Management

Management of leg ulcer infection in adults

The clinician should be aware that:

• there are many causes of leg ulcers:
  • underlying conditions, such as venous insufficiency and oedema, should be managed to promote healing most leg ulcers are not clinically infected but are likely to be colonised with bacteria
• antibiotics do not help to promote healing when a leg ulcer is not clinically infected

Do not take a sample for microbiological testing from a leg ulcer at initial presentation, even if it might be infected.

Antibiotics should only be offered for adults with a leg ulcer when there are symptoms or signs of infection:

• for example, redness or swelling spreading beyond the ulcer, localised warmth, increased pain or fever)
• when choosing an antibiotic take account of:
  • severity of symptoms or signs
  • risk of developing complications
  • previous antibiotic use
• oral antibiotics should be given if the person can take oral medicines, and the severity of their condition does not require intravenous antibiotics
• if intravenous antibiotics are given, review by 48 hours and consider switching to oral antibiotics if possible

Safety netting

• when prescribing antibiotics for an infected leg ulcer in adults, give advice to seek medical help if symptoms or signs of the infection worsen rapidly or significantly at any time, or do not start to improve within 2 to 3 days of starting treatment

Indications for Reassessment

• reassess an infected leg ulcer in adults if:
  • symptoms or signs of the infection worsen rapidly or significantly at any time, or do not start to improve within 2 to 3 days the person becomes systemically unwell or has severe pain out of proportion to the infection
  • when reassessing an infected leg ulcer in adults, take account of previous antibiotic use, which may have led to resistant bacteria
  • the clinician should be cognisant that it will take some time for a leg ulcer infection to resolve, with full resolution not expected until after the antibiotic course is completed
  • if symptoms or signs of the infection are worsening or have not improved as expected:
    • onsider sending a sample from the leg ulcer (after cleaning) for microbiological testing
    • when microbiological results are available:
      • review the choice of antibiotic(s) and
      • change the antibiotic(s) according to results if symptoms or signs of the infection are not improving, using a narrow-spectrum antibiotic if possible

Antibiotics for adults aged 18 years and over

First Choice antibiotic

• Flucloxacillin 500 mg to 1 g (c,d) 4 times a day for 7 days

Alternative first-choice oral antibiotics for penicillin allergy or if flucloxacillin unsuitable

• Doxycycline 200 mg on first day, then 100 mg once a day (can be increased to 200 mg daily) for 7 days in total
• Clarithromycin 500 mg twice a day for 7 days
• Erythromycin (in pregnancy) 500 mg 4 times a day for 7 days

Second-choice oral antibiotics (g guided by microbiological results when available)

• Co-amoxiclav 500/125 mg 3 times a day for 7 days OR
• Co-trimoxazole (d,e,f) (in penicillin allergy) 960 mg twice a day for 7 days

First-choice antibiotics if severely unwell (guided by microbiological results if available) (g)

Second-choice antibiotics if severely unwell (guided by microbiological results when available or following specialist advice) (g)

Antibiotics to be added if MRSA infection is suspected or confirmed (combination therapy with antibiotics listed above) (g)

Notes:

a See BNF for appropriate use and dosing in specific populations, for example, hepatic impairment, renal impairment, pregnancy and breastfeeding, and administering IV (or, when appropriate, intramuscular) antibiotics.
b Oral doses are for immediate-release medicines.
c The upper dose of 1 g 4 times a day would be off-label, as defined in the NICE glossary.
d The prescriber should follow relevant professional guidance, taking full responsibility for the decision. Informed consent should be obtained and documented. See the General Medical Council's good practice in prescribing and managing medicines and devices for further information.
e Not licensed for leg ulcer infection, so use would be off-label.
f See BNF for information on monitoring of patient parameters.
g Review IV antibiotics by 48 hours and consider switching to oral antibiotics if possible.
h See BNF for information on therapeutic drug monitoring.

Abbreviations: IV, intravenous; MRSA, meticillin-resistant Staphylococcus aureus.

Reference:

• NICE (2020). Leg ulcer infection: antimicrobial prescribing.