IDSA Recommendations for Diabetic Foot Skin/Soft Tissue Infections
The IDSA/IWGDF recommends treating diabetic foot skin and soft tissue infections with systemic antibiotics for 1-2 weeks for most infections, with specific regimens based on infection severity and likely pathogens. 1
Classification and Diagnosis
Infection Classification
- Mild: Affects only skin/superficial subcutaneous tissue
- Moderate: Involves deeper tissues, may have systemic manifestations
- Severe: Accompanied by systemic inflammatory response syndrome 1
Diagnostic Approach
- Diagnose infection based on presence of ≥2 classic signs of inflammation (erythema, warmth, tenderness, pain, induration) or purulent secretions 1
- For diagnostically equivocal cases, assess inflammatory biomarkers:
- C-reactive protein (CRP)
- Erythrocyte sedimentation rate (ESR)
- Procalcitonin (PCT) 1
- Do not use foot temperature or quantitative microbial analysis for diagnosis 1
Microbiological Assessment
- Obtain cultures from suspected infected wounds before starting antibiotics when possible 1
- Use conventional (not molecular) microbiology techniques for pathogen identification 1
- For suspected osteomyelitis, obtain bone (not soft tissue) samples for culture 1
Treatment Recommendations
General Principles
- Do not treat clinically uninfected foot ulcers with antibiotics 1
- Consider hospitalization for:
- All severe infections
- Moderate infections with relevant comorbidities 1
Antibiotic Selection
Empiric Therapy Based on Severity:
Mild Infections:
- Oral therapy targeting aerobic gram-positive cocci
- Options: amoxicillin-clavulanate, first-generation cephalosporin 2
Moderate Infections:
- Broader coverage including gram-negative organisms
- Options: amoxicillin-clavulanate, levofloxacin with/without clindamycin, ceftriaxone with/without metronidazole 2
Severe Infections:
- Initial parenteral therapy with broad-spectrum coverage
- Options: vancomycin + piperacillin-tazobactam, vancomycin + imipenem-cilastatin 2
Special Considerations
MRSA coverage: Add if patient has history of MRSA, high local prevalence, or severe infection
- Options: vancomycin IV, linezolid, daptomycin 2
Pseudomonas coverage: Consider for patients with:
Anaerobic coverage: Include for:
- Necrotic wounds
- Gangrenous tissue
- Ischemic limb
- Deep, chronic wounds 2
Treatment Duration
Soft tissue infections:
Osteomyelitis: 4-6 weeks 2
Re-evaluation: If infection has not resolved after 4 weeks of appropriate therapy, re-evaluate and consider further diagnostic studies or alternative treatments 1
Surgical Management
- Debride any wound with necrotic tissue or surrounding callus 1
- Surgical interventions range from minor to extensive debridement 1
- For severe infections ("diabetic foot attack"), urgent surgical intervention with radical debridement is required 3
Wound Care
- Proper wound care is essential alongside antibiotic therapy 2
- Components include:
- Thorough cleaning and debridement
- Removal of foreign bodies/devitalized tissue
- Appropriate dressing based on wound characteristics
- Offloading pressure 2
Multidisciplinary Approach
- Provide a well-coordinated approach by specialists in various fields, preferably through a multidisciplinary diabetic foot care team 1
- Evaluate the affected limb for:
- Arterial ischemia
- Venous insufficiency
- Protective sensation
- Biomechanical problems 1
Monitoring and Follow-up
- Re-evaluate within 48-72 hours to assess response 2
- Adjust therapy based on culture results and clinical response 2
- Change antibiotics if no improvement after 48-72 hours 2
Recent evidence suggests that for moderate to severe soft tissue infections (without osteomyelitis), a 10-day course of antibiotics after debridement may be as effective as a 20-day course, with similar remission rates and adverse events 4, though larger confirmatory trials are still needed.