Home › Research › Risk factors
Steroid-responsive encephalopathy associated with autoimmune thyroiditis
Castillo P, Woodruff B, Caselli R, Vernino S, Lucchinetti C, Swanson J, Noseworthy J, Aksamit A et al.. Archives of neurology, 2006-02-01
Topic: Brain proteins, microglia and lab models
Background Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), often termed Hashimoto encephalopathy, is a poorly understood and often misdiagnosed entity. Objective To characterize the clinical, laboratory, and radiologic findings in patients with SREAT to potentially improve recognition of this treatable entity. Design Retrospective analysis of clinical features and diagnostic test data. Setting Two affiliated tertiary care referral institutions. Patients Twenty consecutive (6 male) patients diagnosed as having SREAT from 1995 to 2003. Main outcome measures Clinical features and ancillary test findings associated with SREAT. Results The median age at disease onset was 56 years (range, 27-84 years). The most frequent clinical features were tremor in 16 (80%), transient aphasia in 16 (80%), myoclonus in 13 (65%), gait ataxia in 13 (65%), seizures in 12 (60%), and sleep abnormalities in 11 (55%). All patients were assigned an alternative misdiagnosis at presentation, most commonly viral encephalitis (n = 5), Creutzfeldt-Jakob disease (n = 3), or a degenerative dementia (n = 4). The most frequent laboratory abnormalities were increased liver enzyme levels in 11, increased serum sensitive thyroid-stimulating hormone levels in 11, and increased erythrocyte sedimentation rate in 5. In only 5 patients (25%) did cerebrospinal fluid abnormalities suggest an inflammatory process. Magnetic resonance imaging abnormalities believed to be related to the encephalopathy were present in 5 patients (26%). Conclusions The clinical, laboratory, and radiologic findings associated with SREAT are more varied than previously reported. Misdiagnosis at presentation is common. This treatable syndrome should be considered even if the serum sensitive thyroid-stimulating hormone level and erythrocyte sedimentation rate are normal, the cerebrospinal fluid profile does not suggest an inflammatory process, and neuroimaging results are normal. Until the pathophysiologic mechanism of this and other autoimmune encephalopathies is better characterized, we believe that descriptive terms that reflect an association rather than causation are most appropriate for this syndrome.
Key findings
- Background Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), often termed Hashimoto encephalopathy, is a poorly understood and often misdiagnosed entity.
- Main outcome measures Clinical features and ancillary test findings associated with SREAT.
- Results The median age at disease onset was 56 years (range, 27-84 years).
- Conclusions The clinical, laboratory, and radiologic findings associated with SREAT are more varied than previously reported.
- This treatable syndrome should be considered even if the serum sensitive thyroid-stimulating hormone level and erythrocyte sedimentation rate are normal, the cerebrospinal fluid profile does not suggest an inflammatory process, and neuroimaging results are normal.
Why it matters
This review of 20 patients describes a treatable encephalopathy tied to autoimmune thyroiditis that is often misdiagnosed, including as degenerative dementia. Recognizing it matters because it is treatable, but this is a small retrospective case series, not a study of Alzheimer's disease itself.
New to this subject? Start with our plain-English guide: Risk factors, ranked →
Study details
- Evidence strengthLow
How this study scored 47/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Archives of neurology) |
| Journal's citation record | 3 / 4 | Archives of Neurology: journal h-index 353 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2006 — older than 20 years, still counted |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 6 / 7 | Cited 530 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 24.1 citations a year over 22 year(s) since 2006 |
| Impact for its field and year | 4 / 6 | Cited 15.3× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 2 / 4 | Cited 36 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Bradley F. Boeve: h-index 173 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Mayo Clinic: institution h-index 1,606 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 16476807) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 47 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
May need a subscription OpenAlex found no free copy of the full text (checked 6 Feb 1020), so the publisher may charge for it. The PubMed abstract is free.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Castillo, P., Woodruff, B., Caselli, R., Vernino, S., Lucchinetti, C., Swanson, J., et al. (2006). Steroid-responsive encephalopathy associated with autoimmune thyroiditis. Archives of neurology. https://doi.org/10.1001/archneur.63.2.197
Vancouver
Castillo P, Woodruff B, Caselli R, Vernino S, Lucchinetti C, Swanson J, et al. Steroid-responsive encephalopathy associated with autoimmune thyroiditis. Archives of neurology. 2006. doi:10.1001/archneur.63.2.197. PMID: 16476807.
BibTeX
@article{castillo2006-16476807,
author = {Castillo, P. and Woodruff, B. and Caselli, R. and Vernino, S. and Lucchinetti, C. and Swanson, J. and Noseworthy, J. and Aksamit, A. and others},
title = {{Steroid-responsive encephalopathy associated with autoimmune thyroiditis}},
journal = {Archives of neurology},
year = {2006},
doi = {10.1001/archneur.63.2.197},
pmid = {16476807},
url = {https://doi.org/10.1001/archneur.63.2.197}
}
Studies this one cites
Referenced by this study and also in the alzhub library, so you can read them here.