Investigations

Diagnosis is usually clinical through exclusion of other causes of brain dysfunction. (1,2)

Psychometric tests

• used for diagnosis of covert hepatic encephalopathy
• considered in patients with known or suspected liver cirrhosis
  • who complain of difficulties functioning in everyday life
  • whose relatives have noticed attentional difficulties
  • when employment is directly affected by cognitive impairment
• tests include - psychometric hepatic encephalopathy score (PHES), stroop test, critical flicker frequency (CFF) test, continuous reaction time (CRT) test

EEG

• should be considered if subclinical seizures are suspected
• may show findings such as triphasic waves
• it is nonspecific and may be influenced by accompanying metabolic disturbances, such as hyponatremia as well as drugs.

Computed tomography or magnetic resonance imaging

• should be carried out in all suspected HE patients to rule out other conditions such as intracranial haemorrhage or space occupying lesions

References:

1. Vilstrup H et al. Hepatic encephalopathy in chronic liver disease: 2014 Practice Guideline by the American Association for the Study of Liver Diseases and the European Association for the Study of the Liver. Hepatology. 2014;60(2):715-35
2. European Association for the Study of the Liver. EASL clinical practice guidelines on the management of hepatic encephalopathy. J Hepatol. 2022 Sep;77(3):807-24.