Acute kidney injury as a causal factor in mortality associated with hepatorenal syndrome.

PURPOSE: We examine how acute kidney injury (AKI) contributes to mortality in patients with liver failure. CONTENT: Hepatorenal syndrome (HRS) is a form of AKI in cirrhotic patients, which is defined as a purely physiologic derangement in renal function without any effect on renal parenchyma. Recent literature challenges this understanding. Little attention is paid to the presence of renal pathology and inflammatory alterations that occur as a result of HRS and their contribution to morbidity and mortality. In this paper, we propose that any type of AKI in the presence of liver disease is an inflammatory condition. The combination of AKI and liver failure produces a "toxic milieu" of cytokines, chemokines, and nitric oxide pathway metabolites that directly cause endothelial dysfunction affecting multiple organ systems. These global effects contribute to the increased short- and long-term mortality which has been established in the epidemiologic literature.