What is the definition or description of: encephalopathy?

Altered mental state: Encephalopathy is a generalized description of an altered mental state that is caused by a medical condition. This is seen as confusion, agitation, lethargy, and/or sever somnolence. It can be caused by severe illnesses such as meningitis or other primary brain pathology. It may be seen is systemic illnesses such as sepsis. It is commonly seen in patients with cirrhosis (hepatic encephalopathy).

Generic : Encephalon means brain, pathy means abnormal, so the full term means abnormal brain. I see the statement used by many of my colleagues, but it is not a diagnosis, merely a generic expression.