Looking Past Orthotopic Liver Transplantation: A Review of Emerging Strategies for Managing Acute and Acute-on-Chronic Liver Failure

Abstract

Acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) are both characterized by an acute insult leading to dysfunction of the liver and often other organs. Acute liver failure is defined by coagulopathy (INR > 1.5) and hepatic encephalopathy in the context of a new hepatic insult within the past 26 weeks [1]. It is relatively rare, with approximately 2000 cases per year diagnosed in the United States [2]. ACLF refers to an acute decompensation of chronic liver disease, but lacks a single clear definition [1]; the definitions used the most in studies discussed herein are reviewed in Table 17.1. Orthotopic liver transplant (OLT) is a valuable therapy for both conditions, but as with chronic liver failure, the demand for organs exceeds the supply. In the absence of liver transplant, the mortality of ALF has been estimated at >80% in some studies [1]. While the inconsistent definition makes ACLF mortality difficult to determine, a review based on the Asian Pacific Association for the Study of the Liver (APASL) and the European Foundation for the Study of Chronic Liver Failure (EASL-CLIF) definitions found a 90-day transplant-free mortality of about 50% [5].