General Principles

• ALF is a condition that includes evidence of a combination of coagulation abnormalities and any degree of mental alteration (encephalopathy) in a patient without preexisting liver disease and with an illness of <26 weeks in duration.
• In 20% of cases, no clear cause is identified. Acetaminophen hepatotoxicity and viral hepatitis are the most common causes of ALF. Other causes include AIH, drug and toxin exposure, ischemia, acute fatty liver of pregnancy, WD, and Budd–Chiari syndrome.
• Acute inflammation with varying degrees of necrosis and collapse of the liver’s architectural framework are the typical histologic changes seen in ALF.