title: Bacterial diversity in suspected prosthetic joint infections: an exploratory study using 16S rRNA gene analysis.
abstract: Formation of biofilm is a prominent feature of prosthetic joint infections (PJIs) and constitutes a challenge to current sampling procedures and culture practices. Molecular techniques have a potential for improving diagnosis of biofilm-adapted, slow-growing and non-culturable bacteria. In this exploratory study we investigated the bacterial diversity in specimens from 22 patients clinically suspected of having PJIs. Bacteriological cultures were performed according to standard practice. A total of 55 specimens from 25 procedures ('specimen sets') were submitted to broad range 16S rRNA gene PCR, cloning, sequencing and phylogenetic analysis. More than 40 bacterial taxa within six phyla were identified in 14 specimen sets originating from 11 patients. Direct observation of biofilm was made in selected specimens by fluorescence in situ hydridization. 16S rRNA gene analysis and bacteriological cultures were concordant for 15/25 specimen sets (60%; five positive, 10 negative); additional taxa were detected in four sets by gene analysis, and discrepant results were obtained for six sets, five of which were negative on culture. Polymicrobial communities were revealed in 9/14 sets by gene analysis and 1/10 sets by culture (P < 0.05). Although our study was not conclusive, these findings are consistent with a primary role of biofilm formation in PJIs.
authors.affiliation: Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Aalborg, Denmark.
authors.forename: Yijuan
authors.initials: Y
authors.lastname: Xu
authors.forename: Vibeke Børsholt
authors.initials: VB
authors.lastname: Rudkjøbing
authors.forename: Ole
authors.initials: O
authors.lastname: Simonsen
authors.forename: Christian
authors.initials: C
authors.lastname: Pedersen
authors.forename: Jan
authors.initials: J
authors.lastname: Lorenzen
authors.forename: Henrik Carl
authors.initials: HC
authors.lastname: Schønheyder
authors.forename: Per Halkjaer
authors.initials: PH
authors.lastname: Nielsen
authors.forename: Trine Rolighed
authors.initials: TR
authors.lastname: Thomsen
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics*; D018407:Bacterial Physiological Phenomena; D001431:Bacteriological Techniques / Q000379:methods; D044822:Biodiversity; D018441:Biofilms / Q000254:growth & development; D016000:Cluster Analysis; D060085:Coinfection / Q000382:microbiology; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D006801:Humans; D007595:Joint Prosthesis / Q000382:microbiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016459:Prosthesis-Related Infections / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S