Snapshot A 45-year-old man with a history of alcoholic cirrhosis is found on the sidewalk with altered mental status. He is brought in to the emergency room by the police. He has had multiple similar visits for intoxication. This time, however, he is noted to be markedly lethargic and jaundiced. On physical exam, he has pronounced asterixis, ascites, and other signs of liver disease such as telangiectasias and palmar erythema. Laboratory evaluation reveals negative serum alcohol levels but elevated ammonia and liver enzymes. A hepatic ultrasound shows a hyperechoic mass in his liver, which is concerning for malignancy in the setting of chronic cirrhosis and was thought to be the possible trigger for his episode of hepatic encephalopathy. Introduction Overview a reversible complication of liver failure characterized by altered mental status and asterixis often precipitated by acute stressors such as dehydration or infection Epidemiology incidence 30-40% of patients with cirrhosis risk factors alcohol use hepatitis Etiology acute triggers dehydration infection gastrointestinal bleed fluid and electrolyte abnormalities sedatives hepatocellular carcinoma transjugular intrahepatic portosystemic shunt (TIPS) Pathogenesis mechanism ↓ ammonia clearance due to liver dysfunction login to view 1 more bullet portosystemic shunts causing blood to bypass the liver ammonia is neurotoxic login to view 3 more bullets Associated conditions acute liver failure cirrhosis other complications of cirrhosis include portal hypertension, esophageal varices, and hepatocellular carcinoma Prognosis hepatic encephalopathy is reversible Classification Classification by underlying disease type A acute liver failure type B portosystemic bypass or shunting with preserved liver function type C cirrhosis Presentation Symptoms common symptoms mood changes slow to respond unsteadiness Physical exam inspection signs of liver disease login to view 4 more bullets asterixis login to view 1 more bullet altered mental status coma/stupor in severe cases Imaging CT or MRI of the head indication rule out intracranial hemorrhage or mass as a cause of encephalopathy findings cerebral edema Studies Serum labs ↑ ammonia also check liver function panel blood urea nitrogen electrolytes Differential Other metabolic encephalopathies diabetic ketoacidosis distinguishing factor login to view 1 more bullet uremic encephalopathy distinguishing factor login to view 1 more bullet acute alcoholic intoxication distinguishing factor login to view 1 more bullet Treatment Nonoperative correct precipitating factor and electrolyte derangements lactulose mechanism login to view 1 more bullet indication login to view 1 more bullet rifaximin mechanism login to view 1 more bullet indication login to view 1 more bullet Complications Persistent learning impairment