[Global differences and challenges in the definition of acute liver failure].

Acute liver failure (ALF) is a critical syndrome characterized by sudden deterioration of liver function, coagulopathy, and hepatic encephalopathy, with a very high mortality rate. However, the global ALF diagnostic criteria exhibit significant heterogeneity, with remarkable differences among countries in terms of disease course duration, grading requirements for hepatic encephalopathy, exclusion principles for basic liver disease, and accompanied symptoms. This inconsistency hinders accurate determination of liver transplantation timing, epidemiological comparisons, prognostic assessments, and cross-border research. This article systematically analyzes the core differences in ALF definitions among liver disease-related associations in China, Japan, Europe, and America; explores their impact on clinical practice and scientific research; and proposes strategies such as multicenter collaboration and molecular typing to promote global integration and research advancement for ALF definitions.