Selection for acute liver failure: Have we got it right?

1. The interplay of four factors determines the outcome in Acute Liver Failure (ALF). Current criteria used for prognosis address each of these factors. a. Hepatic regeneration: Age, poor prognostic etiologies (drug, idiopathic ALF) b. Hepatocellular failure: INR, Bilirubin c. Encephalopathy and brain edema: Stage III/IV hyperacute vs acute/subacute d. Multiorgan failure (MOF): pH 2. In hyperacute liver failure, exemplified by acetaminophen-induced injury, prognostic criteria have focused on the course of encephalopathy and of multiorgan failure. In non-acetaminophen induced ALF, prognostic criteria reflect a greater role of hepatic regeneration in outcome. 3. Prognostic indices combine features of these four factors. The Kings College criteria (KCC) have been shown to have a better performance than the Clichy criteria. The KCC appear to have a higher specificity than sensitivity for acetaminophen-induced ALF, while its negative predictive value for non-acetaminophen induced ALF is unfortunately low. 4. Newer prognostic markers have been proposed, including serum phosphate and alpha fetoprotein as markers of regeneration and blood lactate, a reflection of MOF and hepatocellular failure. They are likely to complement the KCC rather than replace them. 5. Clinical judgement is still needed to weigh management options in this disease.