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Hashimoto Encephalopathy

What is Hashimoto Encephalopathy?

Hashimoto Encephalopathy (HE) is a rare disorder that causes impaired brain function, or encephalopathy, and is associated with Hashimoto thyroiditis. The cause of HE is unknown, though research suggests there is an autoimmune component. Individuals with the disease generally respond favorably to steroid treatment.


Hashimoto Encephalopathy (HE) is a rare disorder that causes impaired brain function, or encephalopathy, and is associated with Hashimoto thyroiditis. The cause of HE is unknown, though research suggests there is an autoimmune component. Individuals with the disease generally respond favorably to steroid treatment.

Acknowledgement of Hashimoto Encephalopathy has not been added yet.

The prevalence of Hashimoto Encephalopathy is estimated to affect 2.1 per 100,000 individuals in the general population. The male to female ratio of afflicted individuals is 1:4. The average age of onset is 44. Because rare disorders are typically misdiagnosed, it is difficult to estimate the true frequency of the disease.

Synonyms for Hashimoto Encephalopathy has not been added yet.

            The exact cause of Hashimoto Encephalopathy is unknown, but researchers believe it is likely a result of an abnormal immune system. A marker for the disease is the presence of anti-thyroid antibodies and, recently discovered, anti-alpha enolase antibodies. Antibodies are molecules secreted by immune cells which normally target bacteria or viruses invading the body. But in immune system disorders, antibodies mistakenly attack the body’s own tissue, leading to inflammation.

It is unclear if the anti-thyroid antibodies are the cause or the result of Hashimoto encephalopathy, or if it is just a coincidental finding. There is no evidence to suggest that the anti-thyroid antibodies play a role in the brain damage seen in HE patients. Additionally, the level of anti-thyroid antibodies is not correlated to the severity of the disease. It is possible for HE patients to have anti-thyroid antibodies, and yet have completely normal functioning thyroid glands. At this point, the presence of anti-thyroid antibodies simply means the person’s immune system is not functioning properly.  

No genetic cause for Hashimoto Encephalopathy has been identified, and the disease is not inherited. HE can occur in people with no family history of the disorder.

The symptoms for Hashimoto Encephalopathy vary greatly person to person. Some individuals have a sudden onset of confusion with cognitive dysfunction. Other individuals have a slow progressive cognitive impairment combined with dementia, confusion and hallucinations. A rapid deterioration to coma can occur. Patients may also exhibit behavioral changes, such as depression, anxiety, social withdrawal or changes in personality.

In addition to the mental status changes, individuals may also have seizures or abnormal jerky muscle movements.  

A correct diagnosis can only be made by a medical professional. Hashimoto Disease is a diagnosis of exclusion-- meaning a whole range of other conditions need to be ruled out first. Once other diseases have been ruled out, doctors make a diagnosis for HE if the following criteria have been met:

1.     Impaired brain function with seizures, hallucinations or stroke

2.     Mild or unobservable thyroid disease

3.     Normal brain MRI

4.     Presence of anti-thyroid antibodies

5.     Absence of neuronal antibodies

6.     Reasonable exclusion of alternative causes

Diagnostic tests of Hashimoto Encephalopathy has not been added yet

Individuals with Hashimoto encephalopathy are treated with medications called corticosteroids to reduce inflammation. Affected individuals typically respond well to this treatment. The optimal dose is dependent on the individuals’ age, overall health and tolerance for medication. Individuals begin with a high dose of corticosteroid to get the disease under control, then doctors slowly lower the dose. Duration of the treatment can last a few months or up to 2 years until symptoms improve.

If a patient fails on corticosteroids, alternative immunosuppressive medications, such as azathioprine, cyclophosphamide or methotrexate, may be given. If a patient still does not respond to treatment, they then undergo plasma exchange, where the individual’s blood is removed, unwanted substances are removed, and the blood is then put back in the individual.

Anti-seizure and anti-psychotic medications are given to help relieve other symptoms if present.

Prognosis with corticosteroid treatment is generally good. Treatment may continue for a few months to up to 2 years. Relapse is possible after discontinuation of treatment. Left untreated, this condition can result in coma or death.

Tips or Suggestions of Hashimoto Encephalopathy has not been added yet.
Are there any active members on this site? Created by kimbykat
Last updated 7 Jun 2015, 12:22 AM

Posted by kimbykat
7 Jun 2015, 12:22 AM

I am part of some Facebook HE groups and just happened to find this group while doing some reading. I don't have a formal dx but I fit the "diagnostic" criteria with 10 years of elevated TPO (never in range), 10 years of abnormal EEGs showing diffuse slowing, an LP positive for protein (clean catch, no blood), and a lot of the characteristic symptoms of relapsing/remitting HE. Just wondering if this site is active?! Anyone out there?

New to HE and very confused! Created by cagles6
Last updated 27 Jan 2010, 06:00 AM

Posted by cagles6
27 Jan 2010, 06:00 AM

My 11 yr old daughter was diagnosed July 09 with HE, after 3 seizure like activities; 1 in April 09, 1 in May 09, 1 in June 09- each putting her into a coma for 3-4 days and needed to be put on a ventilator. Her diagnoses came from a Fellow at the Cleveland Clinic. In June her TSH and Microsomal antibodies levels were elevated and she went through the IVIG treatment for 5 days with another 5 day tapper of the Prednisone. Today we learned her TSH is at 5.55 and Microsomal antibodies are 808. Both of these numbers are higher than when she was diagnosed however the doctor is not going to do anything except increase her synthoid (not sure if I spelled that right) . I am very confused by this. Wondering if that is what is typically done? Or should I be looking for a different doctor? Any advise will be deeply appropriated. Thank you , Luddie

hashimoto Encefalitis Created by dusanjelic
Last updated 4 Jun 2009, 10:17 AM

Posted by Bvujaklija
4 Jun 2009, 10:17 AM

Hello, I am 55 and have been diagnosed with HE for about 4 years. I seem to have the relapsing remitting type which has given me 4 major flare ups. I am currently in the midst of the 4 th. My symptums are mostly cognitve. I get lost in familiar places, can't organize my thooughts ect. I also become incontient, have mini strokes and. Lose my balance and sometimes can't walk at all. I get jerks all over my body and drop, knock things over and throw things. I am being treated at Ohio State University Medical Center, neurology felt in Columbus, Ohio mostly with high doses of Prednisone and have started on Imuran this tar also. I am Registered Nurse working in home care (when I can work) and have done and continue to research this nasty little disease as much as I can. There is a little bit out there you just have to get on the net. If I can help in any way I will be happy to share what I know.

Posted by dusanjelic
16 Oct 2008, 07:00 PM

I m trying to find out as much as I can about this sickness , my mother in low has it for last five years and has a very slow progress and if she gets any kind of a virus as flu it takes her back so far that we all cant undersand it!she is on heavy antydepressives and on PRONISON for last 5 years and since a year ago she got major problems with urinary infekcions!I m trying to reach somebody with simular problem so we can exchange our informations and experiences in order to help eachother fighteing this teribille disase!

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Immigrated from the East, lived in the West, worked for quality of life issues thru out Latin Americas and Africa. 15 years ago, HE knocked me off my feet & got me focused on my own quality of...
Hashimotos Encelopathy
Citizen of the USA. Worried about uncle.
Mother to son who has hashimoto's encephalopathy. Health care professional.
Maybe later. I am actually seeking info for my wife, who has Hashimoto's, I just have hypothyroid as a result of treatment for Graves Disease.


Secondary Adrenal Insfficiency






Autoimmune Disease
11 Yr old Daughter with HE
I have been diagnosed with Hasimoto;s Encephalytis. I have started taking cellcept in early Sept.
trying to find some kind of therapy for my mother in low!
I have celiac disease and Graves's disease as well as serious indications of Hashimoto's Encephalopathy.



I'd like to find out more about these things.



Kit Kellison

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Are there any active members on this site?

Created by kimbykat | Last updated 7 Jun 2015, 12:22 AM

New to HE and very confused!

Created by cagles6 | Last updated 27 Jan 2010, 06:00 AM

hashimoto Encefalitis

Created by dusanjelic | Last updated 4 Jun 2009, 10:17 AM


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