Related Subjects:
|Anti-NMDA (NMDAR) receptor encephalitis
|Herpes Simplex Encephalitis (HSV)
|Acute Encephalitis
|Limbic Encephalitis
|Paraneoplastic Limbic Encephalitis (Dementia)
|Steroid-responsive encephalopathy associated with autoimmune thyroiditis (Hashimoto's Encephalopathy)
|Acute Disseminated Encephalomyelitis
|Hashimoto's thyroiditis
|Dementias
🧠 Hashimoto's (Steroid-Responsive) Encephalopathy is a rare but completely treatable relapsing neuroendocrine disorder.
It is not directly related to thyroid hormone levels (hypothyroidism or hyperthyroidism).
High titres of anti-thyroid antibodies are usually found.
📌 Introduction
- Alternate Name: Steroid-Responsive Encephalopathy Associated with Autoimmune Thyroiditis (SREAT).
📊 Epidemiology
- ⏳ Age of Onset: Most often between 45–50 years.
- ♀️ Gender: Over 80% of cases occur in women.
⚠️ Aetiology
- 🔬 Nature: Rare autoimmune encephalitis/encephalopathy.
- 🦋 Association: Linked with autoimmune thyroiditis (e.g., Hashimoto’s thyroiditis).
- 🧪 Autoantibodies: Anti-thyroid peroxidase (anti-TPO) and sometimes anti-alpha-enolase.
🩺 Clinical Features
- 🧩 Cognitive: Confusion, memory loss, dementia-like picture, psychosis.
- 🚶 Motor: Ataxia, myoclonic jerks, seizures.
- 🦠 Endocrine: Often with goitre, though thyroid function may be normal or only mildly abnormal.
- 😴 Consciousness: Drowsiness → coma in severe cases.
🔎 Differential Diagnosis
- 🧬 CJD-like illness: Rapid cognitive decline, but CSF 14-3-3 negative in Hashimoto’s.
- 🔥 Limbic Encephalitis: Paraneoplastic or autoimmune inflammation of the limbic system.
🔬 Investigations
- 🧪 Thyroid Function Tests: Normal, hypo- or subclinical hypothyroid.
- 💉 Autoantibodies: High anti-TPO titres ± other autoimmune antibodies.
- 🧠 MRI/CT: Often normal or nonspecific (sometimes temporal lobe atrophy, worse left-sided).
- 💧 CSF: Raised protein, usually normal cells. 14-3-3 protein negative.
- 📈 EEG: Diffuse slow-wave activity, consistent with cortical dysfunction.
- 🧪 Other: Viral screens negative, angiography negative.
💊 Management
- 💉 Steroids: High-dose IV methylprednisolone or oral prednisone → usually dramatic response.
- 📉 Steroid taper + Maintenance: Azathioprine or similar agents may be used long term.
- 🔄 Alternative Therapy: Plasma exchange, IVIg, or cyclophosphamide for relapses/non-responders.
- ⚡ Seizure Management: Anticonvulsants as required.
📈 Prognosis
- 👍 Generally good if treated early.
- ⏳ Improvement may take weeks to months.
- 🔁 Relapses possible → long-term monitoring needed.
📚 References
- Chiò, A., & Palladino, R. (2014). Hashimoto's encephalopathy: A review. Frontiers in Neurology, 5, 103.
- Urey, H., & Schiller, H. (2017). SREAT: Steroid-responsive encephalopathy associated with autoimmune thyroiditis. Clinical Neurology and Neurosurgery, 157, 71-78.
- Buskila, D., Maimon, N., & Sela, E. (2015). Hashimoto's encephalopathy: A retrospective study. Neurology, 85(16), 1477-1483.
- Marino, S., & McDermott, M. (2016). Hashimoto's encephalopathy: An update. JNNP, 87(10), 1115-1121.
