Diabetic Foot Infection

Diabetic Foot Infection


  • Do not culture uninfected ulcers, they will always grow bugs
  • Please avoid swabbing wounds and/or drainage with cotton swabs (especially non-debrided and non-cleansed wounds)
  • Appropriate cultures can be highly impactful to patient outcomes

To obtain useful diabetic ulcer culture:

  1. Cleanse +/- debride the wound
  2. Obtain tissue by biopsy or curettage from ulcer base
  • Most useful for chronic infection, recent abx, suspected MDRO
  • Mild/superficial infection usually mono-microbial and predictably gram+ staph or strep if no recent abx (within the last month)
  • Consider gram-negative organisms if recent abx or chronic wound, necrosis or gangrene
  • MRSA is prevalent at AHT (~60% of staph aureus is MRSA)
    • Specific risk factors are history of MRSA infection/colonization in past year, nursing home/subacute facility stay, recent or current prolonged hospital stay, IVDU, clinically severe infection
  • Pseudomonas can often be a non-pathogenic colonizer and even when isolated patients often improve on abx ineffective against pseudomonas (ertapenem was = pip/tazo in DFI with pseudomonas on culture)
    • Specific risk factors are foot soaking, hot tubs, whirlpool, chronic wound with prolonged abx exposure, failed non-pseudomonal abx, clinically severe infection
  • Anaerobes are considered not a major pathogen in most mild-mod DFI
    • Specific risk factors are “dead meat”, necrotic tissue, gangrene, putrid discharge, clinically severe infection

Change to oral antibiotics once patient is stable

Indication by Severity