Pathogenesis of Liver Injury in Acute Liver Failure

Abstract

Acute liver failure (ALF) represents the most severe damage an organ can sustain and can lead to shock, coagulopathy, altered mentation, cerebral edema, renal failure, infection, and, ultimately, multiorgan failure. The US Acute Liver Failure Study Group (ALFSG; available at: acuteliverfailure.org), convened a meeting on October 17 and 18, 2011, and included clinical, translational and fundamental investigators to discuss the pathogenesis of acute hepatocyte injury, how it occurs, and its downstream effects. The ALFSG has, for the past 14 years, carefully collected detailed clinical information and bio-samples from roughly 2000 patients with ALF at 24 tertiary medical centers across the United States. This meeting sought to summarize our current understanding of the pathogenetic factors that drive acute liver injury. These included consideration of (1) the contribution of innate immunity to liver injury, (2) the role of cytokine release in perpetuating liver injury and causing multiorgan failure, (3) mechanisms of apoptosis in ALF, (4) alterations in signal transduction with a focus on the role of c-Jun N-terminal kinase (JNK), (5) the contribution of infection to the pathogenesis of ALF, (6) the emerging centrality of inflammasome and sterile inflammation in the pathogenesis of ALF, (7) systems biology approaches to integrating and ordering the wide array of seemingly massively perturbed effectors in ALF, (8) host genetics and its contribution to ALF susceptibility, including a consideration of the power of next generation sequencing tools as they relate to ALF, and (9) contribution of liver regeneration to counteraction of ALF. Finally, we considered novel therapeutic strategies for ALF based on these pathogenetic concepts.