[Diagnosis and treatments of Hashimoto's encephalopathy].

Hashimoto's encephalopathy (HE), which is occasionally associated with chronic thyroiditis (Hashimoto's disease), presents with a variety of neurologic and neuropsychiatric features. We investigated the clinical features and treatments in 80 cases of HE with serum anti-NH(2)-terminal of α-enolase [anti-NAE] autoantibodies, a useful diagnostic marker of this disease. The acute encephalopathy form was the most common clinical phenotype (58%), followed by chronic psychiatric form (17%), cerebellar ataxic form (16%), and other forms such as Creutzfeltd-Jakob disease (CJD)-like form and limbic encephalitis. The common neuropsychiatric features were consciousness disturbance (66%), psychosis (53%) and dementia (38%). Involuntary movements (31%, tremor or myoclonus), seizures (31%) or ataxia (28%) occasionally occurred. Abnormalities on EEG (80%) were common while abnormalities on brain MRI were relatively rare (36%). On the treatments for HE, steroid therapy was most usually applied and successful. Intravenous immunoglobulin therapy or plasma exchange was successfully applied for the treatment of HE in some cases of HE. Taken together, we should be aware of the possibility of HE for early diagnosis and treatment of this disease.