title: Propionibacterium can be isolated from deep cultures obtained at primary arthroplasty despite intravenous antimicrobial prophylaxis.
abstract: BACKGROUND
  Propionibacterium organisms are commonly recovered from deep cultures obtained at the time of revision arthroplasty. This study sought to determine whether deep cultures obtained at the time of primary arthroplasty can be substantially positive for Propionibacterium despite thorough skin preparation and preoperative intravenous antibiotic prophylaxis.
  
  
  METHODS
  After timely administration of preoperative antibiotics chosen specifically for their activity against Propionibacterium and after double skin preparation, specimens from the dermis, fascia, capsule, synovium, and glenoid tissue were sterilely harvested from 10 male patients undergoing primary shoulder arthroplasty and were submitted for culture for Propionibacterium.
  
  
  RESULTS
  Of the 50 specimens, 7 were positive for Propionibacterium: 3 in each of 2 patients and 1 in 1 patient. The specimen sources having positive anaerobic cultures were the dermis (1 of 10), fascia (2 of 10), synovium (1 of 10), and glenoid tissue (3 of 10). None of these patients had evidence of infection at the time of the arthroplasty.
  
  
  CONCLUSIONS
  Preoperative antibiotics and skin preparation do not always eliminate Propionibacterium from the surgical field of primary shoulder arthroplasty. The presence of these bacteria in the arthroplasty wound may pose a risk of delayed shoulder arthroplasty failure from the subtle type of periprosthetic infection typically associated with Propionibacterium.
authors.affiliation: Department of Orthopedics and Sports Medicine, University of Washington, Seattle, WA, USA. Electronic address: matsen@u.washington.edu.
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Matsen
authors.affiliation: Department of Orthopedics, University of Washington, Seattle, WA, USA.
authors.forename: Stacy M
authors.initials: SM
authors.lastname: Russ
authors.affiliation: Department of Orthopedics, University of Washington, Seattle, WA, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Bertelsen
authors.affiliation: Department of Laboratory Medicine, University of Washington Medical Center, Seattle, WA, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Butler-Wu
authors.affiliation: Department of Medicine, University of Washington Medical Center, Seattle, WA, USA.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Pottinger
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D019072:Antibiotic Prophylaxis; D019643:Arthroplasty, Replacement; D020405:Dermis / Q000382:microbiology; D005205:Fascia / Q000382:microbiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000382:microbiology / Q000601:surgery*; D011424:Propionibacterium / Q000302:isolation & purification*; D016459:Prosthesis-Related Infections / Q000382:microbiology; D012307:Risk Factors; D012785:Shoulder Joint / Q000382:microbiology* / Q000601:surgery*
chemical_list: D000900:Anti-Bacterial Agents
keywords: Propionibacterium; Shoulder arthroplasty; antibiotic prophylaxis; revision