Diabetic Foot Infections: Microbiology Made Modern?

Abstract

Many aspects of managing foot infections in patients with diabetes have improved dramatically and are summarized in recently published guidelines (1–3). Yet, the basic methods of determining the causative microorganisms from these infections by culturing wound specimens have remained largely unchanged for over a century. Obtaining a proper wound culture specimen allows the clinician to define the pathogens involved and their antibiotic susceptibility. Unfortunately, results of cultures are generally not available for at least 2–3 days. Thus, most antibiotic therapy for infections is selected empirically (4). By the time culture results arrive, they are usually too late to influence the initial antibiotic choice. Many clinicians, therefore, feel compelled to select an antibiotic regimen that will cover most of the likely bacteria for all but the mildest infections, leading to an unnecessarily broad spectrum of therapy. This overprescribing increases the likelihood of adverse drug effects, drives antibiotic resistance, and increases the cost of treatment. To the contrary, some clinicians conclude that it is not worthwhile to obtain cultures, believing that the belated results are unhelpful. This approach, however, makes it difficult to properly select an alternative regimen if the patient is failing to respond to the initial agent(s). The increasing incidence of antibiotic-resistant pathogens as causes of diabetic foot infections makes selecting empiric antibiotic therapy more difficult. Those who treat these patients are well aware of the growing problem of methicillin-resistant Staphylococcus aureus (MRSA), which is now frequently acquired in the community and in various types …