A neonate born to an HSV-2 seropositive mother develops vesicular skin rash, lethargy, and seizures at day 7 of life. CSF PCR for HSV is positive. The drug of choice and recommended duration of treatment is:

• A Ganciclovir IV for 14 days
• B Foscarnet IV for 14 days
• C Valacyclovir oral for 10 days
• D Acyclovir IV 20 mg/kg/dose every 8 hours for 21 days ✓

Explanation

Neonatal herpes encephalitis (disseminated or CNS disease) requires IV acyclovir at 20 mg/kg every 8 hours for 21 days per IDSA and AAP guidelines; skin-eye-mouth (SEM) disease receives 14 days. Acyclovir is phosphorylated by HSV thymidine kinase to an active form that inhibits viral DNA polymerase. Ganciclovir is used for cytomegalovirus (CMV). Foscarnet is reserved for acyclovir-resistant HSV (thymidine kinase-deficient mutants), predominantly in immunocompromised patients. Oral valacyclovir is insufficient for neonatal CNS involvement.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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