Related Subjects:
|Anti-NMDA (NMDAR) receptor encephalitis
|Herpes Simplex Encephalitis (HSV)
|Acute Encephalitis
|Limbic Encephalitis
|Paraneoplastic Limbic Encephalitis (Dementia)
|Hashimoto's (Steroid responsive) Encephalopathy
|Acute Disseminated Encephalomyelitis
|Hashimoto's thyroiditis
| Dementias
A completely treatable but poorly understood relapsing neuroendocrine disorder. It does not appear to be directly related to hypothyroidism or hyperthyroidism. High levels of Anti-thyroid antibodies found.
Introduction
- Also called Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT)
Epidemiology
- Average age is 45-50 years of age and over 80% are women
Aetiology
- Rare, probably autoimmune, encephalitis/encephalopathy
- Associated with autoimmune thyroiditis
- Autoantibodies to alpha-enolase
Clinical
- Global depression of higher function
- Dementia, psychosis, ataxia, Goitre
- Drowsiness and sometimes coma
- Amnesia and seizures and myoclonic jerks
Differential
- CJD-like clinical picture
- See Limbic Encephalitis
Investigations
- TFTS: May be normal, hypothyroid, subclinical hypothyroid
- High titres of Thyroid anti-thyroid peroxidase (anti-TPO) antibody. May be anti parietal and other autoimmune disease antibodies
- MRI brain often normal or non-specific
- CSF findings may be normal/protein may be elevated
- EEG showed diffuse slow-wave pattern
- Endocrine and metabolic screens, and viral studies.
- CSF : 14-3-3 negative
- Angiography: negative
Management
- Most patients respond to high dose steroids and then oral azathioprine with tapering of steroid dose.
- People with repeated HE relapses, do not respond to steroids, and/or cannot tolerate steroid treatment have been treated with other immunosuppressive medications such as azathioprine and cyclophosphamide. In some patients, Plasma exchange and IVIg have been used.
- Anticonvulsants may be needed acutely. Improvement may take weeks, even months. Prognosis with treatment is generally good.