title: PCR-hybridization after sonication improves diagnosis of implant-related infection.
abstract: OBJECTIVE
  We wanted to improve the diagnosis of implant-related infection using molecular biological techniques after sonication.
  
  
  METHODS
  We studied 258 retrieved implant components (185 prosthetic implants and 73 osteosynthesis implants) from 126 patients. 47 patients had a clinical diagnosis of infection (108 components) and 79 patients did not (150 components). The fluids from sonication of retrieved implants were tested in culture and were also analyzed using a modified commercial PCR kit for detection of Gram-positive and Gram-negative bacteria (GenoType BC; Hain Lifescience) after extraction of the DNA.
  
  
  RESULTS
  38 of 47 patients with a clinical diagnosis of infection were also diagnosed as being infected using culture and/or PCR (35 by culture alone). Also, 24 patients of the 79 cases with no clinical diagnosis of infection were identified microbiologically as being infected (4 by culture, 16 by PCR, and 4 by both culture and PCR). Comparing culture and PCR, positive culture results were obtained in 28 of the 79 patients and positive PCR results were obtained in 35. There were 21 discordant results in patients who were originally clinically diagnosed as being infected and 28 discordant results in patients who had no clinical diagnosis of infection.
  
  
  CONCLUSIONS
  For prosthetic joint infections and relative to culture, molecular detection can increase (by one tenth) the number of patients diagnosed as having an infection. Positive results from patients who have no clinical diagnosis of infection must be interpreted carefully.
authors.affiliation: Department of Clinical Microbiology, IIS-Fundacion Jimenez Diaz, Madrid, Spain. jestebanmoreno@gmail.com
authors.forename: Jaime
authors.initials: J
authors.lastname: Esteban
authors.forename: Noelia
authors.initials: N
authors.lastname: Alonso-Rodriguez
authors.forename: Gema
authors.initials: G
authors.lastname: del-Prado
authors.forename: Alberto
authors.initials: A
authors.lastname: Ortiz-Pérez
authors.forename: Diana
authors.initials: D
authors.lastname: Molina-Manso
authors.forename: Jose
authors.initials: J
authors.lastname: Cordero-Ampuero
authors.forename: Enrique
authors.initials: E
authors.lastname: Sandoval
authors.forename: Ricardo
authors.initials: R
authors.lastname: Fernández-Roblas
authors.forename: Enrique
authors.initials: E
authors.lastname: Gómez-Barrena
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015342:DNA Probes; D005593:Fracture Fixation, Internal; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis; D006801:Humans; D008875:Middle Aged; D009181:Mycoses / Q000175:diagnosis; D016133:Polymerase Chain Reaction / Q000379:methods; D019736:Prostheses and Implants; D016459:Prosthesis-Related Infections / Q000175:diagnosis*; D013010:Sonication / Q000379:methods*; D013530:Surgical Wound Infection / Q000175:diagnosis*; D055815:Young Adult
chemical_list: D015342:DNA Probes