Fatty liver disease in children: modern paradigms

Background. Fatty liver disease is a term that combines pathological conditions, the common feature of which is the accumulation of lipids in the liver. Fatty liver disease includes several groups of diseases, of which metabolically associated fatty liver disease is the most common in the pediatric population. The term "fatty liver" was first introduced in 1836 by the English scientist Thomas Addison to describe the hepatic histology in a patient with a history of alcohol use disorder. Ten years later, Austrian pathologist Carl von Rokitansky described the histological features of fatty liver disease in children, which was associated with excessive food intake. For over a century, scientists and researchers studied the etiology and pathophysiology of fatty liver disease, as well as its link with fibrosis and cirrhosis. In 1980, the American pathologist Jurgen Ludwig and his colleagues coined the term "non-alcoholic steatohepatitis", while his compatriot, physician and pathologist Fenton Schaffner, introduced the term "non-alcoholic fatty liver disease" in 1986. New knowledge has been accumulated about the multifactorial genesis of metabolically associated fatty liver disease, the role of epigenetic and genetic factors in the development and progression of the disease, which has led to the need to revise terminology and approaches to diagnosis. In 2023, the term nonalcoholic fatty liver disease was proposed instead of non-alcoholic fatty liver disease, as well as updated diagnostic criteria. Currently, there are no approved clinical guidelines for metabolically associated fatty liver disease in children in the Russian Federation. In 2025, a draft of clinical guidelines for the diagnosis and treatment of metabolically associated fatty liver disease in children (non-alcoholic fatty liver disease) was published, which specifies the main criteria for the diagnosis of metabolically associated fatty liver disease in childhood.

Conclusion. This review presents modern ideas about the classification of pediatric metabolically associated fatty liver disease, pays attention to a comparative analysis of diagnostic approaches reflected in foreign and domestic recommendation documents, as well as issues of prevention and treatment of metabolically associated fatty liver disease in children.

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