The Alzheimer type II astrocyte is thought to be a pathological type of cell in the brain; however, its exact pathology remains unknown. Like other astrocytes, it is a non-neuronal glial cell. It's mainly seen in diseases that cause increased levels of ammonia (hyperammonemia), such as chronic liver disease and Wilson's disease. They are not associated with Alzheimer's disease, but were first described by the same neuroscientist who first described the eponymous disease, Alois Alzheimer.