title: Propionibacterium persists in the skin despite standard surgical preparation.
abstract: BACKGROUND
  Propionibacterium acnes, which normally resides in the skin, is known to play a role in surgical site infection in orthopaedic surgery. Studies have suggested a persistence of propionibacteria on the skin surface, with rates of positive cultures ranging from 7% to 29% after surgical preparation. However, as Propionibacterium organisms normally reside in the dermal layer, these studies may underestimate the true prevalence of propionibacteria after surgical skin preparation. We hypothesized that, after surgical skin preparation, viable Propionibacterium remains in the dermis at a much higher rate than previously reported.
  
  
  METHODS
  Ten healthy male volunteers underwent skin preparation of the upper back with ChloraPrep (2% chlorhexidine gluconate and 70% isopropyl alcohol). Two 3-mm dermal punch biopsy specimens were obtained through the prepared skin and specifically cultured for P. acnes.
  
  
  RESULTS
  Seven volunteers had positive findings for Propionibacterium on dermal cultures after ChloraPrep skin preparation. The average time to positive cultures was 6.78 days.
  
  
  CONCLUSIONS
  This study found that Propionibacterium persists in the dermal tissue even after surface skin preparation with ChloraPrep. The 70% rate of persistence of propionibacteria after skin preparation is substantially higher than previously reported.
  
  
  CONCLUSIONS
  Propionibacteria are increasingly discussed as having an association with infection, implant failure, and degenerative disease. This study confirms the possibility that the dermal layer of skin may be the source of the bacteria.
authors.affiliation: Departments of Sports Medicine and Orthopaedic Surgery (M.J.L., S.M.R., and F.A.M.) and Microbiology (R.E.B.), Divisions of Allergy and Infectious Diseases (P.S.P.) and Laboratory Medicine and Clinical Microbiology (S.B-W.), University of Washington Medical Center, University of Washington, Box 356500, 1959 N.E. Pacific Street, Seattle, WA 98195. E-mail address for M.J. Lee: jihoon2000@hotmail.com.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lee
authors.affiliation: Departments of Sports Medicine and Orthopaedic Surgery (M.J.L., S.M.R., and F.A.M.) and Microbiology (R.E.B.), Divisions of Allergy and Infectious Diseases (P.S.P.) and Laboratory Medicine and Clinical Microbiology (S.B-W.), University of Washington Medical Center, University of Washington, Box 356500, 1959 N.E. Pacific Street, Seattle, WA 98195. E-mail address for M.J. Lee: jihoon2000@hotmail.com.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Pottinger
authors.affiliation: Departments of Sports Medicine and Orthopaedic Surgery (M.J.L., S.M.R., and F.A.M.) and Microbiology (R.E.B.), Divisions of Allergy and Infectious Diseases (P.S.P.) and Laboratory Medicine and Clinical Microbiology (S.B-W.), University of Washington Medical Center, University of Washington, Box 356500, 1959 N.E. Pacific Street, Seattle, WA 98195. E-mail address for M.J. Lee: jihoon2000@hotmail.com.
authors.forename: Susan
authors.initials: S
authors.lastname: Butler-Wu
authors.affiliation: Departments of Sports Medicine and Orthopaedic Surgery (M.J.L., S.M.R., and F.A.M.) and Microbiology (R.E.B.), Divisions of Allergy and Infectious Diseases (P.S.P.) and Laboratory Medicine and Clinical Microbiology (S.B-W.), University of Washington Medical Center, University of Washington, Box 356500, 1959 N.E. Pacific Street, Seattle, WA 98195. E-mail address for M.J. Lee: jihoon2000@hotmail.com.
authors.forename: Roger E
authors.initials: RE
authors.lastname: Bumgarner
authors.affiliation: Departments of Sports Medicine and Orthopaedic Surgery (M.J.L., S.M.R., and F.A.M.) and Microbiology (R.E.B.), Divisions of Allergy and Infectious Diseases (P.S.P.) and Laboratory Medicine and Clinical Microbiology (S.B-W.), University of Washington Medical Center, University of Washington, Box 356500, 1959 N.E. Pacific Street, Seattle, WA 98195. E-mail address for M.J. Lee: jihoon2000@hotmail.com.
authors.forename: Stacy M
authors.initials: SM
authors.lastname: Russ
authors.affiliation: Departments of Sports Medicine and Orthopaedic Surgery (M.J.L., S.M.R., and F.A.M.) and Microbiology (R.E.B.), Divisions of Allergy and Infectious Diseases (P.S.P.) and Laboratory Medicine and Clinical Microbiology (S.B-W.), University of Washington Medical Center, University of Washington, Box 356500, 1959 N.E. Pacific Street, Seattle, WA 98195. E-mail address for M.J. Lee: jihoon2000@hotmail.com.
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Matsen
mesh_terms: D000328:Adult; D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D004203:Disinfection / Q000379:methods / Q000592:standards*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures; D011300:Preoperative Care / Q000379:methods; D011425:Propionibacterium acnes / Q000187:drug effects / Q000302:isolation & purification*; D018570:Risk Assessment; D012867:Skin / Q000382:microbiology*; D013530:Surgical Wound Infection / Q000382:microbiology / Q000517:prevention & control
chemical_list: D000891:Anti-Infective Agents, Local