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What is HE/SREAT?

Hashimoto’s encephalopathy (“HE”)  is a rare autoimmune disease in which an immune system malfunction  disrupts processes within the brain and nervous system, causing a variety of cognitive, neurological and/or neuropsychiatric symptoms.

It is a type of autoimmune encephalitis.

"encephalitis is inflamation of the brain."

“encephalitis is inflamation of the brain.”

The symptoms of HE/SREAT were first described in 1966 when the medical journal, The Lancet, published an article by British physicians who reported an unusual case involving a 48-year old man who presented with hypothyroidism, multiple episodes of encephalopathy, stroke-like symptoms, and Hashimoto’s thyroiditis, confirmed by elevated anti-thyroid antibodies: thyroid peroxidase antibodies (TPO)  and/or  thyroglobulin antibodies (TgAb).

In the ensuing years, physicians around the globe have continued to encounter similar patients who present with a perplexing array of symptoms that may include seizures, cognitive impairment, movement disorders, speech disturbances, ataxia, sleep disorders, and sometimes psychosis. Some cases have resulted in coma and even death.

Between 1966 and 1999, although physicians continued to encounter such patients around the world there was little published scientific research regarding the disease responsible for their symptoms. A few physicians even posited that they were really suffering from a purely psychiatric problem such as conversion disorder. Fortunately, the number of research studies looking into this poorly understood condition has escalated rapidly since 2000.

In recent years, researchers studying Hashimoto’s encephalopathy have proposed a variety of different names for the disease, including Steroid Responsive Encephalopathy Associated with Thyroiditis (“SREAT”); Encephalopathy Associated with Autoimmune Thyroid Disease (“EAATD”); and Non-vasculitic Autoimmune Inflammatory Meningoencephalitis (“NAIM”).  Others simply refer to HE using the more generic term Autoimmune Encephalopathy (“AE”), which includes an ever-growing number of autoimmune diseases characterized by cognitive impairment, psychiatric symptoms, and disruptions to the central nervous system.

Most scientists believe the name “Hashimoto’s Encephalopathy” is ill-advised since the disease is not causally related to Hashimoto’s thyroiditis (“HT”), despite the fact that HT is usually present in patients with HE.  It is this correlation that originally led to the creation of the term Hashimoto’s Encephalopathy.

Until scientists find common ground and settle on an accepted name, this website will use “HE” as a shorthand way of referring to Hashimoto’s Encephalopathy/Steroid Responsive Encephalopathy Associated with Thyroiditis (“HE/SREAT”).

HE is recognized as a rare disease by the U.S. National Institutes of Health’s Office of Rare Diseases Research, which refers to it as “Hashimoto’s encephalitis.”

[Read more here:]

Last edited by Web Team on January 25, 2019

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AE Alliance
"The Autoimmune Encephalitis Alliance promotes collaboration to improve care, find a cure and create community so that no one faces autoimmune encephalitis alone.

The Encephalitis Society
"The Encephalitis Society is an International organization providing information and support for all causes of Encephalitis."

Encephalitis Global
"Encephalitis Global is a U.S.A. 501(c)(3) non-profit organization formed in 2005 as an alliance connecting encephalitis survivors and caregivers around the world."

Scientific literature is growing at a rate of more than 2 new articles every single minute. It is impossible for scientists to consume and understand the rapidly expanding ocean of biomedical literature. You can help biomedical researchers find the information they need to discover cures faster.
"Connecting Rare Disease Patients Globally"
"Alone we are rare. Together we are strong.®"

Contact a Family
"For families with disabled children."

Madison's Foundation Provides information about rare diseases and connects parents whose children have the same rare disease.

NIH Health Hotline
Toll-free numbers from the National Library of Medicine's Health Hotlines Database.

HE Notebook - Wordpress Site
A great blog of an HE patient with a trove of information, personal stories, and links to medical studies.