Review of the final report of the 1998 Working Party on definition, nomenclature and diagnosis of hepatic encephalopathy.

Hepatic encephalopathy (HE) is a heterogeneous disease that develops as a result of serious liver disease, such as in fulminant hepatitis or cirrhosis, or a portosystemic shunt. It manifests as a spectrum of abnormalities involving cognition, attention, functional ability, personality and intellect. The neuropsychiatric impairment associated with HE can range from mild alteration of cognition and consciousness to coma, depending on the stage of the illness. In 1998, the World Gastroenterology Organization formed a working party to develop guidelines and recommendations for the diagnosis, grading and treatment of HE for research and practice. In this report, we discuss the various tests available for diagnosis and grading and the recommendations of the working party, which provide a framework for further studies on clinical trial methodology.