Dr Ian Hart Neuroimmunology Group Walton Centre for Neurology and Neurosurgery,
Liverpool
Hashimoto's is a rare, probably autoimmune, encephalitis/encephalopathy usually
associated with high levels of thyroid antibodies in the blood. The exact cause
is unknown - the thyroid abs are a marker rather than the cause of the problem.
Thyroid function is usually normal. Often there is a global depression of higher
function - drowsiness and sometimes coma. Other features can include amnesia and
epileptic seizures.
It is a diagnosis of exclusion and the differential is wide - from CJD to rare inborn
errors of metabolism. Useful tests include MRI brain, EEG, CSF findings, endocrine
and metabolic screens, and viral studies.
Most patients respond to high dose prednisolone, although improvement may take weeks,
even months. Plasma exchange and IVIg have been used in some patients. The prognosis
with treatment is generally good. Steroids are often continued for many months
A useful reference is
www.ncbi.nlm.nih.gov
1: Neurology. 1991 Feb;41(2 ( Pt 1)):228-33. Related Articles, Links
Hashimoto's encephalopathy: a steroid-responsive disorder associated with high anti-thyroid
antibody titers--report of 5 cases.
Shaw PJ, Walls TJ, Newman PK, Cleland PG, Cartlidge NE.
Department of Neurology, University of Newcastle upon Tyne, UK.
We describe 5 patients with a relapsing encephalopathy in association with Hashimoto's
disease and high titers of anti-thyroid antibodies. The presentation is usually
with a subacute onset of confusion, alteration in conscious level, and focal or
generalized seizures. The relapsing course, association with myoclonus or tremulousness,
and episodes of stroke-like deterioration are characteristic features. The long-term
prognosis is favorable with steroid therapy, though additional immunosuppressive
therapy may be required. Neurologic investigation typically shows a diffusely abnormal
EEG, high CSF protein level without pleocytosis, and normal brain CT and cerebral
angiogram. Isotope brain scan may show patchy abnormal uptake. Hashimoto's encephalopathy
should be recognized as a definite neurologic entity and added to the list of CNS
complications of thyroid disease.
Publication Types:
Case Reports
Review
Review of Reported Cases
PMID: 1992366 [PubMed - indexed for MEDLINE]
Last modified: May 2003