Diabetic Foot Infection, Severe
Severe diabetic foot infection is defined as:
Local foot infection (as indicated by 2 or more of the following):
- local swelling or induration
- erythema (more than 2cm around ulcer)
- local tenderness or pain
- local warmth
- purulent discharge
WITH signs of sepsis/ systemic inflammatory response syndrome (SIRS) - see also guideline Sepsis Identification and Management
Particular attention should be paid to the potential need for surgery (source control)
- It is essential that cases of diabetic foot infection are managed in conjunction with Podiatry, Orthopaedic Surgery and Micro/ID.
- An assessment of vascular sufficiency should be performed.
Cases are typically commenced on broad spectrum intravenous antibiotics.
A wound sample should be taken prior to/as soon as possible after starting antibiotics. Superficial swabs have limited diagnostic value, so preference should be made for a deep swab, collection of pus, tissue sample (by an appropriately trained clinician) or surgical cultures.
Risk factors for Pseudomonas include: previous isolation of Pseudomonas from wound swab or tissue; recent/frequent exposure to broad spectrum antibiotics.
Preferred
If NO risk factors for Pseudomonas:
co-amoxiclav 1.2g iv tds
If haemodynamically unstable: ADD gentamicin 5mg/kg iv single dose. See gentamicin monograph for dosing (including renal dosing).
If risk factors for Pseudomonas:
piperacillin-tazobactam 4.5g iv tds
If haemodynamically unstable: ADD gentamicin 5mg/kg iv single dose. See gentamicin monograph for dosing (including renal dosing).
Alternative
For penicillin allergy (non-severe, severe):
If no risk factors for Pseudomonas:
co-trimoxazole 960mg po bd + metronidazole 400mg po tds
If haemodynamically unstable: ADD gentamicin 5mg/kg iv single dose. See gentamicin monograph for dosing (including renal dosing).
For MRSA positive patients: No additional antibiotics required
If risk factors for Pseudomonas:
ciprofloxacin* 500mg po bd (400mg iv bd) + clindamycin 450mg po/iv tds
If haemodynamically unstable: ADD gentamicin 5mg/kg iv single dose. See gentamicin monograph for dosing (including renal dosing).
For MRSA positive patients: ADD iv vancomycin
*Ensure that the patient is given the Fluoroquinolone MHRA patient information leaflet. Fluoroquinolones, including ciprofloxacin are associated with disabling and potentially long-lasting or irreversible side effects. See Fluoroquinolone antibiotics - severe adverse effects.