Epidemiology of Diabetic Foot Infection in the Metro-Detroit Area With a Focus on Independent Predictors for Pathogens Resistant to Recommended Empiric Antimicrobial Therapy

Abstract

BackgroundThe polymicrobial nature of diabetic foot infection (DFI) and the emergence of antimicrobial resistance have complicated DFI treatment. Current treatment guidelines for deep DFI recommend coverage of methicillin-resistant Staphylococcus aureus (MRSA) and susceptible Enterobacteriaceae. This study aimed to describe the epidemiology of DFI and to identify predictors for DFI associated with multidrug-resistant organisms (MDROs) and pathogens resistant to recommended treatment (PRRT).MethodsAdult patients admitted to Detroit Medical Center from January 2012 to December 2015 with DFI and positive cultures were included. Demographics, comorbidities, microbiological history, sepsis severity, and antimicrobial use within 3 months before DFI were obtained retrospectively. DFI-PRRT was defined as a DFI associated with a pathogen resistant to both vancomycin and ceftriaxone. DFI-MDRO pathogens included MRSA in addition to PRRT.ResultsSix-hundred forty-eight unique patients were included, with a mean age of 58.4 ± 13.7 years. DFI-MDRO accounted for 364 (56%) of the cohort, and 194 (30%) patients had DFI-PRRT. Independent predictors for DFI-PRRT included history of PRRT in a diabetic foot ulcer, antimicrobial exposure in the prior 90 days, peripheral vascular disease, and chronic kidney disease. Long-term care facility residence was independently associated with DFI due to ceftriaxone-resistant Enterobacteriaceae, and recent hospitalization was an independent predictor of DFI due to vancomycin-resistant Enterococcus.ConclusionsAn unexpectedly high prevalence of DFI-PRRT pathogens was identified. History of the same pathogen in a prior diabetic foot ulcer and recent antimicrobial exposure were independent predictors of DFI-PRRT and should be considered when selecting empiric DFI therapy.

Multidrug resistant organism predicts ulcer recurrence following surgical management of diabetic foot osteomyelitis

“…The overall rate of MDROs in DFO patients was 13.9%, which is comparable to some centres and less than others. 3 Consistent with published data, MRSA was the most common MDRO. 23 Patients with MDRO-DFO were more likely to have a negative outcome, including recurrent DFU, re-amputation, or death by 1 year.…”

“…The overall rate of MDROs in DFO patients was 13.9%, which is comparable to some centres and less than others 3 . Consistent with published data, MRSA was the most common MDRO 23 .…”

“…For this study, the following were defined as MDRO: methicillin‐resistant Staphylococcus aureus (MRSA), vancomycin‐resistant Enterococci (VRE), Enterobacteriaceae resistant to third‐generation cephalosporins and/or carbapenems ( Enterobacteriacae ‐R), Acinetobacter baumannii , and all susceptibility phenotypes of Pseudomonas aeruginosa , a definition used by previous studies 3 …”

“…Multidrug‐resistant organisms (MDROs) are often present in DFU: about one‐third of patients with a history of the previous hospitalisation for the same wound and 25% of patients with osteomyelitis had MDRO‐positive specimens 2 . Recent evidence suggests this is a growing concern in urban areas where the reported rate of MDROs in DFU reaches 56%, and approximately 30% of cultures are resistant to recommended treatment 3 . Evidence suggests that MDROs in DFU lead to worse clinical outcomes, including poor ulcer healing, increased treatment failure, increased readmission rates, and increased mortality 2,4‐7 …”

Dakin's solution in the treatment of severe diabetic foot infections

“…Its main interest relies on its potent debridement and its antiseptic proprieties, making it an attractive option to address heavily contaminated wounds with a large burden of necrotic tissue, in which the debris acts as privileged reservoirs for a high load of infective pathogens. DS has also shown superiority to other topical antiseptics in neutralising multidrug‐resistant bacteria, which are increasingly found in DF wounds and probably contribute to worse outcomes. Indeed, co‐infections are fairly frequent in our presented DF population, and a significant number is known for their antibiotic resistances, such as Pseudomonas aeruginosa , ESBL‐producing E .…”