Treatment of Hashimoto Encephalitis
Hashimoto encephalitis should be treated with high-dose corticosteroids as first-line therapy, with plasmapheresis or rituximab reserved for steroid-refractory cases. 1, 2, 3, 4, 5
First-Line Treatment: Corticosteroids
- High-dose corticosteroids are the established first-line treatment for Hashimoto encephalitis, with rapid clinical improvement typically observed in responsive cases 1, 2, 5
- The condition is characterized by neurological/psychiatric symptoms, elevated anti-thyroid antibodies, and responsiveness to corticosteroid treatment 2, 5
- Prompt diagnosis and initiation of immunosuppressive treatment are critical, as symptoms respond well to therapy 5
Clinical Presentation to Recognize
- Patients may present with progressive dementia, altered consciousness, cognitive impairment, dysarthria, gait disturbance, or seizures 1, 2, 4
- The condition can mimic Creutzfeldt-Jakob disease on physical examination 1
- Key diagnostic features include: elevated thyroid antibodies, abnormal EEG, increased CSF protein, and negative microbiological testing despite encephalitic presentation 4, 5
- Presentation varies considerably and may include episodes of cerebral ischemia, seizures, psychosis, depression, or fluctuating consciousness 5
Management Algorithm for Steroid-Refractory Cases
If incomplete response to high-dose steroids:
- Consider plasmapheresis for patients who achieve sub-optimal clinical response to corticosteroids 4
- Complete remission of symptoms can be achieved when plasmapheresis is initiated after inadequate steroid response 4
For steroid-refractory cases in children/adolescents:
- Rituximab (anti-CD20 monoclonal antibody) can be valuable as second-line therapy 3
- However, careful monitoring is warranted due to risk of hypogammaglobulinemia and associated side effects 3
Critical Diagnostic Pitfalls to Avoid
- Do not delay treatment while pursuing infectious workup - negative CSF and serum microbiological testing in a patient with abnormal EEG, increased CSF protein, and elevated thyroid antibodies should prompt immediate consideration of Hashimoto encephalitis 4
- The condition presents a diagnostic conundrum since many features suggest infectious etiologies, yet treatment requires immunosuppression rather than antimicrobials 4
- Systematic anti-thyroid antibody testing is essential in patients with unexplained encephalitis 1
Natural History and Prognosis
- Some patients may experience spontaneous remission during recurrent episodes, though this is unpredictable 2
- Recognition of the condition is essential for prognosis and appropriate treatment of this rare disease 2
- The syndrome is more common in women and is associated with autoimmune anti-thyroid antibodies 5