title: Adult-onset Still's disease: still a diagnosis of exclusion. A nested case-control study in patients with fever of unknown origin.
abstract: OBJECTIVE
  Several sets of criteria have been proposed to classify adult-onset Still's disease (AOSD), those of Yamaguchi being the most commonly used. The Yamaguchi criteria demand the exclusion of other conditions. A clinical scale, recently proposed by Crispin et al., but not yet validated, would allow a positive diagnosis of AOSD in a majority of patients, without the need of thorough diagnostic procedures.
  
  
  METHODS
  From a database of 447 patients with classical fever of unknown origin (FUO), collected over a 10-year period (2000-2009) at a general internal medicine department of a university hospital, 22 patients with AOSD according to the Yamaguchi criteria were extracted and compared with 44 controls, matched to index year. Clinical and laboratory parameters were recorded. Sensitivity, specificity and accuracy of the Yamaguchi criteria and of the clinical score were assessed.
  
  
  RESULTS
  Lower age, joint symptoms, rash, throat ache, neutrophilic leukocytosis, and elevated erythrocyte sedimentation rate were the principal characteristics supporting a diagnosis of AOSD in patients with FUO. Sensitivity, specificity, and accuracy of the Yamaguchi criteria were 95% or more. The clinical scale, while being specific (98%), lacked sensitivity (55%) and had lower accuracy (83%).
  
  
  CONCLUSIONS
  In patients with FUO, the Yamaguchi criteria are a time honored and reliable guide to a diagnosis of AOSD. The clinical scale may serve to rule in, rather than to rule out, AOSD. In many patients, Still's disease is still a diagnosis of exclusion.
authors.affiliation: General Internal Medicine, University Hospital Leuven, Leuven, Belgium. steven.vanderschueren@uz.kuleuven.ac.be
authors.forename: Steven
authors.initials: S
authors.lastname: Vanderschueren
authors.forename: Frederik
authors.initials: F
authors.lastname: Hermans
authors.forename: Paul
authors.initials: P
authors.lastname: De Munter
authors.forename: Daniël
authors.initials: D
authors.lastname: Knockaert
mesh_terms: D000328:Adult; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood; D000465:Algorithms; D001219:Aspartate Aminotransferases / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D016208:Databases, Factual / Q000706:statistics & numerical data; D003663:Decision Trees; D003937:Diagnosis, Differential; D005260:Female; D005293:Ferritins / Q000097:blood; D005335:Fever of Unknown Origin / Q000097:blood / Q000175:diagnosis*; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D016706:Still's Disease, Adult-Onset / Q000097:blood / Q000175:diagnosis*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein; D005293:Ferritins; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase