dencéphalopathie

Dencéphalopathie, or diencephalopathy, is a non-specific syndrome characterized by dysfunction of the diencephalon, including the thalamus and hypothalamus. It is not a single disease, but a pattern observed in a range of disorders that affect this brain region.

Common etiologies include metabolic or toxic disturbances (such as hypoglycemia, liver or kidney failure, severe electrolyte abnormalities, or exposure to drugs or toxins), vascular events (thalamic infarcts), infectious or inflammatory processes (encephalitis involving the diencephalon), structural lesions (tumors, hemorrhage), and less commonly demyelinating, autoimmune, prion diseases, or traumatic injury.

Pathophysiology involves disruption of diencephalic nuclei that regulate consciousness, temperature, hormonal axes, and autonomic function. Clinically, patients may present with altered mental status ranging from delirium to coma, plus autonomic instability, sleep-wake disturbances, endocrine abnormalities, and, less often, movement disorders.

Diagnosis relies on clinical suspicion supported by imaging and laboratory tests. MRI is preferred to identify diencephalic involvement; CT may be used in urgent situations. EEG, extensive metabolic workup, infectious studies, and CSF analysis may be employed to identify reversible causes and to exclude other conditions.

Management focuses on treating the underlying cause and providing supportive care. This may include metabolic correction, infection control, stroke or tumor-directed therapies, and monitoring for complications. Prognosis varies with cause and extent of injury; some cases are reversible with timely intervention, while others have a poorer outcome.

See also: encephalopathy, thalamic syndrome, hypothalamic disorders.