What is the treatment for a facial rash around the mouth with a yellow crust, suspected to be impetigo?

Treatment of Facial Impetigo

Topical mupirocin 2% ointment applied three times daily for 5-7 days is the first-line treatment for impetigo with a yellow crust around the mouth. 1, 2

First-Line Treatment Options

Topical Therapy (for limited lesions)

• Mupirocin 2% ointment: Apply to affected areas three times daily for 5-7 days 1, 2
  • Clinical efficacy rates of 71-93% in clinical studies 2
  • Pathogen eradication rates of 94-100% 2
  • Effective against both Staphylococcus aureus and Streptococcus pyogenes, the primary causative organisms 1
• Alternative topical options:
  • Retapamulin
  • Fusidic acid 1

When to Use Oral Antibiotics

Oral antibiotics are indicated when:

• Impetigo is extensive (multiple lesions)
• Topical therapy is impractical
• There is significant surrounding cellulitis
• Patient has systemic symptoms 3, 1

Oral Antibiotic Options:

1. First-line oral options:

   • Penicillinase-resistant semisynthetic penicillins (dicloxacillin)
   • First-generation cephalosporins (cephalexin) 1
   • Duration: 7-10 days 1

2. For penicillin-allergic patients:

   • Clindamycin
   • Macrolides (erythromycin)
   • Doxycycline (for patients >8 years old) 1

3. For suspected/confirmed MRSA:

   • Trimethoprim-sulfamethoxazole (note: inadequate streptococcal coverage)
   • Clindamycin 1

Clinical Pearls and Pitfalls

• Important distinction: Impetigo presents in two forms:

  • Nonbullous (70% of cases): Characterized by honey-colored crusts on erythematous base
  • Bullous (30% of cases): Presents with large, flaccid bullae 1, 4

• Common pitfalls to avoid:

  1. Do not use topical disinfectants as they are inferior to antibiotics 4, 5
  2. Avoid oral penicillin V as it is seldom effective for impetigo 5
  3. Do not delay treatment as impetigo is highly contagious 1
  4. Re-evaluate in 24-48 hours if using tetracyclines or trimethoprim-sulfamethoxazole to verify clinical response 1

• For pediatric patients: Mupirocin has shown excellent efficacy (78-96%) in clinical trials specifically involving children 2

Prevention and Follow-up

• Advise good hygiene practices:

  • Avoid sharing personal items
  • Limit exposure to infected individuals 1

• Complications are rare, but poststreptococcal glomerulonephritis can occur (rate <1 case/1,000 population per year) 1

• Most cases resolve within 2-3 weeks without scarring when properly treated 4

Impetigo treatment has evolved with increasing antibiotic resistance concerns, but topical mupirocin remains highly effective with minimal side effects compared to oral antibiotics 6. Clinical studies demonstrate that mupirocin is as effective as oral erythromycin with fewer systemic side effects 2, 7.