A 3-year-old child with suspected viral encephalitis has CSF PCR positive for HSV-2. The MOST appropriate antiviral agent and dose is:

• A Valacyclovir 1 g orally three times daily for 14 days
• B Ganciclovir 5 mg/kg IV every 12 hours for 14 days
• C Foscarnet 90 mg/kg IV every 12 hours for 14 days
• D Acyclovir 10 mg/kg IV every 8 hours for 21 days ✓

Explanation

HSV encephalitis in children and adults is treated with IV acyclovir 10 mg/kg every 8 hours; neonatal HSV encephalitis uses the same dose but for 21 days, and post-treatment oral suppression with acyclovir is given for 6 months to prevent relapse. HSV-2 encephalitis beyond the neonatal period is less common than HSV-1 but treated identically. Valacyclovir oral bioavailability is insufficient for CNS infection. Ganciclovir is used for CMV encephalitis. Foscarnet is reserved for acyclovir-resistant HSV.

Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.