hepatorenaal

Hepatorenal syndrome (HRS), sometimes written as hepatorenaal, is a form of functional kidney failure that occurs in people with advanced liver disease, most often cirrhosis with portal hypertension. It is defined by a progressive decline in kidney function in the absence of an identifiable intrinsic kidney disease, usually occurring in the setting of ascites and severe hepatic dysfunction. HRS is considered a diagnosis of exclusion after other causes of acute kidney injury have been ruled out.

The condition is driven by circulatory changes associated with liver failure. Severe splanchnic vasodilation reduces effective arterial blood volume, triggering activation of vasoconstrictor systems such as the renin-angiotensin system and sympathetic nerves. This leads to marked renal vasoconstriction and a fall in glomerular filtration rate. HRS is traditionally classified into two forms: type 1, a rapid and progressive decline in kidney function, and type 2, a more indolent course often associated with refractory ascites. In recent criteria, a broader category of hepatorenal syndrome–acute kidney injury (HRS-AKI) has been used to describe the spectrum of kidney injury in cirrhosis.

Diagnosis relies on the presence of cirrhosis with ascites, evidence of kidney dysfunction, and exclusion of other causes such as shock, nephrotoxins, or intrinsic kidney disease. Urinalysis is typically bland, with low urine sodium and a relatively low fractional excretion of sodium, and imaging shows normal renal anatomy.

Management focuses on treating the underlying liver disease and supporting kidney function. Measures include withdrawal of nephrotoxic drugs, management of infections, and intravenous albumin combined with vasoconstrictors (such as terlipressin or norepinephrine) to improve renal perfusion. In selected cases, transjugular intrahepatic portosystemic shunt or other interventions may be considered. Liver transplantation remains the definitive therapy for eligible patients. The prognosis is guarded, especially for type 1 HRS, and survival improves with liver transplant.