Diabetic foot ulcer – the importance of recognising and managing infection

Image showing two nurses exchanging medical information.

Diabetes affects about 422 million people worldwide, with steadily increasing numbers over the past few decades.1 It affects the heart, eyes, kidneys, nerves, and blood vessels. Peripheral neuropathy and peripheral artery disease (PAD) are the leading causes of diabetic foot disease – one of the most severe complications of diabetes mellitus.2

Development of diabetic foot ulcers

Diabetic foot ulcers can have many causes. However, peripheral neuropathy and peripheral arterial disease (PAD) are among the most common risk factors.
Neuropathy impairs sensitivity, causing abnormal loading of the foot. This results in thickened skin, also called callus formation. Callus formation increases pressure on the underlying tissue, causing skin breakdown and ulceration.
PAD occurs in up to 50% of patients with diabetic foot ulcers and is mainly caused by atherosclerosis.2 It impairs the blood flow and causes ischemia, which negatively affects wound healing.
The majority of diabetic foot ulcers either result solely from peripheral neuropathy (purely neuropathic) or a combination of neuropathy and ischemia caused by PAD (neuro-ischemic). Minor foot trauma or poorly fitting shoes can also cause ulcerations in diabetic patients.2

How diabetes affects wound healing

Limb ischemia due to peripheral artery disease increases the risk of a diabetic foot ulcer becoming infected and impairs the treatment outcome. The presence of clinically significant foot ischemia makes both diagnosis and treatment of infection considerably more difficult.3 Even minor foot problems need to be taken seriously, as patients with diabetes are more likely to experience complications or require amputation.2

Image showing a diabetic foot ulcer

Infected diabetic foot ulcer after amputation

Signs of infected diabetic foot ulcers

The increasing prevalence of diabetes leads to a rising number of foot complications, including infections.5 Foot infections are the main reasons for hospitalisation in diabetic patients. The typical signs and symptoms of infection are often absent in patients with diabetes caused by peripheral neuropathy and peripheral artery disease.3 Every patient with diabetes and an active diabetic foot ulcer should be assessed by a multidisciplinary team, including diabetes and wound nurses, general practitioner, diabetologist, and vascular consultant, among others.2

Diabetic foot infection is identified if at least two of the following signs are present3:

  • Local swelling or induration
  • Erythema of more than 0.5 cm around the wound (refers also to any part of the foot, not just of a wound or an ulcer)
  • Local tenderness or pain
  • Local increased warmth
  • Purulent discharge

Patients with a diabetic foot ulcer are at risk of osteomyelitis.


In people with dark skin tones be aware of the signs and symptoms of infection that do not soley rely on redness 4


Other causes of an inflammatory process of the skin—such as trauma, gout, acute Charcot neuro-osteoarthropathy, fracture, thrombosis, or venous stasis—must be ruled out for the diagnosis of an infected diabetic foot ulcer.3
Patients with diabetes are prone to spreading infections to fascia, tendons, muscles, joints and bones, which are also fostered by the anatomy of the foot. Severely infected diabetic foot ulcers and moderately infected diabetic foot ulcers that are complex or associated with key relevant morbidities require immediate hospitalisation for urgent systemic antibiotic therapy, including surgical intervention in many cases. The typical signs of systemic infection—for example fever, chills, elevated leucocytes, or significant metabolic disturbances—are often absent in diabetic patients. Therefore, an experienced team of healthcare professionals is required to rule out this potentially life-threatening complication.3

Treatment pathway for diabetic foot infection

The treatment of diabetic foot infection requires a multidisciplinary approach: wound specialists and clinicians have to collaborate closely. Regular assessment of the ulcer is vital to evaluate if a surgical consultation or hospitalisation and systemic antibiotics are needed. 2 The following steps provide an overview of wound care in diabetic foot infection.2, 6*

  • Complete a holistic wound assessment.
  • Consider the need to cleanse and debride.
    - The assessment for debridement may require a specialist referral.
    Cutimed® DebriClean can be considered for wounds that require mechanical debridement.
  • Select dressings appropiate to manage exudate and maintaining a moist environment.
    - Consider a dressing with a physical mode of action like Cutimed® Sorbact®. It supports infection management and reduces bioburden in wounds. It does not contain an active antimicrobial agent and thus avoids the risk of resistant bacterial strains.
  • Do not soak the feet, as this may induce skin maceration.
  • Reassess the wound in regular intervals.
  • Reassess the need for in-hospital treatment, surgical intervention, or antibiotic treatment.
  • Rule out spreading or systemic infection and seek urgent specialist assessment, if required.

Additionally, optimise the management of diabetes, and improve tissue perforation, nutritional status, and other potential comorbidities.

Instruct patients (and relatives or caregivers) on appropriate foot ulcer self-care and how to recognise and report signs and symptoms of new or worsening infection (e.g., onset of fever, changes in local wound conditions, and worsening hyperglycemia).

Take-home messages

  • Even minor foot trauma or poorly fitting shoes can cause foot ulcers in patients with diabetes.
  • The presence of peripheral neuropathy and peripheral artery disease can alter and mask the typical infection signs in patients with diabetes.
  • Local infection in diabetic foot ulcers can present with local swelling, erythema, tenderness or pain, increased warmth, or purulent discharge.
  • Identifying infection in people with dark skin tones by investigating signs and symptoms that do not reply on redness.
  • Patients with diabetes are prone to spreading infections, which are also fostered by the anatomy of the foot. In case of suspected infection, an experienced team of healthcare professionals is required to rule out this potentially life-threatening complication.
  • Early detection of infection and early referral or consultation with specialists are essential.
  • The close collaboration of wounds specialists and clinicians is required to manage locally infected diabetic foot ulcers.
  • Proper care for locally infected diabetic foot ulcers requires a good wound assessment, wound management with cleansing, debridement and infection management.
  • Dressings with a physical mode of action, such as Cutimed® Sorbact®, support infection management and reduce bioburden in wounds.
  • Bring awareness to patients and relatives on appropriate foot ulcer self-care and how to recognise and report signs and symptoms of infection.


*This article is intended to be used as an information guide to be considered when the organisation makes clinical decisions and does not constitute medical advice. For detailed device information, including indications for use, contraindications, effects, precautions, and warnings, please consult the product’s Instructions for Use (IFU) before use. In case of doubt please consult a healthcare professional.


  1. Diabetes. WHO. 2022; accessed on November 4, 2022. Read more
  2. Schaper NC et al. Practical Guidelines on the prevention and management of diabetic foot disease (IWGDF 2019 update). Diabetes Metab Res Rev. 2020;36 Suppl 1:e3266.
  3. Lipsky BA et al. Guidelines on the diagnosis and treatment of foot infection in persons with diabetes (IWGDF 2019 update). Diabetes Metab Res Rev. 2020;36 Suppl 1:e3280.
  4. Wounds UK (2021) Best Practice Statement: Addressing skin tone​ bias in wound care: assessing signs and symptoms in people with dark skin tones. Wounds UK, London.​ Available to download from: www.wounds-uk.com
  5. Magliano DJ et al. International Diabetes Federation Diabetes Atlas, 10th edition. Diabetes Atlas. 2021; accessed on November 4, 2022. Read more
  6. Best Practice Statement: Antimicrobial stewardship strategies for wound management. Wounds UK, London. 2020.