The exact cause of the dysfunction seen in HE is not yet known.

We know that in patients with HE, “antithyroid antibodies … are the hallmark of this disease.”1  High serum (blood) antibody titers for thyroid peroxidase (TPO) or other anti-thyroid antibodies are always found in patients’ lab results. However, scientists have not yet identified the exact pathogen or mechanism by which HE causes dysfunction within a patient’s brain and central nervous system, since the anti-thyroid antibodies themselves do not cause the severe level of dysfunction seen in the disease.2

Recent research in Japan has turned up the presence of antibodies to alpha-enolase (serum autoantibodies against the NH2-terminal of a-enolase3,4,5) in addition to the presence of other anti-thyroid antibodies in the serum. At this time, research into this avenue is ongoing but limited, and very few laboratories offer testing for these autoantibodies.

Although there is no definitive diagnostic criteria for HE itself, in February of 2016 Dr. Josep Dalmau et. al published the first broadly accepted criteria for diagnosing autoimmune encephalitis in the publication, The Lancet. The article is entitled, “A clinical approach to the diagnosis of autoimmune encephalitis,”and is available for purchase online via The Lancet. This important paper written by some of the top AE experts in the world offers guidelines for the diagnosis of antibody negative autoimmune encephalopathies such as HE.



1 “Hashimoto’s Encephalopathy: Case Report and Literature Review”
Charles F. Guardia and James L. Bernat
SOJ Neurol
2014 Vol.1, No.1, pg 2.

2 Hashimoto’s encephalopathy: A rare proteiform disorder
Montagna, et al.
Journal of Pediatric Endocrinology and Metabolism Year
Available online February 3rd 2016

3 “Hashimoto’s encephalopathy as a treatable adult-onset cerebellar ataxia mimicking spinocerebellar degeneration.”
Matsunaga, Akiko, Masamichi Ikawa, Akihiro Fujii, Yasunari Nakamoto, Masaru Kuriyama, and Makoto Yoneda.
European Neurology
201 Vol.69, No.1 pg 14-20

4 [Anti-NAE autoantibodies and clinical spectrum in Hashimoto’s encephalopathy].
Matsunaga, A., and M. Yoneda.
Rinsho byori. The Japanese journal of clinical pathology
2009 Vol.57, No.3, pg 271-278.

5 [Diagnosis and treatments of Hashimoto’s encephalopathy]. (In Japanese)
Yoneda M
Rinsho Shinkeigaku = Clinical Neurology
2012, Vol.52, No.11, pg 1240-1242

Last edited by Web Team on June 20th, 2016