Antibiotic treatment for diabetic foot infection

Warning

Guidance on antibiotics for the treatment of infection in the diabetic foot

Diabetic foot infection empirical antibiotic NHS Borders guideline

General

  • Inform diabetes and diabetic podiatry teams of all hospital admissions with diabetic foot infection
  • If concern re. collection, discuss with orthopaedics
  • If concern re. necrosis, discuss with vascular team
  • Check previous microbiology results before prescribing empirical antibiotics
  • Doses stated assume adult patient with normal renal and hepatic function. If renal failure/dysfunction or hepatic failure/dysfunction, seek advice
  • Consider suitability for OPAT in moderate infections or osteomyelitis – discuss with infection specialist

 

Notes

1. Requires monitoring for complications

2. Monitor serum concentration

3. Maximum 3 days then review. Switch to ciprofloxacin empirically or alternative agent based on sensitivities.

4. Fluorquinolone warning:

  • EMEA warning Nov 2018 states that fluoroquinolones should generally be avoided in patients who have previously had serious side effects with a fluoroquinolone antibiotic; use with special caution in the elderly, patients with kidney disease and organ transplant patients (due to higher risk of tendon injury).
  • Avoid concomitant use with corticosteroids.
  • Patients should be advised to stop the fluoroquinolone and seek medical advice if they experience side effects involving muscles, tendons, joints or the nervous system.
  • www.ema.europa.eu MHRA warning Nov 2018 also advices careful benefit-risk assessment in patients at risk for aortic aneurysm and dissection; patients should be advised to seek immediate medical attention in case of severe abdominal, chest or back pain.
  • www.gov.uk. These cautions should be considered if a quinolone-based regimen is necessary.

5. Ertapenem is a beta-Lactam antibacterial. Avoid if history of immediate hypersensitivity reaction to beta-lactam antibacterials.

6. Caution: 20-25% of MSSA isolated from STI/bone samples are resistant to clindamycin.

 

Abbreviations

BD = twice a day, TDS = three times a day, QDS = four times a day

MRSA = methicillin resistant Staphylococcus aureus

MSSA= methicillin sensitive Staphylococcus aureus

 

Reference

Barwell ND, Devers MC, Kennon B, Hopkinson HE, McDougall C, Young MJ et al; Scottish Diabetes Foot Action Group. Diabetic foot infection: Antibiotic therapy and good practice recommendations. Int J Clin Pract 2017 Oct 71(10). DOI: 10.1111/ijcp.13006Free full text

 

Mild infection

Symptoms
  • Pus or two or more of: erythema, warmth, pain, tenderness, induration
  • Any cellulitis <2cm around the wound confined to skin or subcutaneous tissue, and
  • No evidence of systemic infection
Treatment duration
  • Treatment with the agents shown below is recommended for 7 days, after which treatment should be reviewed and continued or discontinued as appropriate
Antibiotic naive
  • Primary - Oral Flucloxacillin1 1g QDS
  • Alternative - Oral Doxycycline 100mg BD
Not antibiotic naive
  • Primary - Oral Doxycycline 100mg BD
MRSA
  • Oral Doxycycline 100mg BD

Moderate infection

Symptoms
  • Lymphatic streaking, deep tissue infection involving subcutaneous tissue, tendon, fascia, bone or abscess
  • Cellulitis >2cm, and
  • No evidence of systemic infection
Treatment duration
  • Treatment with the agents shown below is recommended for 7 days, after which treatment should be reviewed and continued or discontinued as appropriate

  • IV antibiotics may be switched to oral preparation after an appropriate interval

Antibiotic naive
  • Primary
    • oral flucloxicillin1 1g QDS or IV 2g QDS

Add oral metronidazole 400mg TDS if anaerobes suspected

  • Alternatives
    • oral co-amoxiclav 625mg TDS, or
    • oral clindamycin6 450mg QDS or
    • IV 600mg QDS

Add oral metronidazole 400mg TDS if anaerobes suspected

Not antibiotic naive
  • Primary
    • oral co-amoxiclav 625mg TDS or IV 1.2g TDS
  • Alternatives
    • oral clindamycin6 450mg QDS + IV metronidazole 500mg TDS
    • IV vancomycin1,2 + IV metronidazole 500mg TDS
MRSA
  • Primary
    • IV vancomycin1,2 and discuss with diabetes / microbiology
  • Oral switch - Non-osteomyelitis
    • doxycyline 100mg BD

Severe infection

Symptoms
  • Any infection accompanied by systemic toxicity (fever, chills, shock, vomiting, confusion, metabolic instability). The presence of critical ischaemia of the involved limb may make the infection severe
Treatment duration
  • Treatment with the following agents is recommended for 10-14 days, after which treatment should be reviewed and continued or discontinued as appropriate
  • IV antibiotics may be switched to oral preparation after an appropriate interval
Antibiotic naive
  • Primary
    • IV flucloxacillin1 2g QDS + IV gentamicin1,2,3 + IV clindamycin4 600mg–1200mg QDS

NOTE: Oral therapy inappropriate

  • If allergic to penicillin:
    • IV vancomycin (aim for a trough vancomycin concentration of 15-20mg/L)1,2
      • + IV gentamicin1,2,3
      • + IV clindamycin6 600mg – 1200mg QDS
  • Oral switch
    • Review Microbiology results.
    • Consider broader spectrum than below based on microbiology results and patient’s progress.
      • Flucloxacillin1 1g QDS+ Clindamycin6 450mg QDS
    • Or,if allergic to penicillin Linezolid1 600mg BD
Not antibiotic naive
  • Primary
    • IV ertapenem5 1g daily + IV vancomycin (aim for a trough vancomycin concentration of 15-20mg/L)1,2
  • If allergic to penicillin:
    • IV vancomycin(aim for a trough vancomycin concentration of 15-20mg/L)1,2
      • + IV gentamicin1,2,3
      • + IV metronidazole 500mg TDS
  • Oral switch
    • Flucloxacillin 1g QDS
      • + Ciprofloxacin4 500mg (750mg if Pseudomonas isolated) BD
      • + Metronidazole 400mg TDS
    • Or, Clindamycin6 450mg QDS + Ciprofloxacin4 500mg (750mg if Pseudomonas isolated) BD
MRSA
  • Primary
    • IV vancomycin (aim for a trough vancomycin concentration of 15-20mg/L)1,2
  • Oral switch - Non-osteomyelitis
    • Doxycyline 100mg BD 

Osteomyelitis

Treatment duration
  • Treat for at least 6 weeks. Longer courses may be required. Usually at least 2 weeks of IV therapy in acute setting but oral therapy may be suitable in non-acute setting.
Antibiotic naive
  • Severe or Acute (IDSA/IWGDF-PEDIS Grade4)
    • IV Flucloxacillin 2g QDS1 + Oral Clindamycin6 450mg QDS +/- IV Gentamicin1,2,3
  • Moderate or Non-Acute (IDSA/IWGDF-PEDIS Grade 2-3)
    • Oral Flucloxacillin 1g QDS1 + Oral Clindamicin6 450mg QDS + Oral Ciprofloxacin4 750mg BD
    • Penicillin allergy
      • remove flucloxacilin from combinations above
Not antibiotic naive
  • Severe or Acute
    • IV ertapenem 1g daily + IV vancomycin (aim for a trough vancomycin concentration of 15- 20mg/L)1,2
    • Penicillin allergy
      • IV vancomycin (aim for a trough vancomycin concentration of 15- 20mg/L)1,2
      • + oral Clindamycin 450mg QDS +/- IV Gentamicin1,2,3
  • Moderate or Non-Acute
    • Oral Flucloxacillin 1g QDS + Oral Clindamycin6 450mg QDS +Oral Ciprofloxacin4 750mg BD
    • Penicillin allergy
      • remove flucloxacillin from combination above
MRSA
  • Acute
    • IV Vancomycin (aim for a trough vancomycin concentration of 15-20mg/L)1,2 + oral Rifampicin 450mg BD
  • Non-Acute
    • Usually combination therapy depending on sensitivities and infection specialist advice. 

Editorial Information

Last reviewed: 01/11/2021

Next review date: 01/11/2023

Author(s): Herlihy O.

Version: V2

Author email(s): olive.herlihy@borders.scot.nhs.uk.

Co-Author(s): Williamson R, Duguid A.

Approved By: Antimicrobial Management Team

Reviewer name(s): Herlihy O.

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