[Chronic hepatic encephalopathies. Acquired cerebral degeneration not due to Wilson's disease].

We report on 4 cases of perennial hepatic encephalopathy and review similar published cases. The neurological picture consists of a cerebellar syndrome, both static and kinetic, dysarthria, choreo-athetoid abnormal movements and mental deterioration. Symptoms are permanent and usually worsen progressively. Some patients may present with a myelopathy, either isolated or combined with an encephalopathy. Relevant anatomical alterations, either encephalic or spinal, may be observed similarly in several varieties of liver disease, but in every case the role of portocaval shunts, whether spontaneous or surgically performed, appears essential. Altered results of laboratory studies, such as EEG or ammonemia, are described. Histological changes include a peculiar sort of hyperplasia of the protoplasmic astrocytes, along with a certain amount of neuronal loss. Surmised pathological mechanisms and applied therapy are briefly reviewed. For an appraisal of therapeutic results, perennial hepatic encephalopathies should be set apart from both the acute varieties and the usual chronic variety with its succession of recurrent exacerbations and remissions.