Treatable dementia associated with Hashimoto’s encephalopathy

Treatable dementia associated with Hashimoto's encephalopathy

Makoto Yoneda

Graduate School of Nursing & Social Welfare Sciences, Fukui Prefectural University

Hashimoto's encephalopathy (HE) has been recognized as a new clinical disease based on an autoimmune mechanism associated with Hashimoto's thyroiditis, and steroid treatment is successfully administrated. HE is characterized by various neuropsychiatric symptoms, presence of anti-thyroid antibodies, high frequency of abnormalities on EEG and single photon emission tomography (SPECT) beside the normal appearance of brain MRI. The serum autoantibodies against the NH₂-terminal of α-enolase (NAE) is highly specific for HE, and helpful for the diagnosis. Patients with HE are often presented with memory impairment or delirium/hallucination similar to those in Alzheimer's disease (AD) or dementia with Lewy body (DLB), leading to be miss-diagnosed. Dementia or psychosis in HE consists of acute form (including limbic encephalitis), chronic form (leukoencephalopathy), and Creutzfeldt-Jakob disease (CJD)-mimic. We should provide an attention to the possibility of dementia or psychosis associated with HE as “a treatable dementia”.

Address correspondence to Dr. Makoto Yoneda, Faculty of Nursing & Social Welfare Sciences, Fukui Prefectural University (4-1-1 Matsuoka, Eiheiji-town Fukui 910-1195, Japan)