Microbiological evaluation of resection margins of the infected diabetic foot ulcer.

AIM: To evaluate the impact of surgical debridement on the microbiology of resection margins of an infected diabetic foot ulcer and to compare the use of marginal sampling as a guide for antimicrobial therapy. METHODS: Forty consecutive participants were studied. Tissue samples from infected diabetic foot ulcers were obtained at first contact by podiatrists. After surgical debridement to macroscopically healthy tissue, multiple samples were obtained from the margins of the residuum and also from excised non-viable tissue. Debridement was done by a single surgeon. Bacterial species were classified according to pathogenic potential a priori into Red Group-Definite pathogen causing infection, Yellow Group-Likely to be causing infection if present in more than one specimen and Green Group -Commensals, not causing infection. RESULTS: There was a relative reduction of 49% (p = 0.002) in bacteria in the most pathogenic (red) group, and 59% (p = 0.002) in the yellow group in podiatry samples compared with resection specimen. Positive cultures from margins of the residuum were observed in 75% of cases. There was a relative reduction of 67% (p = 0.0001) in bacteria in the red and 48% (p = 0.06) in the yellow group in marginal samples from the residuum compared with podiatry samples. CONCLUSIONS: After surgical debridement to healthy tissue, positive cultures from marginal tissue samples provided vital information on the presence of pathogenic bacteria. This allowed antibiotics to be individualised post-surgical debridement.

Modern Orthopedic Inpatient Care of the Orthopedic Patient With Diabetic Foot Disease.

In this article, we describe emergency and elective pathways within our orthopedic multidisciplinary inpatient care of patients with diabetic foot problems. We performed a retrospective cohort review of 19 complex patients requiring orthopedic surgical treatment of infected ulceration or Charcot feet or deformity at our institution. A total of 30 admissions (19 emergency, 11 elective) were included. The pathways were coordinated by a multidisciplinary team and comprised initial assessment and investigation and a series of key events, which consisted of emergency and elective surgery together with the introduction, and change of intravenous antibiotics when indicated. Patients had rigorous microbiological assessment, in the form of deep ulcer swabs, operative tissue specimens, joint aspirates, and blood cultures according to their clinical presentation as well as close clinical and biochemical surveillance, which expedited the prompt institution of key events. Outcomes were assessed using amputation rates and patient satisfaction. In the emergency group, there were 5.6 ± 3.0 (mean ± SD) key events per admission, including 4.2 ± 2.1 antibiotic changes. In the elective group, there were 4.8 ± 1.4 key events per inpatient episode, with 3.7 ± 1.3 antibiotic changes. Overall, there were 3 minor amputations, and no major amputations. The podiatric and surgical tissue specimens showed a wide array of Gram-positive, Gram-negative, aerobic and anaerobic isolates and 15% of blood cultures showed bacteremia. When 9 podiatric specimens were compared with 9 contemporaneous surgical samples, there was concordance in 2 out of 9 pairs. We have described the successful modern care of the orthopedic diabetic foot patient, which involves close clinical, microbiological, and biochemical surveillance by the multidisciplinary team directing patients through emergency and elective pathways. This has enabled successful surgical intervention involving debridement, pressure relief, and stabilization, with low rates of amputation.