What is the treatment for post-viral cerebritis?

Treatment of Post-Viral Cerebritis

For post-viral cerebritis, intravenous acyclovir (10mg/kg three times daily for adults or 500mg/m² three times daily for children) is the recommended first-line treatment, with consideration of corticosteroids in cases with significant inflammation or vasculitic components. 1

Diagnostic Approach

• Diagnosis should be confirmed through:

  • MRI with contrast of brain (preferred over CT)
  • CSF analysis including viral PCR, protein/glucose levels, and cell count
  • EEG to evaluate for subclinical seizures 2, 1

• Lumbar puncture can follow neuroimaging when immediately available, but should not be delayed unless specific contraindications exist 2

Treatment Algorithm

First-line Treatment

1. Antiviral Therapy

   • For HSV or VZV encephalitis:

     • Adults: Acyclovir 10mg/kg IV every 8 hours 1, 3
     • Children (3 months-12 years): Acyclovir 500mg/m² every 8 hours 2, 3
     • Treatment duration: 14-21 days 1

   • Dose adjustment required for renal impairment 3

2. Adjunctive Corticosteroids

   • Consider adding prednisolone 60-80mg daily for 3-5 days if evidence of:
     • Significant inflammation
     • Vasculitic component
     • Cerebral edema 2, 1

Special Considerations

• VZV Cerebellitis: No specific treatment needed as it's usually self-limiting 2

• Immunocompromised Patients:

  • Longer treatment course (minimum 21 days)
  • Consider broader antimicrobial coverage
  • Additional testing for opportunistic pathogens including:
    • CMV, EBV, HHV-6/7
    • Cryptococcus
    • Toxoplasma
    • Mycobacterium tuberculosis 2

• For CMV encephalitis: Consider ganciclovir, oral valganciclovir, foscarnet or cidofovir 2, 1

Monitoring and Follow-up

• Daily neurological assessment to confirm improvement 1
• Monitor renal function throughout treatment (acyclovir nephrotoxicity can affect up to 20% of patients) 1
• Consider repeat CSF PCR at end of therapy to confirm viral clearance 1
• If clinical deterioration occurs despite treatment, evaluate for:
  • Acyclovir resistance
  • Alternative diagnoses
  • Development of autoimmune encephalitis 1

Critical Care Considerations

• Patients with declining consciousness require urgent ICU assessment for:

  • Airway protection
  • Ventilatory support
  • Management of raised intracranial pressure
  • Optimization of cerebral perfusion pressure 1

• Transfer to a neurological unit is recommended if:

  • Diagnosis is not rapidly established
  • Patient fails to improve with therapy 2, 1

Important Caveats

• Acyclovir should be started empirically while awaiting test results in suspected viral encephalitis 4
• VZV is less sensitive to acyclovir than HSV, making adequate dosing crucial 1
• Oral acyclovir does not achieve adequate CSF levels for CNS infections 1
• For bacterial cerebritis, appropriate antibiotic therapy based on suspected pathogen is essential 5
• The role of steroids in HSV encephalitis remains controversial, but may be beneficial in reducing cerebral edema 2

By following this treatment algorithm, clinicians can optimize outcomes for patients with post-viral cerebritis, focusing on the primary goals of reducing mortality, morbidity, and improving quality of life.