[The biomarker and treatment in Hashimoto's encephalopahty].

Hashimoto's encephalopathy (HE) is a treatable disease based on autoimmune mechanisms associated with Hashimoto's thyroiditis. We recently discovered the serum autoantibodies (Abs) against the NH2-terminal of alpha-enolase (NAE) as a diagnostic biomarker for HE. The serum anti-NAE Abs are not detected in normal individuals and other disorders such as infections, collagen diseases, multiple sclerosis and other autoimmune conditions. The specificity of the serum anti-NAE Abs is 91% for HE whereas the sensitivity is 50%. In our clinical study of 80 cases of HE with anti-NAE Abs, the acute encephalopathic form was the most common clinical feature, and followed by chronic psychiatric form and progressive ataxia form. The common neuropsychiatric features were consciousness disturbance, psychosis (especially delirium and hallucination), seizures and dementia. Abnormalities on EEG and decreased blood flow on SPECT were common while abnormalities on brain MRI were rare. The early diagnosis and treatment for HE could lead to good recovery from the disease. Taken together, the serum anti-NAE Abs are a useful diagnostic biomarker for HE.