title: Sonication cultures of explanted components as an add-on test to routinely conducted microbiological diagnostics improve pathogen detection.
abstract: The purpose of this study was to improve the pathogen detection in prosthetic joint infections, particularly to evaluate the feasibility of the sonication culture method in the clinical routine. Explanted components of all patients with presumptive prosthetic or implant infection were sonicated separately in sterile containers to dislodge the adherent bacteria from the surfaces and cultured. The results of sonication culture were compared to the conventional tissue culture. We investigated 60 consecutive patients with loosening of the prostheses or implants Forty patients had septic and 20 aseptic loosening (24 knee prostheses, 21 hip prostheses, 6 mega-prostheses, 2 shoulder prostheses, 6 osteosynthesis, 1 spinal instrumentation). The sensitivity of sonication fluid culture was 83.3%, of single positive tissue culture was 72.2% and 61.1% when two or more cultures yielded the same microorganism. In patients receiving antibiotic therapy the sensitivity was 65.9%, 57.5%, and 42.5%, respectively. Pathogens detected in a single tissue culture as well as in sonication culture yielded a significantly higher rate of prosthetic infection than conventional tissue culture alone (p = 0.008), even in patients receiving continuous antibiotic therapy before explantation (p = 0.016). The sonication method represents an essential add-on in pathogen detection compared to conventional tissue culture.
authors.affiliation: Department of Orthopaedic Surgery, Medical University of Vienna, General Hospital, Vienna, Austria. johannes.holinka@meduniwien.ac.at
authors.forename: Johannes
authors.initials: J
authors.lastname: Holinka
authors.forename: Leonhard
authors.initials: L
authors.lastname: Bauer
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Hirschl
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Graninger
authors.forename: Reinhard
authors.initials: R
authors.lastname: Windhager
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Presterl
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001419:Bacteria / Q000254:growth & development / Q000302:isolation & purification; D001431:Bacteriological Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007595:Joint Prosthesis / Q000382:microbiology*; D008297:Male; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000175:diagnosis* / Q000188:drug therapy / Q000382:microbiology; D012680:Sensitivity and Specificity; D013010:Sonication; D013582:Synovial Fluid / Q000382:microbiology; D046509:Tissue Culture Techniques
chemical_list: D000900:Anti-Bacterial Agents