title: Comparison of cultures and 16S rRNA sequencing for identification of bacteria in two-stage revision arthroplasties: preliminary report.
abstract: BACKGROUND
  The use of a prefabricated spacer in two-stage revision arthroplasty remains one of the few surgery strategies for infected-joint arthroplasty treatment, despite the many unidentified microorganisms in the infected joint replacements reported in some recent studies. The aim of this prospective survey was to investigate if the sonication followed by polymerase chain reaction (PCR) can improve bacterial identification on the surfaces of prefabricated spacers and if the systemic laboratory mediators of infection and positive microbiological results can take a role of predictive factors of infection and clinical failures in 2-years follow-up.
  
  
  METHODS
  Thirteen patients with prosthetic joint infection were investigated. Bacterial culture and deoxyribonucleic acid (DNA) sequencing were used to detect bacteria on the surface of prefabricated spacers removed during the second stage of revision arthroplasty. The results of pre- and intraoperative culture and DNA sequencing were compared. Minimum follow-up was 2 years.
  
  
  RESULTS
  The result of tissue cultures in second-stage revision arthroplasties revealed positive results in 15 % of patients with Coagulase-negative Staphylococci (CNS) growth. Bacterial DNA was found in over 90 % of patients with negative synovial fluid culture. Positive PCR results revealed potential pathogenic bacteria and species of human and environmental microflora with low virulence. Clinical failures at final follow-up were recorded in 2 (16.6 %) patients.
  
  
  CONCLUSIONS
  The lack of clinical signs of infection, negative culture of preoperative joint aspirate, and intraoperative specimens do not exclude the presence of bacteria on the surfaces of spacers. The positive results of sonication and molecular tests should be interpreted as real pathogenicity factors in the light of the clinical and laboratory data, especially for patients with immunodeficiency. We confirmed our previous results that sonication followed by PCR and sequencing improved bacterial identification.
authors.affiliation: Department of Orthopaedic and Traumatology, Medical University of Silesia, School of Medicine in Katowice, Ziołowa 45/47, Katowice, 40-635, Poland. pberez.pb@gmail.com.
authors.forename: Przemysław
authors.initials: P
authors.lastname: Bereza
authors.affiliation: Department of Medical Microbiology, Medical University of Silesia, School of Medicine in Katowice, Katowice, Poland.
authors.forename: Alicja
authors.initials: A
authors.lastname: Ekiel
authors.affiliation: Department of General, Molecular Biology and Genetics, Medical University of Silesia, School of Medicine in Katowice, Katowice, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Auguściak-Duma
authors.affiliation: Department of Medical Microbiology, Medical University of Silesia, School of Medicine in Katowice, Katowice, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Aptekorz
authors.affiliation: Department of Medical Microbiology, Medical University of Silesia, School of Medicine in Katowice, Katowice, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Wilk
authors.affiliation: Department of Orthopaedic and Traumatology, Medical University of Silesia, School of Medicine in Katowice, Ziołowa 45/47, Katowice, 40-635, Poland.
authors.forename: Damian
authors.initials: D
authors.lastname: Kusz
authors.affiliation: Department of Orthopaedic and Traumatology, Medical University of Silesia, School of Medicine in Katowice, Ziołowa 45/47, Katowice, 40-635, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Wojciechowski
authors.affiliation: Department of General, Molecular Biology and Genetics, Medical University of Silesia, School of Medicine in Katowice, Katowice, Poland.
authors.forename: Aleksander L
authors.initials: AL
authors.lastname: Sieroń
authors.affiliation: Department of Medical Microbiology, Medical University of Silesia, School of Medicine in Katowice, Katowice, Poland.|Department of Histology and Embryology, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Gayane
authors.initials: G
authors.lastname: Martirosian
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects* / Q000295:instrumentation; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects* / Q000295:instrumentation; D001419:Bacteria / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D018441:Biofilms; D004269:DNA, Bacterial / Q000235:genetics* / Q000302:isolation & purification; D005260:Female; D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D007720:Knee Prosthesis / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016459:Prosthesis-Related Infections / Q000175:diagnosis* / Q000382:microbiology / Q000601:surgery; D012336:RNA, Ribosomal, 16S / Q000235:genetics* / Q000302:isolation & purification; D012086:Reoperation; D021521:Ribotyping / Q000379:methods*; D013010:Sonication; D013582:Synovial Fluid / Q000382:microbiology; D013997:Time Factors; D014774:Virulence
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S
keywords: 16S Ribosomal RNA; Biofilms; Prosthesis-related infections; Reoperation; Sonication