Hepatic Encephalopathy

Abstract

Hepatic encephalopathy (HE) is one of the most debilitating manifestations of acute or chronic liver disease and/or portosystemic shunting. The clinical manifestations of HE span a wide spectrum of neurologic or psychiatric abnormalities, ranging from subclinical neuropsychological disturbances to coma. HE severely affects the lives of patients and their caregivers and results in the use of more health care resources in adults than other manifestations of hepatic dysfunction. To date, there are insufficient clinical studies and standardized definitions, making the diagnosis, classification, and treatment of HE challenging. This review covers the epidemiology, pathophysiology and pathogenesis, diagnosis, differential diagnosis, treatment, and follow-up of HE. Figures show the numerous processes and mechanisms involved in the pathogenesis of HE and ammonia trafficking and metabolism within the body. Tables list the four factors that dictate categorization and grading of HE, differential diagnosis of HE, summary of testing used for minimal HE and covert HE with associated advantages and/or disadvantages, and precipitating causes of HE in patients with cirrhosis. This review contains 2 highly rendered figures, 4 tables, and 77 references. Key words: chronic liver disease; covert hepatic encephalopathy; hepatic encephalopathy; minimal hepatic encephalopathy; overt hepatic encephalopathy; transjugular intrahepatic portosystemic shunt