title: 16S rDNA sequencing of valve tissue improves microbiological diagnosis in surgically treated patients with infective endocarditis.
abstract: OBJECTIVE
  The aim was to evaluate 16S rDNA sequencing in heart valves in patients with infective endocarditis undergoing surgery.
  
  
  METHODS
  Fifty-seven patients with infective endocarditis were examined in this prospective study by analysing heart valves with 16S rDNA sequencing and culturing methods and comparing the results to blood cultures. As controls, heart valves from 61 patients without any signs of endocarditis were examined.
  
  
  RESULTS
  All together 77% of the endocarditis patients were positive for 16S rDNA, 84% had positive blood cultures and 23% had positive cultures from heart valves, whereas only 16% of the cultures from heart valves were concordant with results from blood cultures or 16S rDNA. Concordant results between 16S rDNA sequencing and blood cultures were found in 75% patients. All controls were negative for 16S rDNA. In 4 out of 9 patients with negative blood cultures, the aetiology was established by 16S rDNA alone, i.e. viridans group streptococci.
  
  
  CONCLUSIONS
  In this Swedish study, 16S rDNA sequencing of valve material was shown to be a valuable addition in blood culture-negative cases. The value of heart valve culture was low. Molecular diagnosis using 16S rDNA sequencing should be recommended in patients undergoing valve replacement for infective endocarditis.
authors: Department of Clinical Microbiology, Karolinska University Hospital and Department of Clinical Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
authors: Martin
authors: M
authors: Vondracek
authors: Ulrik
authors: U
authors: Sartipy
authors: Ewa
authors: E
authors: Aufwerber
authors: Inger
authors: I
authors: Julander
authors: Dan
authors: D
authors: Lindblom
authors: Katarina
authors: K
authors: Westling