
Inflammatory cell infiltration is more pronounced	Inflammatory cell infiltration is less marked
Perivenular fibrosis with the chicken wire” pattern of fibrosis is common	Fibrosis typically begins in zone 3 with the characteristic pericellular “chicken wire” pattern
Fibro-obliterative/inflammatory lesions of the outflow veins, alcoholic foamy degeneration are present	Fibro-obliterative lesions are not constant and foamy degeneration is rare
Acute cholestasis is often present	Intrahepatic cholestasis is associated with more advanced histological impairment
Phlebosclerosis, and (less commonly) lymphocytic phlebitis are present	Phlebosclerosis is rare
There is solid fibrosis	There is lattice fibrosis
Megamitochondria, bile stasis, hemosiderin deposition, vacuolic nuclei, and lipogranuroma are scarcely represented	Megamitochondria, bile stasis, hemosiderin deposition, vacuolic nuclei, and lipogranuroma are more often represented
Bridging necrosis is frequent	Bridging necrosis is rare
Fibrosis/cirrhosis is more frequent	Fibrosis/cirrhosis is less frequent

The features at histology overlap, and it is not easy to clearly separate the two entities