Hepatic encephalopathy: from pathophysiology to treatment

Area of Science:

• Hepatology
• Neurology
• Gastroenterology

Background:

• Hepatic encephalopathy (HE) is a neuropsychiatric syndrome linked to liver dysfunction and portosystemic shunting.
• Cirrhosis is the primary liver disease leading to HE, often precipitated by factors like infections or bleeding.
• Intestinal ammonia production by bacteria is a key factor in HE pathogenesis, alongside other mechanisms like GABA-benzodiazepine system alterations and manganese accumulation.

Purpose of the Study:

• To summarize the understanding of hepatic encephalopathy (HE) pathophysiology, clinical presentation, and management strategies.
• To highlight the multifactorial nature of HE, involving ammonia toxicity, neurotransmitter imbalances, and potential neurotoxicant accumulation.
• To discuss current and future therapeutic approaches, including ammonia reduction, supportive care, and definitive treatments like liver transplantation.

Main Methods:

• Review of existing literature on hepatic encephalopathy.
• Analysis of pathophysiological mechanisms, including ammonia metabolism and neurochemical changes.
• Evaluation of clinical manifestations and treatment modalities for HE.

Main Results:

• HE presents with a spectrum of neurological symptoms, from subtle cognitive deficits to deep coma.
• Precipitating factors significantly influence HE onset and severity.
• Multiple pathophysiological pathways contribute to HE, including ammonia toxicity, altered neurotransmission, and neuroinflammation.

Conclusions:

• Effective HE management requires addressing precipitating factors and reducing ammonia levels.
• Emerging therapies and artificial liver support systems show promise for future treatment.
• Liver transplantation remains the definitive curative option for eligible patients with chronic HE.