What is the treatment for Rasmussen encephalitis?

Treatment for Rasmussen Encephalitis

The treatment of Rasmussen encephalitis requires early immunomodulatory therapy with intravenous immunoglobulins (IVIG), with hemispherotomy reserved for cases with intractable seizures and progressive neurological deterioration.

Understanding Rasmussen Encephalitis

Rasmussen encephalitis (RE) is a rare but severe immune-mediated brain disorder characterized by:

• Unilateral hemispheric atrophy 1
• Progressive neurological dysfunction 1
• Intractable seizures 1
• Cognitive decline 2

First-Line Treatment: Immunomodulatory Therapy

Intravenous Immunoglobulins (IVIG)

• Early initiation of IVIG is recommended as soon as diagnosis is suspected, particularly before the appearance of motor deficits and intractable seizures 3
• Early IVIG treatment has shown to:
  • Control seizures 3
  • Reduce the rate of cerebral atrophy 3
  • Potentially prevent the need for surgical intervention 3
• Patients with only monthly to weekly seizures at the time of IVIG initiation have shown favorable outcomes without requiring surgery 3

Alternative Immunomodulatory Options

• Tacrolimus has been used as an alternative to IVIG with similar efficacy in slowing down tissue and function loss 4
• Both IVIG and tacrolimus may prevent development of intractable epilepsy 4
• Caution: Tacrolimus has been associated with serious adverse events in some patients 4

Surgical Management: Hemispherotomy

Indications for Surgery

• Intractable epilepsy despite immunomodulatory therapy 5, 2
• Progressive neurological deterioration 2
• Severe hemiparesis with daily seizures 3

Outcomes After Hemispherotomy

• 63% of surgically treated patients achieve seizure freedom 2
• 100% experience improved seizure control 2
• 90% demonstrate improved cognitive function 2
• 36% are able to discontinue antiepileptic medications 2
• 63% can taper medications 2
• Language improvement occurs in 83% of patients with dominant hemisphere disease 2
• Most patients maintain ambulatory status post-operatively 2

Timing of Surgery

• Time to surgery does not appear to significantly affect outcomes 2
• Hemispherotomy can be offered early or late in the disease course with expectations of good seizure control and functional outcomes 2
• Even patients with dominant hemisphere involvement can achieve good outcomes 2

Clinical Dilemma

• Immunotherapy may "arrest" patients in a state of pharmacoresistant epilepsy but with too good function to be offered functional hemispherotomy 4
• This creates a therapeutic challenge in determining optimal timing for surgical intervention

Management Algorithm

1. Initial Diagnosis

   • Confirm diagnosis through clinical presentation, MRI showing unilateral hemispheric atrophy, and EEG 1
   • Perform neuropsychological examination to assess cognitive function 5

2. First-Line Treatment

   • Initiate IVIG as soon as diagnosis is suspected 3
   • Monitor seizure frequency, motor function, and cerebral atrophy through serial imaging 3

3. Treatment Response Assessment

   • If good response (reduced seizures, preserved motor function): continue immunomodulatory therapy 3
   • If poor response (daily seizures, progressive hemiparesis): consider surgical evaluation 3, 2

4. Surgical Evaluation

   • For patients with dominant hemisphere involvement: perform Wada test to determine language dominance 5
   • Assess risk-benefit ratio of functional hemispherotomy based on seizure burden and functional status 2

5. Post-Treatment Monitoring

   • Regular follow-up with neuroimaging, EEG, and neuropsychological assessment 2
   • Adjust antiepileptic medications based on seizure control 2

Important Considerations

• Early diagnosis and treatment initiation are critical for better outcomes 3
• Multidisciplinary management involving neurologists, neurosurgeons, and rehabilitation specialists is essential 6
• Long-term follow-up is necessary to monitor disease progression and treatment response 2