Hepatic encephalopathy: diagnosis and management

Type C hepatic encephalopathy (HE) is a brain dysfunction caused by severe hepatocellular failure or presence of portal-systemic shunts in patients with liver cirrhosis. In its subclinical form, called "minimal hepatic encephalopathy (MHE), only psychometric tests or electrophysiological evaluation can reveal alterations in attention, working memory, psychomotor speed and visuospatial ability, while clinical neurological signs are lacking. The term "covert" (CHE) has been recently used to unify MHE and Grade I HE in order to refer to a condition that is not unapparent but also non overt. "Overt" HE (OHE) is characterized by personality changes, progressive disorientation in time and space, acute confusional state, stupor and coma. Based on its time course, OHE can be divided in Episodic, Recurrent or Persistent. Episodic HE is generally triggered by one or more precipitant factors that should be found and treated. Unlike MHE, clinical examination and clinical decision are crucial for OHE diagnosis and West Haven criteria are widely used to assess the severity of neurological dysfunction. Primary prophylaxis of OHE is indicated only in the patient with gastrointestinal bleeding using non-absorbable antibiotics (Rifaximin) or non-absorbable disaccharides (Lactulose). Treatment of OHE is based on the identification and correction of precipitating factors and starting empirical ammonia-lowering treatment with Rifaximin and Lactulose (per os and enemas). The latter should be used for secondary prophylaxis, adding Rifaximin if HE becomes recurrent. In recurrent/persistent HE, the treatment options include fecal transplantation, TIPS revision and closure of eventual splenorenal shunts. Treatment of MHE should be individualized on a case-by-case basis.