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Background: Most chronic wounds contain biofilm, and debridement remains the centerpiece of treatment. Enzymatic debridement is an effective tool in removing nonviable tissue, however, there is little evidence supporting its effect on planktonic and biofilm bacteria., Objective: This study evaluated the effects of a novel BBD agent on removal of nonviable tissue, biofilm, and microbial loads in patients with chronic ulcers., Materials and Methods: Twelve patients with DFU or VLU were treated with up to 8 once-daily applications of BBD and then followed for an additional 2 weeks. Punch biopsy specimens were collected and analyzed for biofilm, and fluorescence imaging was used to measure bacterial load., Results: Ten patients completed treatment, and 7 achieved complete debridement within a median of 2 applications (range, 2-8). By the end of the 2-week follow-up period, the mean ± SD reduction in wound area was 35% ± 38. In all 6 patients who were positive for biofilm at baseline, the biofilm was reduced to single individual or no detected microorganisms by the end of treatment. Red fluorescence for Staphylococcus aureus decreased from a mean of 1.09 cm² ± 0.58 before treatment to 0.39 cm² ± 0.25 after treatment. BBD was safe and well tolerated., Conclusion: Preliminary data suggest that BBD is safe and that it can be used to effectively debride DFU and VLU, reduce biofilm and planktonic bacterial load, and promote reduction in wound size.

Objective: Although needleless connectors (NCs) are widely used in clinical practice, they carry significant risk of bloodstream infection (BSI). In this study, we quantified differences in bacterial transfer and biofilm formation between various NCs., Design: Prospective, clinically simulated in vitro experimental study., Methods: We tested 20 NCs in a 5-day clinical simulation of Staphylococcus aureus inoculations onto NC septum surfaces, which were then flushed with saline and cultured for bacterial transfer. Biofilm formation was measured through destructive sampling of the connector-catheter system. Moreover, 8 NC design factors were evaluated for their influence on bacterial transfer and biofilm formation. This study was designed without a disinfection protocol to ascertain the intrinsic risk of each NC., Results: Clave Neutron and MicroClave had the lowest overall mean log density of bacteria in the flush compared to other NCs ( P < .05), except there were no statistically significant differences between Clave Neutron, Microclave, SafeTouch, and SafeAccess ( P ≥ .05). The amount of biofilm in the NC was positively associated with bacteria in the flush ( P < .0005). Among 8 design factors, flow path was most important, with the internal cannula associated with a statistically significant 1 log reduction (LR) in bacteria in the flush ( R 2 = 49%) and 0.5-2 LR in the connector ( R 2 = 34%). All factors together best explained bacteria in the flush ( R 2 = 65%) and biofilm in the connector ( R 2 = 48%)., Conclusions: Bacterial transfer and biofilm formation in the connector-catheter system varied statistically significantly between the 20 NCs, suggesting that NC choice can lower the risk of developing catheter-related BSIs.

One of the major causes of prosthetic joint failure is infection. Recently, coagulase negative Staphylococcus epidermidis has been identified as an emergent, nosocomial pathogen involved in subclinical prosthetic joint infections (PJIs). The diagnosis of PJIs mediated by S. epidermidis is usually complex and difficult due to the absence of acute clinical signs derived from the host immune system response. Therefore, analysis of protein patterns in biofilm-producing S. epidermidis allows for the examination of the molecular basis of biofilm formation. Thus, in the present study, the proteome of a clinical isolate S. epidermidis was analyzed when cultured in its planktonic or sessile form to examine protein expression changes depending on culture conditions. After 24 h of culture, sessile bacteria exhibited increased gene expression for ribosomal activity and for production of proteins related to the initial attachment phase, involved in the capsular polysaccharide/adhesin, surface associated proteins and peptidoglycan biosynthesis. Likewise, planktonic S. epidermidis was able to aggregate after 24 h, synthesizing the accumulation associate protein and cell-wall molecules through the activation of the YycFG and ArlRS, two component regulatory pathways. Prolonged culture under vigorous agitation generated a stressful growing environment triggering aggregation in a biofilm-like matrix as a mechanism to survive harsh conditions. Further studies will be essential to support these findings in order to further delineate the complex mechanisms of biofilm formation of S. epidermidis and they could provide the groundwork for the development of new drugs against biofilm-related infections, as well as the identification of novel biomarkers of subclinical or chronic infections mediated by these emerging, low virulence pathogens., (Copyright © 2020 Bottagisio, Barbacini, Bidossi, Torretta, deLancey-Pulcini, Gelfi, James, Lovati and Capitanio.)