[Ammonia as a cause for hepatic encephalopathy]

In a patient with cirrhosis of the liver, associated with hepatitis B virus, who was admitted for confusion and acute elevation of liver enzymes, a diagnosis of hepatic encephalopathy was made. A serum ammonia level of 54 (normal less than 33) microgram/liter, supported the diagnosis, but puzzled the medical staff regarding the possibility that ammonia may directly induce the confusion. While it is widely accepted that the ammonia level is a marker that usually parallels the amount of toxins and metabolites that bypasses the liver, its role in causing brain dysfunction is debated. However, since ammonia may directly hinder the metabolism of neuro-transmitters, and drugs and treatments specifically aimed at reducing ammonia levels may minimize the time interval for recovery from the acute brain insult, it is assumed that ammonia by itself had a role in bringing about the encephalopathy manifestations in our patients and other patients with cirrhosis of the liver.