Diagnostic Criteria for Metabolic Encephalopathy

Clinical Presentation

Metabolic encephalopathy presents as a spectrum of altered consciousness ranging from mild cognitive impairment to deep coma, according to the Journal of Hepatology 1
Asterixis (flapping tremor) is strongly suggestive of metabolic encephalopathy, as noted by Liver International 2, 3

Complete blood tests, including electrolytes, blood glucose, renal function, liver function tests, and complete blood count, are essential for diagnosing metabolic encephalopathy, as recommended by Liver International 2, 4
Ammonia levels, particularly for hepatic encephalopathy, should be measured, according to Liver International 4

Brain imaging, preferably MRI, is essential to exclude structural causes of altered mental status, as stated by the Journal of Hepatology and Liver International 1, 2, 3

Diabetic conditions, alcohol-related disorders, drug-induced encephalopathy, neuroinfections, electrolyte disorders, nonconvulsive epilepsy, psychiatric disorders, intracranial bleeding, stroke, organ failure, severe inflammation, dementia, traumatic brain lesions, neoplasms, normal pressure hydrocephalus, and obstructive sleep apnea must be ruled out, as listed by the Journal of Hepatology 1, 5
Uremia, hypercapnia, hypoglycemia, urea cycle defects, hypokalemia, hypomagnesemia, and hypo/hyperthyroidism are specific metabolic causes to consider, according to Liver International 2, 4

The West Haven Criteria are the gold standard for grading the severity of hepatic encephalopathy, as noted by the Journal of Hepatology 1, 6
The Glasgow Coma Scale is useful for patients with significantly altered consciousness, as stated by the Journal of Hepatology 1, 6

In patients with liver disease, uremic encephalopathy and hepatic encephalopathy may overlap, as noted by the Journal of Hepatology 1, 7
Hyponatremia and sepsis can produce encephalopathy independently and precipitate hepatic encephalopathy, according to the Journal of Hepatology 1, 7