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Hepatic encephalopathy in adults: Clinical manifestations and diagnosis

Peter Ferenci, MD
Section Editor
Bruce A Runyon, MD
Deputy Editor
Kristen M Robson, MD, MBA, FACG


Hepatic encephalopathy describes a spectrum of potentially reversible neuropsychiatric abnormalities seen in patients with liver dysfunction and/or portosystemic shunting. Overt hepatic encephalopathy develops in 30 to 45 percent of patients with cirrhosis and in 10 to 50 percent of patients with transjugular intrahepatic portal-systemic shunts [1,2]. The International Society for Hepatic Encephalopathy and Nitrogen Metabolism consensus defines the onset of disorientation or asterixis as the onset of overt hepatic encephalopathy [3]. Some patients with hepatic encephalopathy have subtle findings that may only be detected using specialized tests, a condition known as minimal hepatic encephalopathy [4-6]. Minimal hepatic encephalopathy is seen in up to 80 percent of patients with cirrhosis [7-13].

Hepatic encephalopathy is often easy to detect in patients presenting with overt neuropsychiatric symptoms. It may be more difficult to detect in patients with chronic liver diseases who have mild signs of altered brain function, particularly if the underlying cause of the liver disease may be associated with neurologic manifestations (such as alcoholic liver disease or Wilson disease).

This topic will review the clinical manifestations and diagnosis of hepatic encephalopathy in adults. The pathogenesis and treatment of hepatic encephalopathy are discussed elsewhere. (See "Hepatic encephalopathy: Pathogenesis" and "Hepatic encephalopathy in adults: Treatment".)


Hepatic encephalopathy is categorized based on four factors: the underlying disease, the severity of manifestations, the time course, and whether precipitating factors are present (figure 1) [14-16].

Underlying disease: A classification scheme based on the underlying disease has been proposed [14,15]:

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Literature review current through: Nov 2017. | This topic last updated: Nov 13, 2017.
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