What is the treatment for ecthyma?

Treatment of Ecthyma

For ecthyma, a 7-day regimen of oral antibiotics active against Staphylococcus aureus is the recommended treatment, unless cultures yield streptococci alone (in which case oral penicillin should be used). 1

Understanding Ecthyma

Ecthyma is a deeper form of impetigo that extends into the dermis, characterized by:

• Ulcerated lesions with adherent crusts
• Primarily caused by Staphylococcus aureus or Streptococcus pyogenes (Group A streptococcus)
• More severe than superficial impetigo

Treatment Algorithm

First-Line Treatment

1. Obtain cultures: Gram stain and culture of pus or exudates from skin lesions are recommended to guide therapy 1

2. Empiric oral antibiotic therapy (7-day course):

   • For suspected S. aureus (most common):
     • Dicloxacillin or cephalexin (for MSSA) 2
     • Doxycycline, clindamycin, or sulfamethoxazole-trimethoprim (for suspected MRSA) 2
   • If cultures confirm streptococci alone: Oral penicillin 1, 2

3. Dosing recommendations:

   • Clindamycin: 300-450 mg orally three times daily for 7 days 2
   • Complete the full 7-day course even if improvement occurs earlier 2

Special Considerations

For Ecthyma Gangrenosum

Ecthyma gangrenosum is a distinct entity, typically associated with Pseudomonas aeruginosa infection in immunocompromised patients, but can occasionally affect healthy individuals 3, 4:

• Characterized by rapidly progressing necrotic lesions with black eschar
• Requires immediate antipseudomonal antibiotics (e.g., ceftazidime, piperacillin-tazobactam) 1
• Can be fatal if not treated promptly 3

For Immunocompromised Patients

• Hospitalization and empiric antibacterial therapy with vancomycin plus antipseudomonal antibiotics (cefepime, carbapenem, or piperacillin-tazobactam) 1
• Duration of treatment: 7-14 days 1
• Consider surgical intervention for drainage of soft tissue abscess after marrow recovery 1

Monitoring and Follow-up

• Improvement should be seen within 3-4 days of starting treatment 2
• If no improvement occurs, reassess diagnosis and consider:
  • Antibiotic resistance
  • Alternative diagnoses
  • Need for surgical debridement

Prevention and Household Management

• Regular bathing and good hygiene
• Avoid sharing personal items
• Evaluate household contacts for similar infections 2

Common Pitfalls to Avoid

1. Misdiagnosis: Don't confuse ecthyma with ecthyma gangrenosum, which is a distinct entity requiring different management
2. Inadequate treatment duration: Complete the full 7-day course even if lesions appear to improve earlier
3. Failure to culture: Obtaining cultures is important to guide appropriate antibiotic therapy, especially in treatment failures or atypical presentations
4. Overlooking immunocompromise: Consider underlying immunodeficiency in patients with severe or recurrent infections

Remember that while topical antibiotics may be sufficient for impetigo, the deeper infection characteristic of ecthyma typically requires systemic antibiotic therapy.