Hepatic encephalopathy

Hepatic encephalopathy
Other names	Portosystemic encephalopathy, hepatic coma,[1] coma hepaticum
Micrograph of Alzheimer type II astrocytes, as may be seen in hepatic encephalopathy
Specialty	Gastroenterology
Symptoms	Altered level of consciousness, mood changes, personality changes, movement problems[2] slurred speech, Sleep problems, Anxiety or irritability, Muscle twitches (myoclonus), Difficulty concentrating or short attention span, Flapping hand motion (asterixis), Reduced alertness, Cognitive impairment (confused thinking or judgment).[3]
Complications	hepatic coma.[3]
Types	Acute, recurrent, persistent[4]
Causes	Liver failure[2]
Risk factors	Infections, GI bleeding, constipation, electrolyte problems, certain medications[5]
Diagnostic method	Based on symptoms after ruling out other possible causes[2][6]
Differential diagnosis	Wernicke–Korsakoff syndrome, delirium tremens, hypoglycemia, subdural hematoma, hyponatremia[1]
Treatment	Supportive care, treating triggers, lactulose, liver transplant[1][4]
Prognosis	Average life expectancy less than a year in those with severe disease[1]
Frequency	Affects >40% with cirrhosis[7]

Hepatic encephalopathy (HE) is an altered level of consciousness as a result of liver failure.^[2] Its onset may be gradual or sudden.^[2] Other symptoms may include movement problems, changes in mood, or changes in personality.^[2] In the advanced stages it can result in a coma.^[4]

Hepatic encephalopathy can occur in those with acute or chronic liver disease.^[4] Episodes can be triggered by infections, GI bleeding, constipation, electrolyte problems, or certain medications.^[5] The underlying mechanism is believed to involve the buildup of ammonia in the blood, a substance that is normally removed by the liver.^[2] The diagnosis is typically based on symptoms after ruling out other potential causes.^[2][6] It may be supported by blood ammonia levels, an electroencephalogram, or a CT scan of the brain.^[4][6]

Hepatic encephalopathy is possibly reversible with treatment.^[1] This typically involves supportive care and addressing the triggers of the event.^[4] Lactulose is frequently used to decrease ammonia levels.^[1] Certain antibiotics (such as rifaximin) and probiotics are other potential options.^[1] A liver transplant may improve outcomes in those with severe disease.^[1]

More than 40% of people with cirrhosis develop hepatic encephalopathy.^[7] More than half of those with cirrhosis and significant HE live less than a year.^[1] In those who are able to get a liver transplant, the risk of death is less than 30% over the subsequent five years.^[1] The condition has been described since at least 1860.^[1]