Removal of Staphylococcus aureus from skin using a combination antibiofilm approach

Yi Wang,Chuanwu Xi,Xiaojuan Tan,K Scott Phillips

doi:10.1038/s41522-018-0060-7

Abstract

Staphylococcus aureus (S. aureus) including methicillin resistant S. aureus (MRSA) is one of the primary microorganisms responsible for surgical site infection (SSI). Since S. aureus contamination is known to originate from the skin, eradicating it on the skin surface at surgical sites is an important intervention to reduce the chance of SSIs. Here we developed and evaluated the efficacy of a combination probiotic/brush sonication strategy for skin preparation at surgical, injection and insertion sites in medicine. A 24 h biofilm on porcine skin explants was used as a worst-case scenario for the evaluation of preparation strategies. Conventional ethanol wipes achieved 0.8~2 log reduction in viable bacteria depending on how many times wiped (x4 or x6). Brush sonication or probiotic supernatant pre-treatment alone achieved a similar reduction as ethanol wipes (1.4 and 0.7~1.4 log reduction, respectively). Notably, combining sonication and probiotic pre-treatment achieved a 4 log reduction in viable bacteria. In addition, probiotic supernatant incubation times as short as 2 h achieved the full effect of this reduction in the combined strategy. These findings suggest the promising potential of combination-format skin preparation strategies that can be developed to more effectively penetrate cracks and folds in the skin to remove biofilms.

Highlights

Surgical site infection (SSI) is the most common (160,000~300,000 per year) and most costly healthcare-associated infection[1] in the United States and ranges from superficial skin infection to lifethreatening postoperative complication
After normalizing the viable number of PC to 108 CFU cm−2, the PB2 + 2, PB2 + 24, and combined with brush sonication PB2 + 2 + B, PB2 + 24 + B bioburden levels resulted in surface bacterial densities of (24.6 ± 14) × 108, (2.97 ± 2.7) × 108, (0.00674 ± 0.0015) × 108, and (0.00742 ± 0.0055) × 108 CFU cm−2, respectively
Effect of alcohol wipe and brush sonication on skin S. aureus biofilm removal Porcine skin surface was inoculated with S. aureus (105 CFU mL−1) and cultured 24 h for biofilm formation

Summary

Introduction

Surgical site infection (SSI) is the most common (160,000~300,000 per year) and most costly healthcare-associated infection[1] in the United States and ranges from superficial skin infection to lifethreatening postoperative complication Foreign materials such as indwelling and implanted medical devices increase the risk of SSI significantly because less bioburden—as low as 100 CFU—is needed to cause infection.[2] According to the 1999 CDC Guideline for Prevention of SSI, the endogenous microbes of a patient’s skin and mucous membrane are the primary source of pathogen contamination for most SSIs.[3] Preventing initial bioburden transfer from the skin to foreign materials and adjacent tissue is thought to be an important intervention to prevent medical device associated SSI.[4,5] current research on preventing medical device associated infections has focused more on antimicrobial biomaterials and sterile practices (such as handwashing) than on understanding how bioburden is transferred from the skin surrounding a penetration site. This could improve antimicrobial stewardship by reducing the use of antibiotics and antimicrobials.[6]

Results

Discussion

Conclusion