In vitro susceptibility of Propionibacterium acnes to simulated intrawound vancomycin concentrations

Abstract

BackgroundThere is convincing evidence supporting the prophylactic use of intrawound vancomycin powder in spinal fusion surgery and mounting evidence in the arthroplasty literature suggesting that it can reduce surgical site infections. As a result, a number of shoulder arthroplasty surgeons have adopted this practice, despite a paucity of evidence and the presence of a pathogen that is, for the most part, unique to this area of the body—Propionibacterium acnes. The purpose of this study was to evaluate the efficacy of vancomycin against planktonic P. acnes in vitro, using time-dependent concentrations one would expect in vivo after intra-articular application.MethodsIntrawound vancomycin concentrations were interpolated and extrapolated from existing in vivo data. Planktonic P. acnes was then subjected to a time-kill analysis during 96 hours. At each time point, the inoculum was centrifuged into pellet form and then reconstituted for serial drop counts onto blood agar plates. After anaerobic incubation, colony-forming units were counted, and log10 colony-forming units per milliliter were determined.ResultsEarly time points grew to confluence, and thus colony-forming units per milliliter were not calculated. However, at 12 hours of vancomycin treatment, distinct colonies were appreciated. Notably, there was a 3 × log10 reduction in colony-forming units per milliliter between 12 and 48 hours, denoting bactericidal activity. In addition, P. acnes was completely eradicated after 3 days of treatment.ConclusionWhen administered in a fashion meant to simulate time-dependent in vivo intrawound concentrations, vancomycin exhibited bactericidal activity against P. acnes. This may lend credence to the prophylactic use of vancomycin in shoulder surgery.

Is there value in the routine practice of discarding the incision scalpel from the surgical field to prevent deep wound contamination with Cutibacterium acnes?

“…3,7,20,25 In addition, perioperative intravenous antibiotics, including cefazolin, ceftriaxone, vancomycin, and doxycycline, as well as vancomycin powder (intraoperatively), are administered but have varying degrees of published success. 3,[8][9][10]18,19 Lee et al have indicated the inadequacy of chlorhexidine prep alone in eradicating dermal layers of C acnes. 11 Given the persistence of C acnes despite antibiotics and skin scrub, Hsu has suggested specific attention to implant handling (avoiding dermal contact) and maximizing other methods of maintaining sterility.…”

“…Standard skin prep solutions (eg, chlorhexidine gluconate, betadine soap) in addition to solutions specifically targeted to eradicate C acnes (eg, hydrogen peroxide, benzoyl peroxide, and intraoperative vancomycin powder) are commonly used; however, no consensus exists regarding a standardized protocol. 2,3,8,11,15,20,25 Despite these multifaceted approaches to prevention, periprosthetic infections with C acnes have persisted and remain a significant challenge. 21 The authors propose this study as a pilot work to identify the potential presence of culture-identifiable C acnes present on the scalpel blade used for initial skin incision despite exhaustive skin prep protocols to eradicate them.…”

Cutibacterium (Formerly Propionibacterium) acnes Keratitis: A Review

“…56 Several authors in the field consider vancomycin to be the most potent treatment against CAK. 13,25,27 The reasoning is that (1) C. acnes has consistently shown close to 100% susceptibility to vancomycin 57 and (2) vancomycin has a lower minimum bactericidal concentration against C. acnes compared with other antibiotics, [58][59][60] potentially reducing the amount of drug required to be delivered to the cornea. It is important to note, however, that just because vancomycin is considered the most potent antibiotic against CAK does not mean it is the most common for early treatment.…”

Outpatient Total Shoulder Replacement Procedures

“…This can help minimize the number of trays that need to be available during the procedure. and part over the deltopectoral closure [17][18][19][20][21]. A running absorbable stitch is used to close the skin along with skin glue.…”