Executive Summary: 2012 Infectious Diseases Society of America Clinical Practice Guideline for the Diagnosis and Treatment of Diabetic Foot Infectionsa

Abstract

Foot infections are a common and serious problem in persons with diabetes. Diabetic foot infections (DFIs) typically begin in a wound, most often a neuropathic ulceration. While all wounds are colonized with microorganisms, the presence of infection is defined by ≥2 classic findings of inflammation or purulence. Infections are then classified into mild (superficial and limited in size and depth), moderate (deeper or more extensive), or severe (accompanied by systemic signs or metabolic perturbations). This classification system, along with a vascular assessment, helps determine which patients should be hospitalized, which may require special imaging procedures or surgical interventions, and which will require amputation. Most DFIs are polymicrobial, with aerobic gram-positive cocci (GPC), and especially staphylococci, the most common causative organisms. Aerobic gram-negative bacilli are frequently copathogens in infections that are chronic or follow antibiotic treatment, and obligate anaerobes may be copathogens in ischemic or necrotic wounds. Wounds without evidence of soft tissue or bone infection do not require antibiotic therapy. For infected wounds, obtain a post-debridement specimen (preferably of tissue) for aerobic and anaerobic culture. Empiric antibiotic therapy can be narrowly targeted at GPC in many acutely infected patients, but those at risk for infection with antibiotic-resistant organisms or with chronic, previously treated, or severe infections usually require broader spectrum regimens. Imaging is helpful in most DFIs; plain radiographs may be sufficient, but magnetic resonance imaging is far more sensitive and specific. Osteomyelitis occurs in many diabetic patients with a foot wound and can be difficult to diagnose (optimally defined by bone culture and histology) and treat (often requiring surgical debridement or resection, and/or prolonged antibiotic therapy). Most DFIs require some surgical intervention, ranging from minor (debridement) to major (resection, amputation). Wounds must also be properly dressed and off-loaded of pressure, and patients need regular follow-up. An ischemic foot may require revascularization, and some nonresponding patients may benefit from selected adjunctive measures. Employing multidisciplinary foot teams improves outcomes. Clinicians and healthcare organizations should attempt to monitor, and thereby improve, their outcomes and processes in caring for DFIs.

Six-Week Versus Twelve-Week Antibiotic Therapy for Nonsurgically Treated Diabetic Foot Osteomyelitis: A Multicenter Open-Label Controlled Randomized Study

“…According to the recent Infectious Diseases Society of America guidelines, antibiotic therapy should be continued for 6 to 12 weeks if infected bone or soft tissues remain despite surgery (8). According to the same guidelines, antibiotics should be maintained for 12 weeks or more in patients for whom the resection of infected and necrotic bone could not be done for any reason (8). This prospective randomized study confirms the possibility of treating selected diabetic patients with osteomyelitis of the foot without surgery.…”

“…However, there is no evidence that antibiotic therapy for .6 weeks improves cure rates, as no randomized trials compared different durations of antibiotic treatment for DFO or for any other sort of chronic osteomyelitis (12). According to the recent Infectious Diseases Society of America guidelines, antibiotic therapy should be continued for 6 to 12 weeks if infected bone or soft tissues remain despite surgery (8). According to the same guidelines, antibiotics should be maintained for 12 weeks or more in patients for whom the resection of infected and necrotic bone could not be done for any reason (8).…”

“…A recent prospective randomized study conducted by Lázaro-Martínez et al (7) showed that antibiotics and surgical treatment have similar outcomes in patients with neuropathic forefoot ulcers complicated by osteomyelitis without ischemia or necrotizing soft tissue infections. According to the Infectious Diseases Society of America guidelines, surgical treatment of osteomyelitis is not necessary when 1) surgery would cause unacceptable loss of function, 2) there is an untreatable limb ischemia, 3) the infection is confined to the forefoot with minimal soft tissue loss, or 4) surgery is considered inappropriate or undesirable by the patient and health care professional (8). The medical approach to DFO is often criticized for collateral damage due to antibiotic use, especially the emergence of bacterial resistance, but also adverse events, in particular, Clostridium difficile-associated diarrhea (CDAD), along with significant cost (1).…”

“…However, the optimal duration of antibiotic treatment of osteomyelitis complicating foot wounds in non-surgically treated diabetic patients is currently unknown (1). International guidelines recommend $3 months of antibiotic therapy in the absence of surgery or in case of residual dead bone after surgery (8). Antibiotic use encourages antimicrobial resistance, incurs financial cost, and may cause drugrelated adverse effects.…”

Nano-Engineered Biomaterials for Tissue Regeneration: What Has Been Achieved So Far?

“…Statistics point to the fact that DFU and DFI are the major underlying causes for hospitalization and lower limb amputation (Uckay et al, 2015). The current guidelines for treating DFI include systematic antimicrobial therapy, which often does not work in moderate to severe cases (Lipsky et al, 2012;Uckay et al, 2015). This is combined with surgical procedures (Pinney et al, 2002;Mueller et al, 2003;Greenhagen et al, 2012;Colen et al, 2013;Cychosz et al, 2015), or revascularization, in combination with non-surgical wound care therapies, such as custom shoes and orthotics, which to this day remains unclear if they actually prevent the onset of DFU (Cychosz et al, 2015).…”