title: Fever of unknown origin: a retrospective study of 52 cases with evaluation of the diagnostic utility of FDG-PET/CT.
abstract: OBJECTIVE
  Fever of unknown origin (FUO) is dynamic in its origin and will be an ongoing challenge to the clinician because of shifting disease epidemiology. Here we present a series of patients with classical FUO admitted to an infectious diseases department during a 5-y period, with an emphasis on the diagnostic utility of ¹⁸F-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) in present-day cases of FUO.
  
  
  METHODS
  Patient records were reviewed retrospectively.
  
  
  RESULTS
  A final diagnosis was achieved for 31 of the 52 cases (60%). The final diagnoses of these 31 cases and their distribution in the respective diagnostic categories were: infections 32% (10/31), non-infectious inflammatory disease 55% (17/31), and malignancy 13% (4/31). In our study PET/CT successfully identified an infectious, inflammatory, or neoplastic cause of fever in 10 of the 22 patients (45%) who underwent this scan.
  
  
  CONCLUSIONS
  During the past decade the proportion of non-infectious inflammatory diseases in FUO series has increased. Based on our findings we recommend: (1) a PET/CT scan be performed early in the diagnostic work-up of patients with FUO, and (2) restraint in performing invasive procedures in patients with FUO in whom no cause of fever has been determined during diagnostic work-up.
authors: Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark. tingemannp@hotmail.com
authors: Thomas Ingemann
authors: TI
authors: Pedersen
authors: Casper
authors: C
authors: Roed
authors: Lene Surland
authors: LS
authors: Knudsen
authors: Annika
authors: A
authors: Loft
authors: Peter
authors: P
authors: Skinhoj
authors: Susanne Dam
authors: SD
authors: Nielsen
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005335:Fever of Unknown Origin / Q000000981:diagnostic imaging* / Q000209:etiology*; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007239:Infections / Q000150:complications*; D007249:Inflammation / Q000150:complications*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D009369:Neoplasms / Q000150:complications*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18