Hepatorenal Syndrome: Updates on Definition, Classification, Pathophysiology and Treatment Options

Hepatorenal syndrome (HRS) is a severe complication of advanced liver disease, characterized by renal dysfunction in the absence of intrinsic kidney disease. It is associated with high mortality, necessitating early recognition and prompt treatment. In this review, we summarize the latest in pathophysiology, diagnosis, classification and treatment of hepatorenal syndrome relevant to a consulting interventional radiologist. The diagnosis and classification of HRS has recently been updated by the International Club of Ascites (ICA) and kidney disease improving global outcomes (KDIGO) to include more subcategories that better reflect disease severity and prognosis. Greater insights have also been obtained into the pathophysiology of HRS, currently understood to be a complex manifestation of hemodynamic disturbances due to portal hypertension, systemic inflammation, oxidative stress, and biliary injury. We discuss the role of laboratory biomarkers in diagnosis and prognosis along with associated pitfalls. Treatment options are reviewed starting with first line medical management, adjunctive renal replacement therapy, and liver transplantation. Finally, we review the evidence to date investigating transjugular intrahepatic portosystemic shunt (TIPS) creation in this population, focusing on expected efficacy for specific subpopulations and current gaps in knowledge, all driving practical recommendations for when the procedure should be considered.