[3]:1557[4] The disease process is associated with the development of a coagulopathy of liver aetiology, and clinically apparent altered level of consciousness due to hepatic encephalopathy.

Several important measures are immediately necessary when the patient presents for medical attention.

[5] The diagnosis of acute liver failure is based on a physical exam, laboratory findings, patient history, and past medical history to establish mental status changes, coagulopathy, rapidity of onset, and absence of known prior liver disease respectively.

[3]:1557 Chronic liver failure usually occurs in the context of cirrhosis, itself potentially the result of many possible causes, such as excessive alcohol intake, hepatitis B or C, autoimmune, hereditary and metabolic causes (such as iron or copper overload, steatohepatitis or non-alcoholic fatty liver disease).

People with ACLF can be critically ill and require intensive care treatment, and occasionally a liver transplant.