diabetic foot infection

  • CC: Diabetic foot ulcer / diabetic foot infection

  • PP: Foot pain, swelling, drainage/malodor, erythema, warmth, edema, ±fever/chills, trauma/pressure from footwear, prior ulcers/amputations, neuropathy symptoms.

  • PN: No crepitus, bullae, necrosis, rapidly progressive erythema, or systemic instability unless severe infection.

  • pertinent SHx: tobacco, EtOH, drug use

  • Etiology: Neuropathy + pressure-related skin breakdown with superimposed polymicrobial infection.

  • risk factors: Poorly controlled DM, neuropathy, PAD, prior ulcers/amputations, CKD, immunocompromised state, poor footwear/pressure injury.

  • initial DATA:

    • Vitals ± fever/tachycardia

    • WBC, BMP/Cr, glucose, ESR/CRP

    • Lactate/Bcx if septic concern

    • Wound cx after debridement

    • Foot X-ray for gas/bony changes

    • MRI if concern for osteomyelitis

    • ABI/TBI for vascular assessment

    • MRSA nares

  • pending DATA: Blood/wound cultures, MRI, vascular studies, inflammatory marker trends.

  • MEDS: Home insulin/oral DM meds, recent antibiotics, anticoagulants/antiplatelets, immunosuppressants, empiric IV antibiotics.

  • COURSE: Started on empiric IV antibiotics with wound care/podiatry involvement; evaluating for osteomyelitis; currently stable/improving.

Plan :

  • stable-> start ABX after podiatry consult for possible deep wound/tissue culture

  • unstable/ septic start Abx

  • ABX:

    • IV: ceftriaxone 2 g IV daily + metronidazole 500 mg IV q8h

    • Add vancomycin IV (pharmacy dosed, goal AUC/trough per protocol) if MRSA risk/history

    • If severe/septic/pseudomonal risk: cefepime 2 g IV q8h + metronidazole 500 mg IV q8h ± vancomycin IV

    • De-escalate per cultures

  • Step-down PO (once improving, afebrile, tolerating PO):

    • Mild:

      • cephalexin 500 mg PO QID

      • cefadroxil 500 mg PO BID

      • dicloxacillin 500 mg PO QID

    • MRSA risk:

      • doxycycline 100 mg PO BID

      • TMP-SMX DS 1–2 tabs PO BID

      • linezolid 600 mg PO BID

      • often combine doxy/TMP-SMX with amoxicillin 875 mg PO BID for strep coverage

    • Pseudomonas risk:

      • amox-clav 875/125 mg PO BID

      • levofloxacin 750 mg PO daily ± metronidazole 500 mg PO TID

    • Moderate infection:

      • amox-clav 875/125 mg PO BID + ciprofloxacin 500–750 mg PO BID

      • OR levofloxacin 750 mg PO daily + metronidazole 500 mg PO TID

  • Duration:

    • Mild SSTI: 1–2 wks

    • Moderate: 2–3 wks

    • Severe: 2–4 wks

    • Osteomyelitis: ~6 wks (shorter if fully resected)

  • podiatry consult for debridement/offloading

  • optimize glycemic control with insulin LDSS

  • Trend CBC/BMP, renal function, inflammatory markers, fever curve

  • Follow cultures; adjust antibiotics accordingly

  • Reassess in 24–48 hrs for abscess, osteomyelitis, necrotizing infection, resistant organisms, or vascular compromise if worsening

  • If septic: lactate, IVF, Bcx, broaden antibiotics

  • PT/OT as appropriate

  • Pain: acetaminophen, oxycodone PRN, gabapentin for neuropathic pain

  • f/u MRSA Nares

  • vascular surgery consult if PAD/ischemia concern

  • Continue wound care, dressing changes, debridement, and strict offloading

  • Follow-up podiatry/wound clinic in 2–4 wks; reinforce diabetic foot care/inspection