What is the treatment for bullous impetigo?

Treatment for Bullous Impetigo

For bullous impetigo, topical mupirocin or retapamulin applied twice daily for 5 days is the first-line treatment for limited disease, while oral antibiotics are recommended for extensive disease or outbreaks. 1

First-Line Treatment Options

Limited Disease

• Topical antibiotics are the preferred initial treatment for limited bullous impetigo 1, 2, 3:
  • Mupirocin 2% ointment applied twice daily for 5 days 1, 2
  • Retapamulin 1% ointment applied twice daily for 5 days (for patients ≥9 months of age) 1, 3
• Apply a thin layer to the affected area 3
• The treated area may be covered with a sterile bandage or gauze dressing if desired 3

Extensive Disease

• Oral antibiotics are recommended for patients with numerous lesions or during outbreaks affecting multiple people 1, 4
• A 7-day course with an agent active against Staphylococcus aureus is the recommended oral regimen 1
• First-line oral options for methicillin-susceptible S. aureus (MSSA):
  • Dicloxacillin 1, 5
  • Cephalexin 1, 5

Treatment Algorithm Based on Disease Severity and MRSA Risk

For Limited Disease (Few Lesions)

1. Apply topical mupirocin or retapamulin twice daily for 5 days 1, 4
2. Monitor for clinical response within 48 hours 1
3. If no improvement, consider oral antibiotics 1, 6

For Extensive Disease or Outbreaks

1. Initiate oral antibiotics for 7 days 1, 4:
   • For MSSA: dicloxacillin or cephalexin 1, 5
   • For suspected/confirmed MRSA: doxycycline, clindamycin, or sulfamethoxazole-trimethoprim 1, 4
2. Monitor for clinical response within 24-48 hours 1
3. If progression occurs despite antibiotics, consider resistant organisms or deeper infection 1

Important Clinical Considerations

• Bullous impetigo is caused exclusively by S. aureus strains that produce toxins cleaving the dermal-epidermal junction 1, 4
• The condition presents as fragile, thin-roofed vesicopustules that may rupture, creating crusted, erythematous erosions 1, 6
• Diagnosis is typically made clinically based on characteristic appearance 1, 6
• Gram stain and culture of pus or exudates can help identify the causative organism in atypical cases 1
• The disease is generally mild and self-limited, typically resolving within 2-3 weeks without scarring 4, 6

Common Pitfalls and Caveats

• Penicillin is not effective for bullous impetigo due to high resistance rates 4, 7, 8
• Topical disinfectants are inferior to antibiotics and should not be avoided 7, 8
• Consider MRSA coverage if there is no response to first-line treatment or in areas with high MRSA prevalence 1, 4
• Monitor for increasing antibiotic resistance, particularly to mupirocin and macrolides 4, 8
• Do not confuse bullous impetigo with bullous pemphigoid, which is an autoimmune blistering disorder requiring different treatment 9, 10
• For patients with severe infection or progression despite empirical therapy, consider agents effective against MRSA 1