Treatment of Varicella-Zoster Virus Meningoencephalitis

Introduction to Treatment

The American Academy of Neurology recommends starting aciclovir intravenously at 10 mg/kg every 8 hours immediately upon suspicion of meningoencephalitis due to Varicella-Zoster Virus, without waiting for PCR confirmation, as delayed treatment beyond 48 hours significantly worsens the prognosis 1, 2, 3

The Infectious Diseases Society of America suggests that aciclovir IV should be initiated within the first 6 hours of admission if CSF or neuroimaging results are not immediately available, or if the patient is severely ill or deteriorating 2, 3
The standard dose is 10 mg/kg IV every 8 hours in adults with normal renal function, as recommended by the Clinical Infectious Diseases journal 1, 2, 4, 3
In children aged 3 months to 12 years, use 500 mg/m² every 8 hours or alternatively 10-15 mg/kg three times a day, according to the Journal of Infection 2, 4
Do not wait for PCR confirmation before starting treatment: CSF remains PCR-positive for 7-10 days after starting aciclovir, so a late lumbar puncture can still confirm the diagnosis 2, 3

Continue aciclovir IV for 14-21 days for confirmed Varicella-Zoster Virus meningoencephalitis, as recommended by the Clinical Infectious Diseases journal 1, 2, 4, 3
Perform a control lumbar puncture upon completing treatment to confirm that the CSF is PCR-negative for Varicella-Zoster Virus 2, 3
If the CSF remains PCR-positive, continue aciclovir with weekly PCR monitoring until it becomes negative 2, 3

Varicella-Zoster Virus is less sensitive to aciclovir than HSV, so some experts recommend 15 mg/kg three times a day if renal function is normal, although most use 10 mg/kg, according to the Journal of Infection 4
The evidence for efficacy in Varicella-Zoster Virus meningoencephalitis comes mainly from case reports and small series, not controlled trials, as stated in the Clinical Infectious Diseases journal 1

Do not use corticosteroids routinely in Varicella-Zoster Virus meningoencephalitis while awaiting results from randomized controlled trials, as recommended by the Journal of Infection 4, 3
Important exception: if there is a vasculitic component or stroke-like presentation, add corticosteroids (e.g., prednisolone 60-80 mg daily for 3-5 days) due to the inflammatory nature of the lesion 4, 3

Reduce the dose of aciclovir in patients with pre-existing renal insufficiency to prevent crystaluria and obstructive nephropathy, which can affect up to 20% of patients after 4 days of IV therapy, according to the Journal of Infection 2, 3
Monitor renal function closely throughout treatment, as recommended by Praxis Medical Insights 3, 5

Patients require immediate hospitalization with access to intensive care units, as stated by Praxis Medical Insights 3
Decreased level of consciousness demands urgent evaluation in ICU for airway protection, ventilatory support, and management of elevated intracranial pressure 3, 6
EEG monitoring is essential to identify non-convulsive seizures in confused or comatose patients, according to Praxis Medical Insights 3

Use aciclovir IV 10 mg/kg every 8 hours as the preferred treatment in severely immunocompromised hosts, as recommended by Praxis Medical Insights 5
Consider temporary reduction of immunosuppressive medication in cases of disseminated or invasive disease 5

Lumbar puncture should be performed as soon as possible unless contraindicated by signs of elevated intracranial pressure, according to Praxis Medical Insights 3
PCR results in CSF should be available within 24-48 hours, as stated by Praxis Medical Insights 3
MRI is preferred over CT for neuroimaging, according to Praxis Medical Insights 3

Transfer to a specialized neurology service within 24 hours if the diagnosis is not established quickly or the patient does not improve, as recommended by Praxis Medical Insights 3
Do not discharge without a definitive or suspected diagnosis, according to Praxis Medical Insights 3
All patients require rehabilitation assessment regardless of age, as stated by Praxis Medical Insights 3
Organize outpatient follow-up with plans for continued therapy and rehabilitation, according to Praxis Medical Insights 3