What is the treatment (Ttt) of diabetic foot infection?

From the Guidelines

The treatment of diabetic foot infections should prioritize a comprehensive approach, including wound care, appropriate antibiotic therapy, and surgical intervention as needed, with a focus on individualized care based on the severity of the infection and the patient's overall health status. The management of diabetic foot infections involves several key components, including:

• Wound care with debridement of necrotic tissue and pressure offloading
• Appropriate antibiotic therapy, with the selection of antibiotics guided by the severity of the infection and the presence of any underlying conditions, such as peripheral artery disease (PAD) 1
• Surgical intervention, including drainage of abscesses, removal of infected bone, and revascularization procedures when needed
• Blood glucose control, targeting levels below 180 mg/dL to promote healing and reduce infection risk
• Regular wound assessment and proper dressing changes
• Multidisciplinary care involving endocrinology, infectious disease, vascular surgery, and podiatry specialists to optimize outcomes.

For mild infections, oral antibiotics such as amoxicillin-clavulanate (875/125 mg twice daily), cephalexin (500 mg four times daily), or clindamycin (300-450 mg four times daily) for 1-2 weeks are typically effective 1. Moderate to severe infections require broader coverage, often with initial intravenous therapy such as piperacillin-tazobactam (4.5g every 6-8 hours), ertapenem (1g daily), or vancomycin (15-20 mg/kg every 12 hours) plus either ceftazidime (2g every 8 hours) or cefepime (2g every 12 hours) for MRSA coverage. The duration of antibiotic therapy should be individualized, but typically ranges from 1-2 weeks for mild infections to 2-4 weeks for more severe cases, with adjustments based on culture results 1.

It is essential to note that the diagnosis of osteomyelitis can be challenging, and the use of conventional microbiology techniques, such as bone culture and histology, is recommended for the identification of pathogens 1. Imaging studies, including plain radiographs, magnetic resonance imaging (MRI), and positron emission tomography (PET), can also be helpful in diagnosing osteomyelitis and guiding treatment.

Overall, the treatment of diabetic foot infections requires a comprehensive and individualized approach, taking into account the severity of the infection, the presence of any underlying conditions, and the patient's overall health status, with the goal of promoting healing, reducing the risk of complications, and improving quality of life 1.

From the FDA Drug Label

1. 3 Skin and Skin Structure Infections Piperacillin and Tazobactam for Injection is indicated in adults for the treatment of uncomplicated and complicated skin and skin structure infections, including cellulitis, cutaneous abscesses and ischemic/diabetic foot infections caused by beta-lactamase producing isolates of Staphylococcus aureus. The treatment of diabetic foot infection with piperacillin-tazobactam (IV) is indicated for adults.

• The usual total daily dosage is 3.375 grams every six hours, totaling 13.5 grams.
• The usual duration of treatment is from 7 to 10 days 2.

From the Research

Diagnosis and Treatment of Diabetic Foot Infections

• Diabetic foot infections require attention to local and systemic issues and coordinated management, preferably by a multidisciplinary foot-care team 3
• The major predisposing factor to these infections is foot ulceration, which is usually related to peripheral neuropathy 3
• Aerobic Gram-positive cocci, particularly Staphylococcus aureus, are the predominant pathogens in diabetic foot infections 3, 4, 5

Empirical Antibiotic Therapy

• Empirical antibiotic therapy should be selected based on the severity of the infection and the likely etiologic agent(s) 3, 4
• Therapy aimed solely at aerobic Gram-positive cocci may be sufficient for mild-to-moderate infections in patients who have not recently received antibiotic therapy 3
• Broad-spectrum empirical therapy is not routinely required but is indicated for severe infections, pending culture results and antibiotic susceptibility data 3, 4

Duration of Antibiotic Therapy

• The duration of antibiotic therapy ranges from 1-2 weeks for mild soft tissue infections to over 6 weeks for osteomyelitis 3, 5
• Suggestions for the duration of antibiotic therapy are as follows: for mild infections, 1-2 weeks usually suffices, but some require an additional 1-2 weeks; for moderate and severe infections, usually 2-4 weeks is sufficient, depending on the structures involved, the adequacy of debridement, the type of soft-tissue wound cover, and wound vascularity 3

Role of Surgery

• Surgical consultation and intervention are necessary for infections accompanied by a deep abscess, extensive bone or joint involvement, crepitus, substantial necrosis or gangrene, or necrotizing fasciitis 3
• Evaluating the limb's arterial supply and revascularizing when indicated are particularly important 3

Adjunctive Therapies

• Granulocyte colony-stimulating factors and systemic hyperbaric oxygen therapy may help prevent amputations in patients with diabetic foot infections 3
• These treatments may be useful for severe infections or for those that have not adequately responded to therapy, despite correcting for all amenable local and systemic adverse factors 3