What are the guidelines for treating common wound illnesses?

Guidelines for Treating Common Wound Infections

The management of wound infections requires prompt identification of the type of infection, appropriate wound care including incision and drainage when indicated, and targeted antibiotic therapy based on the severity and suspected pathogens. 1

Classification of Wound Infections

Purulent Skin and Soft Tissue Infections

• Mild: Furuncle, carbuncle, or abscess without systemic symptoms
• Moderate: Larger area of involvement with systemic symptoms
• Severe: Failed oral antibiotics, immunocompromised patient, or signs of deeper infection

Nonpurulent Skin and Soft Tissue Infections

• Mild: Typical cellulitis/erysipelas without purulence
• Moderate: Cellulitis with systemic signs of infection
• Severe: Failed oral antibiotics, systemic symptoms, or deeper infection signs

Management Principles

1. Wound Assessment and Specimen Collection

• Do:

  • Obtain appropriate specimens for culture from infected wounds before starting antibiotics 1
  • Cleanse and debride wounds before specimen collection
  • Collect tissue specimens by scraping with sterile scalpel, curettage, or biopsy from wound base
  • Aspirate purulent secretions using sterile needle and syringe
  • Send specimens promptly for aerobic and anaerobic culture

• Do Not:

  • Culture clinically uninfected wounds 1
  • Obtain specimens without first cleansing/debriding the wound
  • Rely on swab specimens, especially from inadequately debrided wounds

2. Wound Debridement and Drainage

• Abscesses and Purulent Infections:

  • Incision and drainage is the primary treatment for carbuncles, abscesses, and large furuncles 1
  • For simple abscesses without extensive cellulitis, incision and drainage alone may be sufficient

• Surgical Site Infections (SSIs):

  • Open the incision, evacuate infected material, and continue dressing changes until healing by secondary intention 1
  • Fever in first 48 hours after surgery rarely indicates SSI (consider streptococcal or clostridial infection)
  • After 4 days post-surgery, SSI becomes more likely source of fever

3. Antibiotic Therapy Guidelines

• General Principles:

  • Do not prescribe antibiotics for clinically uninfected wounds 1
  • Select empiric regimen based on infection severity and likely pathogens 1
  • Obtain cultures before starting antibiotics when possible 1
  • Base definitive therapy on culture results and clinical response 1

• Antibiotic Selection:

  • Mild infections: Target aerobic gram-positive cocci (Streptococcus, Staphylococcus)

    • Cephalexin 500 mg orally 3-4 times daily for 5-7 days 2, 3
    • For MRSA risk: Trimethoprim-sulfamethoxazole, doxycycline, or clindamycin 1

  • Moderate infections:

    • Oral therapy for outpatients: Cephalexin, amoxicillin-clavulanate, or clindamycin 2
    • Consider MRSA coverage if risk factors present

  • Severe infections:

    • Broad-spectrum empiric therapy (e.g., vancomycin plus piperacillin-tazobactam or carbapenem) 1
    • For necrotizing fasciitis: Immediate surgical consultation and broad-spectrum antibiotics 1
    • For documented group A streptococcal necrotizing fasciitis: Penicillin plus clindamycin 1

• Duration of Therapy:

  • Continue antibiotics until resolution of infection signs, not through complete wound healing 1
  • Typical duration: 5-7 days for mild infections, 7-14 days for moderate-severe infections 2

4. Special Wound Types

• Bite Wounds:

  • Primary closure not recommended except for facial wounds 1
  • Copious irrigation and cautious debridement
  • Preemptive antibiotics for high-risk bites
  • Consider tetanus prophylaxis based on immunization status

• Diabetic Foot Infections:

  • Classify by severity (mild, moderate, severe)
  • Obtain deep tissue cultures after wound cleansing/debridement 1
  • Select antibiotics based on severity and likely pathogens
  • Consider hospitalization for severe infections or moderate infections with complicating features 1

• Surgical Site Infections:

  • Open incision, evacuate infected material
  • Antibiotics typically unnecessary for minor SSIs with <5 cm erythema and minimal systemic signs
  • For more severe SSIs, select antibiotics based on surgical site and likely pathogens

Indications for Hospitalization

• Severe infections with systemic toxicity
• Suspicion of necrotizing fasciitis or gas gangrene
• Failed outpatient therapy
• Immunocompromised patients
• Inability to comply with outpatient treatment
• Diabetic foot infections with severe or moderate infection with complicating features 1

Common Pitfalls to Avoid

• Treating uninfected wounds with antibiotics
• Failing to obtain appropriate cultures before starting antibiotics
• Inadequate incision and drainage of abscesses
• Relying on antibiotics alone without appropriate wound care
• Continuing antibiotics beyond resolution of infection signs
• Delaying surgical consultation for aggressive infections
• Using broad-spectrum antibiotics when narrow-spectrum would suffice
• Failing to consider MRSA when risk factors are present

By following these evidence-based guidelines, clinicians can optimize outcomes for patients with wound infections while promoting antimicrobial stewardship.