Abstract
Acute-on-chronic liver failure (ACLF) is a distinct clinical syndrome characterized by an acute decompensation of chronic liver disease in association with extrahepatic organ failure(s) and a high short-term mortality. Despite its increasing clinical relevance, there is no internationally standardized definition of ACLF to date. This review provides a comprehensive overview of current ACLF definitions, underlying pathogenic mechanisms, frequent precipitating events, and current treatment strategies. While liver transplantation remains the only curative treatment option, its role in the setting of ACLF is controversially debated, and patient selection remains complex due to high perioperative risk. Thus, the review article describes the current role of liver transplantation in patients with ACLF and describes novel prognostic scoring systems (e.g., TAM core, SALT-M model) that may be helpful in selecting suitable transplant candidates. Further emerging treatment options for ACLF include extracorporeal liver support systems, therapeutic plasma exchange, and immune-modulating approaches targeting toll-like receptor signaling that offer promising adjunctive strategies, though clinical evidence remains limited. Given the high burden and complexity of ACLF, harmonized definitions and evidence-based therapeutic frameworks are urgently needed to improve patient care and optimize transplant prioritization.