A neuropsychiatric syndrome caused by acute or chronic hepatic insufficiency.
Symptoms vary in severity from a mild alteration in mental state to coma but are often reversible with treatment.
Causation is thought to be multi-factorial, resulting in brain exposure to ammonia that has bypassed the liver through portosystemic shunting.
Diagnosis is based on reported neurological deficits combined with laboratory abnormalities showing severe liver dysfunction.
Treatment approaches include providing supportive care (such as preventing aspiration), correcting precipitating factors, and reducing gastrointestinal production of ammonia.
Hepatic encephalopathy (HE) is a brain dysfunction caused by liver insufficiency and/or portosystemic shunt. It manifests as a wide spectrum of neurological or psychiatric abnormalities ranging from subclinical alterations to coma.
This topic discusses HE in patients with cirrhosis. For a discussion of HE in acute liver failure, see our Acute liver failure topic.
History and exam
Key diagnostic factors
- presence of risk factors
- mood disturbances
- sleep disturbances
- motor disturbances
- advanced neurological deficits
Other diagnostic factors
- palmar erythema
- spider angiomata
- peripheral oedema
- gastrointestinal bleeding
- excessive protein intake
- metabolic alkalosis
- sedative use
- hepatic or portal vein thrombosis
- portacaval shunt
- renal impairment
1st investigations to order
- liver tests
- serum glucose
- coagulation profile
- serum electrolytes
- urea and creatinine
- arterial or venous blood gas
- urine culture
- blood culture
- urine toxin screen
- head CT scan
Investigations to consider
- ammonia level
- lumbar puncture
- abdominal paracentesis
Jasmohan S. Bajaj, MD, FAASLD, FACG, AGAF, FRCP (London), MS
Professor of Medicine
Department of Internal Medicine
Division of Gastroenterology, Hepatology and Nutrition
Virginia Commonwealth University
JB’s institution has received funding for research from Valeant Mallinckrodt and Grifols. JB has been on advisory boards for Valeant, Mallinckrodt, and Norgine.
Dr Jasmohan Bajaj would like to gratefully acknowledge Dr Emily Speelmon, Dr Robert Hyzy, and Dr Meilan Han, previous contributors to this topic.
ES, MH, and RH declare that they have no competing interests.
Sammy Saab, MD, MPH, AGAF
Professor of Medicine
Department of Internal Medicine and Surgery
David Geffen School of Medicine
SS is a member of the speaker bureau and advisory board for Salix.
Jorge A. Marrero, MD
Assistant Professor of Medicine
Division of Gastroenterology
University of Michigan
JAM declares that he has no competing interests.
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