title: Sonication of removed hip and knee prostheses for diagnosis of infection.
abstract: BACKGROUND
  Culturing of samples of periprosthetic tissue is the standard method used for the microbiologic diagnosis of prosthetic-joint infection, but this method is neither sensitive nor specific. In prosthetic-joint infection, microorganisms are typically present in a biofilm on the surface of the prosthesis. We hypothesized that culturing of samples obtained from the prosthesis would improve the microbiologic diagnosis of prosthetic-joint infection.
  
  
  METHODS
  We performed a prospective trial comparing culture of samples obtained by sonication of explanted hip and knee prostheses to dislodge adherent bacteria from the prosthesis with conventional culture of periprosthetic tissue for the microbiologic diagnosis of prosthetic-joint infection among patients undergoing hip or knee revision or resection arthroplasty.
  
  
  RESULTS
  We studied 331 patients with total knee prostheses (207 patients) or hip prostheses (124 patients); 252 patients had aseptic failure, and 79 had prosthetic-joint infection. With the use of standardized nonmicrobiologic criteria to define prosthetic-joint infection, the sensitivities of periprosthetic-tissue and sonicate-fluid cultures were 60.8% and 78.5% (P<0.001), respectively, and the specificities were 99.2% and 98.8%, respectively. Fourteen cases of prosthetic-joint infection were detected by sonicate-fluid culture but not by prosthetic-tissue culture. In patients receiving antimicrobial therapy within 14 days before surgery, the sensitivities of periprosthetic tissue and sonicate-fluid culture were 45.0% and 75.0% (P<0.001), respectively.
  
  
  CONCLUSIONS
  In this study, culture of samples obtained by sonication of prostheses was more sensitive than conventional periprosthetic-tissue culture for the microbiologic diagnosis of prosthetic hip and knee infection, especially in patients who had received antimicrobial therapy within 14 days before surgery.
authors: Division of Infectious Diseases, Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
authors: Andrej
authors: A
authors: Trampuz
authors: Kerryl E
authors: KE
authors: Piper
authors: Melissa J
authors: MJ
authors: Jacobson
authors: Arlen D
authors: AD
authors: Hanssen
authors: Krishnan K
authors: KK
authors: Unni
authors: Douglas R
authors: DR
authors: Osmon
authors: Jayawant N
authors: JN
authors: Mandrekar
authors: Franklin R
authors: FR
authors: Cockerill
authors: James M
authors: JM
authors: Steckelberg
authors: James F
authors: JF
authors: Greenleaf
authors: Robin
authors: R
authors: Patel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000890:Anti-Infective Agents / Q000627:therapeutic use; D001419:Bacteria / Q000302:isolation & purification; D001431:Bacteriological Techniques / Q000379:methods*; D003937:Diagnosis, Differential; D005260:Female; D006622:Hip Prosthesis / Q000009:adverse effects / Q000382:microbiology*; D006801:Humans; D007720:Knee Prosthesis / Q000009:adverse effects / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000175:diagnosis* / Q000382:microbiology; D012680:Sensitivity and Specificity; D013010:Sonication
chemical_list: D000890:Anti-Infective Agents