What is the best course of treatment for a 1-year-old patient with varicella (chickenpox) infection and leukocytosis (elevated White Blood Cell (WBC) count)?

Management of Varicella in a 1-Year-Old with Leukocytosis

For an otherwise healthy 1-year-old with varicella and elevated WBC, supportive care is the primary treatment, with close monitoring for bacterial superinfection being the critical priority, as antiviral therapy is not routinely indicated in immunocompetent infants with uncomplicated varicella. 1

Primary Treatment Approach

Supportive Care as First-Line Management

• Supportive care remains the cornerstone of treatment for immunocompetent infants with varicella, as antiviral therapy with acyclovir is not routinely recommended in this population. 1
• Lukewarm baths with colloidal oatmeal should be used to relieve itching and maintain skin hygiene. 2
• Adequate hydration and nutrition must be maintained throughout the illness course. 3

When Antiviral Therapy IS Indicated

• Oral acyclovir (20 mg/kg per dose, 4 times daily for 5 days, maximum 800 mg per dose) should be initiated if the child is immunocompromised or receiving immunosuppressive therapy. 1, 4
• Intravenous acyclovir is specifically indicated for immunocompromised patients with varicella-zoster infections. 4
• Antiviral therapy is most effective when initiated within 24 hours of rash onset, with uncertain efficacy beyond this window. 4

Critical Concern: Elevated WBC and Bacterial Superinfection Risk

Understanding the Leukocytosis

• The elevated WBC count in this 1-year-old is a red flag for potential bacterial superinfection, which represents the most common and serious complication of varicella in children. 5, 6
• Bacterial skin and soft tissue infections, particularly invasive group A streptococcal infections, are the most frequent complications requiring hospitalization in varicella patients. 5
• Infants under 1 year are 6 times more likely to be hospitalized than children aged 5-9 years due to higher complication rates. 5, 2

Specific Clinical Monitoring Required

• Monitor for persistence or recurrence of fever ≥38.5°C for ≥3 days after varicella onset, as this is independently associated with an 8-fold increased risk of severe bacterial superinfection. 7
• Examine for signs of invasive bacterial infection including: expanding erythema around lesions, purulent drainage, increasing pain or tenderness, and systemic toxicity. 5, 8
• Watch for pneumonia, dehydration, and encephalitis as additional serious complications. 5

Critical Medication Pitfall to Avoid

NSAIDs Are Contraindicated

• Never use ibuprofen or other NSAIDs for fever management in varicella, as this increases the risk of bacterial complications 4-fold and increases surgical intervention necessity by nearly 3-fold. 8, 7
• Use acetaminophen for fever control if needed, avoiding aspirin due to Reye syndrome risk. 5, 2
• The association between NSAIDs and severe bacterial superinfections (adjusted OR=4.8) has been consistently demonstrated in multiple studies. 7

Isolation and Infection Control

Preventing Transmission

• Isolate the child until all lesions have crusted over, typically 5-7 days from rash onset. 1
• Household contacts who are susceptible and have been exposed may benefit from varicella vaccine if administered within 3-5 days of exposure (>90% effective within 3 days, 70% effective within 5 days). 2
• Varicella-zoster immune globulin (VZIG) should be considered for high-risk exposed individuals without immunity, including immunocompromised contacts, pregnant women without evidence of immunity, and specific neonatal populations. 5, 2

When to Escalate Care

Indications for Immediate Medical Re-evaluation

• Development of any of the following warrants urgent reassessment: persistent fever beyond 3 days, signs of bacterial superinfection, respiratory distress suggesting pneumonia, altered mental status, severe dehydration, or hemorrhagic lesions. 5, 8, 9
• Group A Streptococcus infection increases the need for surgical intervention by 7.5-fold and requires aggressive antibiotic therapy. 8
• Approximately 29% of hospitalized children with bacterial complications of varicella have transient complications after treatment, emphasizing the need for close follow-up. 8

Future Prevention

Post-Recovery Vaccination

• Once the child fully recovers from varicella, no additional varicella vaccination is needed, as natural infection provides lifelong immunity. 1
• If the child had not yet received the first dose of varicella vaccine (normally given at 12-15 months), vaccination is no longer necessary after natural infection. 5, 1