Sonication of Kirschner Wire as a Tool for the Microbiological Diagnosis of Diabetic Foot Infection – Preliminary Results

Background: Diabetic foot infection (DFI) is the commonest diabetic problem requiring hospital admission. Culture yield can be challenging, particularly in the presence of biofilms. Literature confirms biofilms are ubiquitous in diabetic foot ulcer, although, there is not a microbiologic diagnostic approach regarding biofilm disruption on DFI. We postulated sonicating a stainless-steel wire along with tissue samples into the thioglycollate broth media (TBM) may improve the diagnosis of DFI. Method: Pro-spective unicentric study that assessed patients with DFI who underwent surgical debridement. The vascular surgery team collected tissue fragments and inoculated the specimens into three TBM to execute the conventional culture method (CCM), and ad-ditional fragments to place into other TBM along with a Kirschner wire (K-wire – Kw method). The microbiologist processed the samples and the resultant sonication fluid in aerobic sheep-blood agar after 24 hours, 5 and 10 days of incubation. Both methods were compared (Wilcoxon test; p < 0.05). Results: The number of pathogens isolated in each method was not statistically significant (p = 0.414): CM = 1.67 (± 0.92); KwM = 1.75 (± 0.94). The KwM was not inferior to CCM. In addition, despite the absence of statistical significance, the KwM detected more pathogens than CCM.