Guideline sources The following summarized guidelines for the evaluation and management of diabetic foot infection (DFI) are prepared by our editorial team based on guidelines from the Infectious Diseases Society of America (IDSA/IWGDF 2023), the International Working Group on the Diabetic Foot (IWGDF/NHMRC 2022), the Society for Vascular Medicine (SVM/SVS/APMA 2016), and the Infectious Diseases Society of America (IDSA 2012). 1 2 3 4 5 5 5 6 Definition DFI is a micro-vascular complication characterized by soft tissue or bone infection below the malleoli in a diabetic. 5 Epidemiology DFI is caused by an amalgamation of neuropathy, vasculopathy, immunopathy, and foot ulcer infected with microbes (S. aureus, Proteus species, E. coli, Peptostreptococcus, Veilonella, and Bacteroides species). 5 Disease course https://web.pathway.md/diseases/recJSELILLPoWNtKg 1/10 6/29/23, 10:13 PM Diabetic foot infection Pathway Clinical manifestations include longstanding ulceration of a foot, constitutional symptoms (fever, tachycardia, tachypnea) of infection, wound erythema, hyperkeratosis, anhidrosis, fissures, blisters, nail disorders, and necrosis. Chronic infection may lead to osteomyelitis, gangrene, metabolic instability, and septic shock. 5 Prognosis and risk of recurrence The all-cause mortality associated with lower extremity amputation is 86.80 per 1,000 person- years. 6 Pathway Pathway Diabetic foot infection Diabetic foot infection Diagnosis and investigation Management Guidelines 1. Screening and diagnosis Diagnostic criteria: As per IWGDF 2023 guidelines, diagnose diabetes-related soft tissue infection clinically based on local or systemic signs and symptoms of inflammation. B As per IDSA 2012 guidelines, diagnose DFI in patients with at least 2 classic symptoms or signs of inflammation (erythema, warmth, tenderness, pain, or induration) or purulent secretions. B 2. Classification and risk stratification Severity assessment: As per IWGDF 2023 guidelines, use the IWGDF/IDSA classification scheme to assess the severity of any DFI. B As per IDSA 2012 guidelines, use a validated classification system, such as the IWGDF system, to classify DFIs, help define severity, and predict outcomes. A Show 2 more 3. Diagnostic investigations General principles: assess patients with diabetes presenting with a foot wound at 3 levels: the patient as a whole, the affected foot or limb, and the infected wound. B Physical examination: As per IWGDF 2023 guidelines: Avoid using foot temperature (however measured) for diagnosing DFI. D https://web.pathway.md/diseases/recJSELILLPoWNtKg 2/10 6/29/23, 10:13 PM Diabetic foot infection Pathway Consider obtaining the probe-to-bone test, in combination with plain X-rays and ESR (or CRP or procalcitonin), for the diagnosis of diabetic foot osteomyelitis. C As per SVS 2016 guidelines: Assess for infection on initial presentation of all patients with diabetic foot ulcers. B Consider obtaining the probe-to-bone test to aid in the diagnosis of diabetic foot osteomyelitis in patients with DFI with an open wound. C As per IDSA 2012 guidelines, assess for classic signs of inflammation (redness, warmth, swelling, tenderness, or pain) or purulent secretions, as well as additional or secondary signs (nonpurulent secretions, friable or discolored granulation tissue, undermining of wound edges, foul odor) for the evaluation of DFI. B Show 2 more Inflammatory markers: Obtain inflammatory serum biomarkers, such as CRP, ESR, or procalcitonin, in patients with diabetes and a possible infected foot ulcer if the clinical examination is diagnostically equivocal or uninterpretable. E Consider obtaining ESR, CRP, or procalcitonin, in combination with probe-to-bone testing and plain X-rays, for the diagnosis of diabetic foot osteomyelitis. C Radiography: As per IWGDF 2023 guidelines, consider obtaining plain X-rays for the diagnosis of diabetic foot osteomyelitis. C As per SVS 2016 guidelines, consider obtaining serial plain radiographs of the affected foot to identify bone abnormalities (deformity, destruction), soft tissue gas, and radiopaque foreign bodies in all patients presenting with a new DFI. C As per IDSA 2012 guidelines: Obtain plain radiographs of the affected foot to assess for bony abnormalities (deformity, destruction) and soft tissue gas and radio-opaque foreign bodies. B Consider obtaining serial plain radiographs to diagnose or monitor suspected diabetic foot osteomyelitis. C Magnetic resonance imaging: As per IWGDF 2023 guidelines, obtain MRI when the diagnosis of diabetic foot osteomyelitis remains in doubt despite clinical assessment, radiography, and laboratory tests. B As per SVS 2016 guidelines, obtain MRI in patients requiring additional (more sensitive or specific) imaging, particularly if a soft tissue abscess is suspected or the diagnosis of osteomyelitis remains uncertain. Obtain MRI for the diagnosis of osteomyelitis if the probe-to- bone test is inconclusive or the plain radiography is not useful. B As per IDSA 2012 guidelines: Obtain an MRI of the lower extremities in patients requiring further imaging, particularly when a soft tissue abscess is suspected or the diagnosis of osteomyelitis remains uncertain. B Suspect osteomyelitis as a potential complication of any infected, deep, or large foot ulcer, especially if chronic or overlies a bony prominence. B Tagged WBC and bone scans: https://web.pathway.md/diseases/recJSELILLPoWNtKg 3/10 6/29/23, 10:13 PM Diabetic foot infection Pathway As per IWGDF 2023 guidelines, consider obtaining WBC scintigraphy as an alternative to MRI for the diagnosis of diabetic foot osteomyelitis. C As per SVS 2016 guidelines, consider obtaining WBC or anti-granulocyte scintigraphy, preferably combined with a bone scan, in patients with suspected diabetic foot osteomyelitis if MRI is contraindicated or unavailable. C As per IDSA 2012 guidelines: Consider obtaining labeled WBC scintigraphy combined with a radionuclide bone scan for the diagnosis of diabetic foot osteomyelitis if MRI is unavailable or contraindicated. C Consider obtaining WBC or anti-granulocyte scintigraphy, preferably combined with a bone scan, to evaluate for diabetic foot osteomyelitis if MRI is unavailable or contraindicated. C Other imaging modalities: as per IWGDF 2023 guidelines, consider obtaining positron emission tomography or single photon emission CT as an alternative to MRI for the diagnosis of diabetic foot osteomyelitis. C Wound culture: As per IWGDF 2023 guidelines, consider obtaining microbiological culture, preferably by aseptically collecting a tissue specimen (curettage or biopsy) from the wound, to determine the causative microorganisms in patients with suspected soft tissue DFI. C Show 2 more As per IDSA 2012 guidelines, do not collect specimens for culture for clinically uninfected wounds. D Show 3 more 4. Diagnostic procedures Bone culture and histology: As per IWGDF 2023 guidelines, consider obtaining bone (rather than soft tissue) samples for culture, either intraoperatively or percutaneously, in patients with suspected diabetic foot osteomyelitis (before or after treatment). C As per SVS 2016 guidelines: Obtain bone culture and histology to confirm the diagnosis in patients at high risk for diabetic foot osteomyelitis. Send the samples for culture and histology if the bone is debrided to treat osteomyelitis. B Consider performing a bone biopsy in patients not undergoing bone debridement if faced with diagnostic uncertainty, inadequate culture information, or failure of response to empirical treatment. C 5. Medical management General principles: consider offering either primarily surgical or primarily medical strategies for the treatment of diabetic foot osteomyelitis in properly selected patients. C Setting of care: https://web.pathway.md/diseases/recJSELILLPoWNtKg 4/10 6/29/23, 10:13 PM Diabetic foot infection Pathway As per IDSA 2023 guidelines, consider hospitalizing patients with severe DFI or moderate infection associated with key relevant morbidities. C As per IDSA 2012 guidelines: Hospitalize patients with severe infection, patients with moderate infection and complicating features (such as severe peripheral arterial disease or lack of home support), and patients unable to comply with outpatient treatment for psychological or social reasons. B Consider hospitalizing patients not meeting the above criteria but not improving with outpatient therapy. B Empiric antibiotic therapy, diabetic foot infection: As per IDSA/IWGDF 2023 guidelines, do not initiate systemic antibiotic therapy in patients with uninfected foot ulcers when the goal is to reduce the risk of new infection or to promote ulcer healing. D Show 4 more As per IDSA 2012 guidelines, do not initiate antibiotic therapy in patients with clinically uninfected wounds. D Show 7 more Empiric antibiotic therapy (diabetic foot osteomyelitis): consider initiating antibiotic therapy without surgery in case of forefoot osteomyelitis without an immediate need for incision and drainage to control infection, without PAD, and without exposed bone. C Definitive antibiotic therapy: tailor definitive therapy according to the results of an appropriately obtained culture and sensitivity testing of a wound specimen, as well as the patient's clinical response to the empiric regimen. B Show 2 more Updated evidence: OVIVA In patients being treated for bone or joint infection, oral antibiotic therapy was noninferior to IV antibiotic therapy with respect to definitive treatment failure at 1 year. Li HK et al. N Engl J Med. 2019 Jan 31. Duration of treatment, diabetic foot infection: As per IDSA/IWGDF 2023 guidelines, continue antibiotic therapy for 1-2 weeks in patients with skin or soft tissue DFI. A Show 2 more As per IDSA 2012 guidelines: Consider completing 1-2 weeks of antibiotic therapy for mild infections and 2-3 weeks of antibiotic therapy for moderate-to-severe infections. C Consider continuing antibiotic therapy until, but not beyond, resolution of findings of infection, but not through complete healing of the wound. C Duration of treatment, diabetic foot osteomyelitis: As per IDSA/IWGDF 2023 guidelines: https://web.pathway.md/diseases/recJSELILLPoWNtKg 5/10 6/29/23, 10:13 PM Diabetic foot infection Pathway Consider continuing antibiotic therapy for up to 3 weeks after minor amputation for diabetic foot osteomyelitis and positive bone margin culture and 6 weeks for diabetic foot osteomyelitis without bone resection or amputation. C Use the outcome at a minimum follow-up duration of 6 months after the end of the antibiotic therapy to diagnose remission of diabetic foot osteomyelitis. E As per NHMRC/IWGDF 2022 guidelines, continue antibiotic therapy for no longer than 6 weeks in patients with diabetic foot osteomyelitis. Reconsider the need for collecting a bone specimen for culture, undertaking surgical resection, or selecting an alternative antibiotic regimen if the infection does not clinically improve within the first 2-4 weeks. B Show 3 more As per IDSA 2012 guidelines: Consider continuing antibiotic therapy for 2-5 days in patients with diabetic foot osteomyelitis undergone a radical resection leaving no remaining infected tissue. C Consider continuing treatment for 4 weeks in the presence of persistent infected or necrotic bone. C Topical antimicrobials: As per IDSA 2023 guidelines: Do not use local antibiotics in patients with uninfected foot ulcers when the goal is to reduce the risk of new infection or to promote ulcer healing. D Avoid using topical (sponge, cream, and cement) antibiotics in combination with systemic antibiotics for the treatment of diabetic soft-tissue infection or foot osteomyelitis. D As per IWGDF 2022 guidelines, avoid using any currently available topical antimicrobial agents for the treatment of patients with mild DFIs. D Glycemic control: consider ensuring adequate glycemic control (HbA1c < 7% with strategies to minimize hypoglycemia) to reduce the incidence of diabetic foot ulcers and infections, with subsequent risk of amputation. C 6. Therapeutic procedures Adjunctive therapies, diabetic foot infection: As per IDSA/IWGDF 2023 guidelines: Avoid offering the following adjunctive therapies for the management of DFIs: G-CSFs topical antiseptics or silver preparations honey bacteriophage therapy negative pressure wound therapy (with or without instillation). D Avoid offering hyperbaric oxygen therapy or topical oxygen therapy as an adjunctive treatment for the sole indication of treating a DFI. D As per IDSA 2012 guidelines, consider offering the following adjunctive therapies for selected slow-healing diabetic foot wounds: bioengineered skin equivalents C https://web.pathway.md/diseases/recJSELILLPoWNtKg 6/10 6/29/23, 10:13 PM Diabetic foot infection Pathway growth factors, G-CSFs C hyperbaric oxygen therapy B negative pressure wound therapy. C Adjunctive therapies (diabetic foot osteomyelitis): Avoid offering the following adjunctive therapies for the treatment of diabetic foot osteomyelitis: hyperbaric oxygen therapy growth factors, including G-CSF maggots (larvae) negative pressure therapy (such as vacuum-assisted closure). D 7. Surgical interventions Wound care: provide appropriate wound care in patients with diabetic foot ulcers. B Show 4 more Indications for surgeon consultation: As per IWGDF 2023 guidelines: Obtain urgent surgical consultation in patients with severe DFI or moderate foot infection complicated by extensive gangrene, necrotizing infection, signs suggesting deep (below the fascia) abscess, compartment syndrome, or severe lower limb ischemia. E Obtain an urgent consultation with a surgical specialist and a vascular specialist to determine the indications and timings of a drainage procedure and/or revascularization procedure in patients with diabetes, PAD, and a foot ulcer or gangrene with an infection involving any portion of the foot. E As per IWGDF 2022 guidelines, obtain urgent surgical consultation for patients with osteomyelitis with severe infection or moderate infection complicated by extensive gangrene, necrotizing infection, signs suggesting deep (below the fascia) abscess or compartment syndrome, or severe lower limb ischemia. B As per IDSA 2012 guidelines: Consider requesting an assessment by a surgeon for patients with a moderate or severe DFI. C Consult with a vascular surgeon to evaluate for revascularization whenever ischemia complicates a DFI, especially in patients with a critically ischemic limb. B Wound debridement: As per SVS 2016 guidelines, perform initial sharp debridement of all infected diabetic ulcers and urgent surgical intervention for foot infections involving abscess, gas, or necrotizing fasciitis. B As per IDSA 2012 guidelines, perform debridement of wounds with necrotic tissue or surrounding callus. B Surgical interventions: As per IDSA 2023 guidelines: Consider performing early (within 24-48 hours) surgery combined with antibiotics to remove infected and necrotic tissue in patients with moderate-to-severe DFIs. C https://web.pathway.md/diseases/recJSELILLPoWNtKg 7/10 6/29/23, 10:13 PM Diabetic foot infection Pathway Consider performing surgical resection of infected bone combined with systemic antibiotics in patients with diabetic foot osteomyelitis. C As per IWGDF 2022 guidelines, obtain urgent evaluation for surgery and intensive postoperative medical and surgical follow-up in patients with probable diabetic foot osteomyelitis with concomitant soft tissue infection. B As per IDSA 2012 guidelines, perform urgent surgical intervention for foot infections accompanied by gas in the deeper tissues, an abscess, or necrotizing fasciitis, and less urgent surgery for wounds with substantial nonviable tissue or extensive bone or joint involvement. B 8. Follow-up and surveillance Discharge criteria: Discharge patients with DFI meeting the following criteria: patient is clinically stable, and acceptable glycemic control has been attained patient has undergone any urgently needed surgery patient is able to manage on his/her own or with help at the designated discharge location patient has a well-defined plan that includes an appropriate antibiotic regimen to which he/she will adhere, an off-loading scheme if needed, specific wound care instructions, and appropriate outpatient follow-up. B Clinical findings Symptoms Past medical history Ankle swelling Bacterial infection Changes in foot skin color and temperature Fungal infection of the foot Inflammation Leg pain Peripheral vascular disease Leg swelling Poorly controlled diabetes Wounds or sores Integument exam Neurological exam Ingrowing nail Peripheral neuropathy Skin ulceration Wound infection Lab findings Hyperglycemia Likelihood Ratios Pertinent positives The following findings increase the probability of lower extremity osteomyelitis in adult patients with diabetes. 6 Finding LR+ Value https://web.pathway.md/diseases/recJSELILLPoWNtKg 8/10 6/29/23, 10:13 PM Diabetic foot infection Pathway Increased ESR 11 (1.6-79) Increased ulcer size (> 2 cm ) 7.2 (1.1-49) Positive probe-to-bone test 6.4 (3.6-11) Presence of clinical impression of osteomyelitis 5.5 (1.8-17) bone destruction alone or in combination with soft tissue swelling; localized osteopenia or periosteal reaction in the absence of fracture or neuropathic joint disease Show 2 more Pertinent negatives The following findings decrease the probability of lower extremity osteomyelitis in adult patients with diabetes. 6 Finding LR- Value Absence of findings of osteomyelitis 0.14 (0.08-0.26) Negative probe-to-bone test 0.39 (0.20-0.76) ulcer size not increased ( 2 cm ) 0.48 (0.31-0.76) Absence of clinical impression of osteomyelitis 0.54 (0.30-0.97) bone destruction alone or in combination with soft tissue swelling; localized osteopenia or periosteal reaction in the absence of fracture or neuropathic joint disease Show 1 more References 1. Lipsky BA, Berendt AR, Cornia PB et al. 2012 Infectious Diseases Society of America clinical practice guideline for the diagnosis and treatment of diabetic foot infections. Clin Infect Dis. 2012 Jun;54 12):e132 73. Open 2. ric Senneville, Zaina Albalawi, Suzanne A. van Asten et al. Guidelines on the diagnosis and treatment of foot infection in persons with diabetes. IWGDF Guidelines. 2023. Open 3. Robert J Commons, James Charles, Jane Cheney et al. Australian guideline on management of diabetes-related foot infection: part of the 2021 Australian evidence-based guidelines for diabetes- related foot disease. J Foot Ankle Res. 2022 Jun 9;15 1 47. Open 4. Anil Hingorani, Glenn M LaMuraglia, Peter Henke et al. The management of diabetic foot: A clinical practice guideline by the Society for Vascular Surgery in collaboration with the American Podiatric Medical Association and the Society for Vascular Medicine. J Vasc Surg. 2016 Feb;63 2 Suppl):3S 21S. Open 5. Saba Noor, Rizwan Ullah Khan, Jamal Ahmad. Understanding Diabetic Foot Infection and its Management. Diabetes Metab Syndr. Apr-Jun 2017;11 2 149 156. Open 6. Khalid Al-Rubeaan, Mohammad K Almashouq, Amira M Youssef et al. All-cause mortality among diabetic foot patients and related risk factors in Saudi Arabia. 2017 Nov 27;12 11):e0188097.2017 Nov 27;12 11):e0188097. Open 7. Milne WK, Carpenter CR. Evidence-based emergency medicine/rational clinical examination abstract. Does this patient with diabetes have osteomyelitis of the lower extremity?. Ann Emerg Med. 2009 May;53 5 677 9. Open https://web.pathway.md/diseases/recJSELILLPoWNtKg 9/10 6/29/23, 10:13 PM Diabetic foot infection Pathway 8. Sonia Butalia, MD, Valerie A. Palda et al. Does This Patient With Diabetes Have Osteomyelitis of the Lower Extremity?. JAMA. 2008;299 7 806 813. Open 9. Khalid Al-Rubeaan, Mohammad K. Almashouq, Amira M. Youssef et al. All-cause mortality among diabetic foot patients and related risk factors in Saudi Arabia. PLoS One. 2017; 12 11 e0188097. Open 10. American Diabetes Association Professional Practice Committee, American Diabetes Association Professional Practice Committee:, Draznin B et al. Standards of Medical Care in Diabetes-2022. Diabetes Care. 2022 Jan 1;45 Supplement_1 S1 S264. Open 11. Steven E. Kahn, Cheryl A.M. Anderson, John B. Buse et al. Standards of Care in Diabetes 2023. Diabetes Care. 2023 Jan;46 Supplement_1 S1 S291. Open https://web.pathway.md/diseases/recJSELILLPoWNtKg 10/10