Treatment of Hashimoto Encephalitis
The first-line treatment for Hashimoto encephalitis is high-dose corticosteroids, with plasmapheresis reserved for steroid-resistant cases.
Diagnosis Considerations
Before initiating treatment, confirm the diagnosis with:
- Elevated anti-thyroid antibodies (particularly anti-thyroid peroxidase)
- Abnormal EEG findings
- Elevated CSF protein
- Exclusion of infectious causes
- Negative microbiological testing of CSF and serum
Treatment Algorithm
First-Line Treatment
- High-dose corticosteroids:
Monitoring Response
- Assess clinical improvement within 7 days of treatment initiation 4
- Monitor:
- Mental status
- Seizure activity
- Neurological symptoms
For Steroid-Resistant Cases
If suboptimal response to high-dose steroids after 7 days:
- Initiate plasmapheresis 1, 3, 5
- Particularly effective for patients with status epilepticus not responding to steroids
Alternative Second-Line Options
- Intravenous immunoglobulin (IVIG) 3
- Consider when steroids are contraindicated or ineffective
- May be used before proceeding to plasmapheresis
Long-Term Management
Maintenance Therapy
- Low-dose prednisolone (5-10 mg/day) 6
- Consider adding immunomodulatory agents for long-term management 6
- Duration of therapy is individualized based on clinical response and relapse risk
Monitoring During Maintenance
- Monthly liver tests initially, then every 3 months once stable 4
- Monitor thyroid function
- Consider DEXA scanning at 1-2 year intervals for patients on long-term steroids 4
- Calcium and vitamin D supplementation for all patients on steroids 4
Special Considerations
Seizure Management
- Anti-epileptic drugs alone are typically ineffective for seizures in Hashimoto encephalopathy 2
- Seizures, including status epilepticus, generally respond to immunotherapy rather than conventional anti-seizure medications
Relapse Management
- For relapse after treatment withdrawal, reinstitute induction therapy followed by maintenance therapy 4
- Consider long-term maintenance therapy for patients with multiple relapses
Important Caveats
Diagnostic pitfalls: Hashimoto encephalopathy presents a diagnostic conundrum as many features mimic infectious etiologies, yet treatment is immunosuppressive 1
Treatment paradox: Despite clinical features suggesting infection (fever, leukocytosis), immunosuppression rather than antimicrobials is the appropriate treatment
Seizure management: Status epilepticus in Hashimoto encephalopathy typically responds poorly to anti-epileptic drugs but remits with steroids or other immunomodulatory therapy 2
Pediatric considerations: Children may present with acute or subacute unexplained encephalopathy and seizures, with excellent response to immunotherapy 3