What is the recommended treatment for ecthyma?

Treatment of Ecthyma

For ecthyma, oral antibiotic therapy should be a 7-day regimen with an agent active against Staphylococcus aureus and streptococci, with dicloxacillin or cephalexin as first-line agents for methicillin-susceptible S. aureus, and doxycycline, clindamycin, or sulfamethoxazole-trimethoprim (SMX-TMP) when MRSA is suspected or confirmed. 1

Understanding Ecthyma

Ecthyma is a deeper skin infection than impetigo that can be caused by S. aureus, streptococci, or both. Unlike impetigo, ecthyma:

• Presents as vesicles that rupture, resulting in circular, erythematous ulcers with adherent crusts 1
• Often has surrounding erythematous edema 1
• Heals with scarring, unlike impetigo 1

It's important to differentiate ecthyma from ecthyma gangrenosum, which is a different condition typically associated with Pseudomonas aeruginosa infection in immunocompromised patients 2, 3, 4.

Diagnostic Approach

• Cultures of the vesicle fluid, pus, erosions, or ulcers should be obtained to establish the causative organism 1
• Gram stain and culture of pus are recommended to guide targeted therapy 1

Treatment Algorithm

First-line Treatment

• For presumed methicillin-susceptible S. aureus (MSSA):
  • Dicloxacillin or cephalexin for 7 days 1, 5
  • Dosing for children: 25-50 mg/kg/day divided into 4 doses 5

Alternative Treatment Options

• When MRSA is suspected or confirmed:

  • Doxycycline (avoid in children under 8 years) 1, 5
  • Clindamycin: 20-30 mg/kg/day divided into 3 doses for 7 days 1, 5
  • Sulfamethoxazole-trimethoprim (SMX-TMP): 8-12 mg/kg/day (based on trimethoprim component) divided into 2 doses 1, 5

• When streptococci alone are isolated:

  • Penicillin is the drug of choice 1
  • For penicillin-allergic patients, a macrolide or clindamycin is recommended 1

Topical Treatment Options

• Topical mupirocin can be considered for limited lesions:
  • Apply a small amount to the affected area three times daily 6
  • The area may be covered with a gauze dressing if desired 6
  • Clinical efficacy rates of mupirocin in impetigo studies were 71-93% 6
  • Patients not showing clinical response within 3-5 days should be re-evaluated 6

Duration of Treatment

• Oral antibiotic therapy should be continued for 7 days 1, 5
• The recommended duration for most bacterial skin and soft tissue infections is 7-14 days 1

Special Considerations

• Systemic antimicrobials should be used during outbreaks of poststreptococcal glomerulonephritis to eliminate nephritogenic strains of S. pyogenes 1
• In areas with high MRSA prevalence, empiric therapy should cover MRSA until culture results are available 5
• For patients with penicillin allergy, clindamycin or macrolides can be used 1, 5

Prevention of Spread

• Lesions should be kept covered with clean, dry dressings 5
• Good personal hygiene with regular handwashing is essential 5
• Avoid sharing personal items that contact the skin 5

Monitoring and Follow-up

• Clinical response should be evident within 3-5 days of starting treatment 6
• If no improvement is seen, reevaluate diagnosis and consider changing antibiotics based on culture results 1, 6