In vitro susceptibility of methicillin-resistant and methicillin-susceptible strains of Staphylococcus aureus to two different cold atmospheric plasma sources.

Background: Staphylococcus aureus may be the most important wound pathogen and causative for most of surgical site infections. As many anti-staphylococcal drugs are useless because of resistance, novel antimicrobial strategies are strongly needed and may be provided by cold atmospheric plasma (CP), which is being currently investigated for antiseptic efficacy. Methods: To test the antimicrobial properties of CP against Staphylococcus aureus, 168 methicillin-susceptible isolates (MSSA) and 50 methicillin-resistant isolates (MRSA) were treated with two technically different plasma sources [an atmospheric pressure plasma jet (APPJ) and a dielectric barrier discharge plasma (DBD)] in vitro. Results: CP treatment allowed a reproducible and significant growth reduction of MRSA and MSSA. However, MRSA was significantly less susceptible to treatment with DBD than was MSSA, while no difference between MRSA and MSSA was found using APPJ. Conclusions: As the initial physical antiseptic on skin, CP may be suitable for rapid decolonization of microbial pathogens in vivo. Each device must undergo validated efficacy testing prior to clinical application, as device related differences may occur. [ABSTRACT FROM AUTHOR]