Patient handout

Neonatal HSV (SEM, CNS, disseminated forms) — empiric acyclovir + form-specific duration

PRODUCTION

1. Your condition

This handout is for neonatal hsv (sem, cns, disseminated forms) — empiric acyclovir + form-specific duration. Your care team identified this based on: vesicular skin / mucous-membrane lesions in a neonate ≤ 28 d (kimberlin pediatrics 2013 pmid 23359576; aap red book 2024).

Other reasons your team may use this plan: seizures (often subtle — lip smacking, eye deviation, bicycling) in a neonate ≤ 28 d with no other clear cause (kimberlin pediatrics 2001 pmid 11483782); hypothermia (t < 36 °c) or unexplained encephalopathy / abnormal tone / lethargy / poor feeding in a neonate ≤ 28 d (aap red book 2024; hsv mimics sepsis); ast/alt 2-10× uln in a neonate ≤ 28 d — suspect disseminated hsv (kimberlin pediatrics 2013 pmid 23359576).

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

Medication	Starting dose	How	When	What it does
acyclovir	60 mg/kg/day divided q8h IV (20 mg/kg/dose) for term ≥ 35 wk; q12h if preterm < 35 wk	IV	q8h (q12h preterm)	Kimberlin Pediatrics 2001 PMID 11483782 — high-dose 60 mg/kg/d superior to historical 45 mg/kg/d for outcome; 14 d duration for SEM form (no CSF pleocytosis + no disseminated features)

Plan: Neonatal HSV acyclovir regimen — by form (SEM / CNS / disseminated) + duration + suppression

3. When to call your provider

Contact your care team if any of the following happen:

New vesicles / seizures / encephalopathy / hypothermia → urgent peds / ED + acute re-treatment
New focal neurological signs OR new seizures → urgent neuro + neuroimaging + EEG
Hearing loss confirmed on audiology → ENT + audiology + speech + early intervention
Family caregiver PHQ-9 ≥ 15 OR EPDS elevated → mental-health urgent referral
Suspected immunodeficiency (≥ 2 serious infections in 12 mo OR unusual pathogen recurrence) → clinical immunology referral
Suppression neutropenia (ANC < 500) → hold suppression + ID consult; resume after recovery (Kimberlin NEJM 2011 PMID 21991950)

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

Vesicular skin or mucous-membrane lesions (mouth / conjunctivae / scalp) in a neonate ≤ 28 d — empiric IV acyclovir 60 mg/kg/d divided q8h within 1 h + HSV PCR (CSF + blood + surface swabs) + admit + close monitor (Kimberlin Pediatrics 2013 PMID 23359576; AAP Red Book 2024)(life-threatening)
New-onset neonatal seizures (often subtle — lip smacking, eye deviation, bicycling) in a ≤ 28 d neonate with no clear bacterial / metabolic / structural cause — empiric acyclovir + LP for CSF + HSV PCR + EEG; routes to peds.status_epilepticus.v1 if status epilepticus evolves (Kimberlin Pediatrics 2001 PMID 11483782)(life-threatening)
Hypothermia (T < 36 °C) OR unexplained encephalopathy / abnormal tone / lethargy / poor feeding in a neonate ≤ 28 d — empiric acyclovir + sepsis workup + bacterial co-empirics; do NOT defer for culture results (AAP Red Book 2024; HSV mimics sepsis)(life-threatening)
AST/ALT 2-10× ULN in a neonate ≤ 28 d — suspect disseminated HSV; full HSV workup + empiric acyclovir + serial AST/ALT + consider hepatic ultrasound; differential includes ischemic hepatopathy and metabolic disease (Kimberlin Pediatrics 2013 PMID 23359576)
Disseminated HSV features in neonate ≤ 28 d — sepsis-like + DIC (prolonged PT/PTT, low fibrinogen, high D-dimer, low platelets) + hepatic (AST/ALT 2-10× ULN) + hypothermia + multi-organ failure → ICU + acyclovir + bacterial co-empirics + supportive (cryoprecipitate + FFP + platelets); mortality ~ 30% even with treatment; routes to id.sepsis.peds.v1 + id.neonatal-sepsis.early-late.v1 with dual coverage (AAP Red Book 2024; Kimberlin NEJM 2011)(life-threatening)
CSF lymphocytic pleocytosis ≥ 5 WBC/µL + elevated protein (often 100-500 mg/dL) + normal-low glucose + HSV PCR positive OR strong clinical suspicion in neonate ≤ 28 d → 21 d acyclovir IV + 6 mo oral suppression per Kimberlin 2011 PMID 21991950 (Kimberlin Pediatrics 2001 PMID 11483782)(life-threatening)
Maternal active genital HSV lesions at delivery — primary infection (30-50% transmission) OR recurrent infection (2-5% transmission); C-section indicated if active lesions; consider neonatal prophylactic acyclovir × 10 d for maternal primary HSV with delivery within 4 wk of seroconversion per local protocol (ACOG Practice Bulletin 220 2020; Kimberlin Pediatrics 2013 PMID 23359576)
Neonate completed 21 d IV acyclovir for CNS or disseminated form → transition to oral acyclovir suppression 300 mg/m² PO TID × 6 months per Kimberlin NEJM 2011 PMID 21991950 (neurodev outcome benefit at 12 mo + recurrence reduction ~ 50%)
Recurrent SEM disease after completed acute treatment course — ~ 50% of treated infants by 12 mo (especially HSV-2) → re-treat acute (14 d IV acyclovir) + extend suppression duration per ID consult; ocular recurrence → topical trifluridine + systemic acyclovir; do not skip systemic for ocular-only (Kimberlin Pediatrics 2013 PMID 23359576)

5. Follow-up

Oral acyclovir suppression 300 mg/m² PO TID × 6 months for CNS or disseminated forms (Kimberlin NEJM 2011 PMID 21991950 — neurodev outcome benefit). Monthly CBC on suppression (neutropenia ~ 5-10%). Developmental peds + neurology + ophthalmology + audiology at 6, 12, 24 mo. Recurrence surveillance — ~ 50% of treated infants have skin recurrence by 12 mo; re-treat acute (14 d IV) + extend suppression. Family education for return precautions (new vesicles, neuro signs, hypothermia). Lifelong suppression-decision counseling.

6. Sources

Guideline: AAP Red Book current edition (2024 + 2026 floor) — Neonatal HSV chapter + Kimberlin NEJM 2011 high-dose acyclovir PMID 11483782 + Kimberlin NEJM 2011 suppression companion PMID 21991950 + Kimberlin Pediatrics 2013 management overview PMID 23359576 + ACOG Practice Bulletin 220 (2020) Management of Genital Herpes in Pregnancy + NICE NG195 (2021) + NIAID Collaborative Antiviral Study Group (CASG) historical RCTs