Diagnosis
Investigations
The diagnosis of hepatic encephalopathy can only be made in the presence of confirmed liver disease (types A and C) or a portosystemic shunt (type B), as its symptoms are similar to those encountered in other encephalopathies. To make the distinction, abnormal liver function tests and/or ultrasound suggesting liver disease are required, and ideally a liver biopsy. The symptoms of hepatic encephalopathy may also arise from other conditions, such as bleeding in the brain and seizures (both of which are more common in chronic liver disease). A CT scan of the brain may be required to exclude bleeding in the brain, and if seizure activity is suspected an electroencephalograph (EEG) study may be performed. Rarer mimics of encephalopathy are meningitis, encephalitis, Wernickes encephalopathy and Wilsons disease; these may be suspected on clinical grounds and confirmed with investigations.The diagnosis of hepatic encephalopathy is a clinical one, once other causes for confusion or coma have been excluded; no test fully diagnoses or excludes it. Serum ammonia levels are elevated in 90% of people, but not all hyperammonaemia (high ammonia levels in the blood) is associated with encephalopathy. A CT scan of the brain usually shows no abnormality except in stage IV encephalopathy, when brain swelling (cerebral oedema) may be visible. Other neuroimaging modalities, such as magnetic resonance imaging (MRI), are not currently regarded as useful, although they may show abnormalities.
See also
List of cutaneous conditions

References


== External links ==