What is the recommended treatment for cellulitis (infection of the skin and subcutaneous tissues) in a child?

Treatment of Cellulitis in Children

For pediatric cellulitis, the recommended treatment is oral antibiotics targeting beta-hemolytic streptococci and Staphylococcus aureus, with clindamycin being the preferred first-line agent for empiric coverage of both pathogens. 1

Antibiotic Selection Algorithm

Outpatient Management (Mild to Moderate Cellulitis):

1. First-line therapy:

   • Clindamycin: 10-13 mg/kg/dose orally every 6-8 hours (to administer 40 mg/kg/day) 1
   • Provides coverage for both beta-hemolytic streptococci and community-acquired MRSA

2. Alternative options:

   • For beta-hemolytic streptococci coverage only: Oral beta-lactams (if CA-MRSA prevalence is low)

     • Amoxicillin (for skin/skin structure infections due to susceptible streptococci) 2

   • For dual coverage (streptococci + CA-MRSA):

     • TMP-SMX plus amoxicillin 1
     • Linezolid alone (for children >12 years: 600 mg twice daily; for children <12 years: 10 mg/kg/dose every 8 hours) 1

3. Important restrictions:

   • Tetracyclines (doxycycline, minocycline) should NOT be used in children <8 years of age 1

Inpatient Management (Severe Cellulitis):

1. First-line therapy:

   • Vancomycin IV (for coverage of MRSA and streptococci) 1

2. Alternative options:

   • Clindamycin IV: 10-13 mg/kg/dose every 6-8 hours (if local clindamycin resistance is <10%) 1
   • Linezolid: For children >12 years: 600 mg IV/PO twice daily; for children <12 years: 10 mg/kg/dose IV/PO every 8 hours 1

Duration of Therapy

• 5-10 days is recommended for uncomplicated cellulitis 1
• Duration should be extended if the infection is slow to resolve 1
• For streptococcal infections, minimum treatment of 10 days is recommended to prevent acute rheumatic fever 2

Management of Abscesses

• For simple abscesses: Incision and drainage alone is the primary treatment; antibiotics are not needed 1
• For complex abscesses or those with significant surrounding cellulitis: Incision and drainage plus antibiotics 1

Indications for Hospitalization

• Systemic toxicity or fever
• Rapidly progressing infection
• Significant comorbidities or immunocompromised state
• Failed outpatient therapy
• Periorbital or facial cellulitis with risk of orbital involvement
• Inability to tolerate oral antibiotics

Diagnostic Considerations

• Cellulitis is primarily a clinical diagnosis based on erythema, warmth, tenderness, and swelling 3, 4
• Blood cultures and leading edge aspirate cultures may help identify the causative organism 5
• Consider point-of-care ultrasound to rule out abscess in unclear cases 6

Monitoring and Follow-up

• Improvement should be seen within 48-72 hours of starting appropriate antibiotics
• If no improvement is observed within this timeframe, consider:
  • Alternative diagnosis
  • Need for drainage of occult abscess
  • Resistant organism requiring antibiotic change
  • Need for hospitalization for IV antibiotics

Prevention of Recurrence

• Address underlying risk factors (skin lesions, tinea pedis, chronic edema) 4
• Maintain good hygiene and keep wounds clean and covered 7
• For frequent recurrences (3-4 episodes per year), prophylactic antibiotics may be considered 7

Important Caveats

• The prevalence of CA-MRSA varies by region, with highest rates in the Southern United States 3
• Inappropriate antibiotic use contributes to rising resistance rates to agents like TMP-SMX and clindamycin 3
• Always use the narrowest spectrum antibiotic effective against the likely pathogens 3