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

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

CASE REPORT: 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.

CONCLUSION: 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.