title: The value of 18F-FDG PET/CT in diagnosing infectious endocarditis.
abstract: OBJECTIVE
  Early detection of infectious endocarditis is challenging. For diagnosing infectious endocarditis, the revised Duke criteria are the gold standard. Evidence of endocardial involvement on echocardiography is a major criterion, but sensitivity and specificity of echocardiography are not optimal. Here we investigated the utility of (18)F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT) to diagnose infectious endocarditis in patients with gram-positive bacteraemia.
  
  
  METHODS
  Seventy-two patients with gram-positive bacteraemia were prospectively included. Patients with a positive blood culture growing Staphylococcus aureus, Streptococcus species or Enterococcus species were eligible when a risk factor for developing metastatic infectious foci was present. Infectious endocarditis was defined according to the revised Duke criteria. All patients underwent (18)F-FDG PET/CT and echocardiography. (18)F-FDG uptake in or around the heart valves was evaluated independently by two nuclear medicine physicians.
  
  
  RESULTS
  Sensitivity for diagnosing infectious endocarditis with (18)F-FDG PET/CT was 39% and specificity was 93%. The positive predictive value was 64% and negative predictive value was 82%. The mortality rate in patients without infectious endocarditis and without increased (18)F-FDG uptake in or around the heart valves was 18%, and in patients without infectious endocarditis but with high (18)F-FDG uptake in or around the heart valves the mortality rate was 50% (p = 0.181).
  
  
  CONCLUSIONS
  (18)F-FDG PET/CT is currently not sufficiently adequate for the diagnosis of infectious endocarditis because of its low sensitivity. Improvements such as patient preparation with low carbohydrate-fat allowed diet and technical advances in the newest PET/CT scanners may increase sensitivity in future studies.
authors.affiliation: Department of Internal Medicine, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands. ilsekouijzer@gmail.com
authors.forename: Ilse J E
authors.initials: IJ
authors.lastname: Kouijzer
authors.forename: Fidel J
authors.initials: FJ
authors.lastname: Vos
authors.forename: Marcel J R
authors.initials: MJ
authors.lastname: Janssen
authors.forename: Arie P J
authors.initials: AP
authors.lastname: van Dijk
authors.forename: Wim J G
authors.initials: WJ
authors.lastname: Oyen
authors.forename: Chantal P
authors.initials: CP
authors.lastname: Bleeker-Rovers
mesh_terms: D016470:Bacteremia / Q000150:complications; D042241:Early Diagnosis; D004696:Endocarditis / Q000150:complications / Q000000981:diagnostic imaging*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006094:Gram-Positive Bacteria / Q000502:physiology; D016908:Gram-Positive Bacterial Infections / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18