What is the treatment for post-varicella (chickenpox) meningitis?

Treatment of Post-Varicella Meningitis

For post-varicella (chickenpox) meningitis, intravenous aciclovir at a dose of 10-15 mg/kg three times daily is the recommended treatment, with or without a short course of corticosteroids. 1

Antiviral Therapy

• Intravenous aciclovir is the first-line treatment for VZV meningitis, with a recommended dose of 10-15 mg/kg every 8 hours 1, 2
• Since VZV is less sensitive to aciclovir than HSV, higher doses are sometimes required (up to 15 mg/kg three times daily) if renal function is normal 1, 3
• Treatment duration is typically 10-14 days, though this may be individualized based on clinical response 1, 4
• Renal function must be monitored frequently during treatment, and the dose should be adjusted accordingly in patients with impaired renal function 3

Corticosteroid Consideration

• For VZV meningitis with a vasculitic component, there is stronger evidence for adding corticosteroids to the antiviral regimen 1
• A short course of steroids (e.g., prednisolone 60-80 mg daily for 3-5 days) may be beneficial due to the inflammatory nature of the condition 1
• However, caution is needed as corticosteroids and immunosuppressive therapy increase the risk of VZV-associated meningitis 5

Treatment Duration and Monitoring

• For immunocompetent patients who show good clinical response, some evidence suggests that oral valacyclovir may be used after initial IV aciclovir therapy 2
• In immunocompromised patients, a prolonged course of intravenous aciclovir may be necessary 1
• Close monitoring for clinical improvement is essential, with particular attention to neurological symptoms 4

Special Considerations

• Age appears to be a significant factor associated with adverse outcomes in VZV CNS infections (OR 1.98 per 10-year increment) 4
• Patients receiving immunosuppressive therapy are at higher risk for VZV meningitis and may require longer treatment courses 5
• There is a risk of "rebound VZV reactivation disease" after discontinuation of antivirals, particularly in immunocompromised patients, which may warrant extended therapy 5

Treatment Algorithm

1. Confirm diagnosis through CSF PCR testing for VZV 1
2. Initiate IV aciclovir 10-15 mg/kg every 8 hours immediately 1, 3
3. Consider adding corticosteroids if vasculitic component is suspected 1
4. Ensure adequate hydration and monitor renal function 3
5. Continue treatment for at least 10-14 days 1, 4
6. For immunocompromised patients, consider extended treatment course 1, 5
7. Monitor for clinical improvement and neurological sequelae 4

Pitfalls and Caveats

• Delayed initiation of antiviral therapy may lead to worse outcomes; treatment should begin as soon as VZV meningitis is suspected 1
• Renal function must be closely monitored during aciclovir treatment, with dose adjustments as needed 3
• Mental status should be monitored during treatment due to potential neurological effects of both the disease and medication 3
• Be vigilant for rebound disease after discontinuation of antivirals, especially in immunocompromised patients 5
• Recent evidence suggests outcomes may be favorable regardless of antiviral regimen in immunocompetent patients, but IV aciclovir remains the standard of care until further studies confirm the safety of milder treatment approaches 2