[Hashimoto encephalopathy--a difficult differential diagnosis. A case report of reversible dementia and psychosis]

Hashimoto encephalopathy is a rare disease that is associated with Hashimoto thyreoiditis. Dementia, disturbances of consciousness and epileptic seizures are the most common features.

We report a case of Hashimoto encephalopathy in a 74-year-old woman who presented with psychotic episodes, visual hallucinations, dementia, tremor, rigidity and fluctuation of consciousness. After treatment with steroids, cognitive function became normal and other symptoms improved significantly.

Hashimoto encephalopathy should be considered as a differential diagnosis of psychosis in combination with dementia and other neurological symptoms to dementia with Lewy bodies and Creutzfeldt-Jakob disease.