title: 2015 Gout classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative.
abstract: OBJECTIVE
  Existing criteria for the classification of gout have suboptimal sensitivity and/or specificity, and were developed at a time when advanced imaging was not available. The current effort was undertaken to develop new classification criteria for gout.
  
  
  METHODS
  An international group of investigators, supported by the American College of Rheumatology and the European League Against Rheumatism, conducted a systematic review of the literature on advanced imaging of gout, a diagnostic study in which the presence of monosodium urate monohydrate (MSU) crystals in synovial fluid or tophus was the gold standard, a ranking exercise of paper patient cases, and a multi-criterion decision analysis exercise. These data formed the basis for developing the classification criteria, which were tested in an independent data set.
  
  
  RESULTS
  The entry criterion for the new classification criteria requires the occurrence of at least one episode of peripheral joint or bursal swelling, pain, or tenderness. The presence of MSU crystals in a symptomatic joint/bursa (ie, synovial fluid) or in a tophus is a sufficient criterion for classification of the subject as having gout, and does not require further scoring. The domains of the new classification criteria include clinical (pattern of joint/bursa involvement, characteristics and time course of symptomatic episodes), laboratory (serum urate, MSU-negative synovial fluid aspirate), and imaging (double-contour sign on ultrasound or urate on dual-energy CT, radiographic gout-related erosion). The sensitivity and specificity of the criteria are high (92% and 89%, respectively).
  
  
  CONCLUSIONS
  The new classification criteria, developed using a data-driven and decision-analytic approach, have excellent performance characteristics and incorporate current state-of-the-art evidence regarding gout.
authors.affiliation: Boston University School of Medicine, Boston, Massachusetts, USA.
authors.forename: Tuhina
authors.identifier: http://orcid.org/0000-0002-9515-1711
authors.initials: T
authors.lastname: Neogi
authors.affiliation: Viecuri Medical Center, Venlo, The Netherlands Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Tim L Th A
authors.initials: TL
authors.lastname: Jansen
authors.affiliation: University of Auckland, Auckland, New Zealand.
authors.forename: Nicola
authors.initials: N
authors.lastname: Dalbeth
authors.affiliation: Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Jaap
authors.initials: J
authors.lastname: Fransen
authors.affiliation: University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: H Ralph
authors.initials: HR
authors.lastname: Schumacher
authors.affiliation: Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Dianne
authors.initials: D
authors.lastname: Berendsen
authors.affiliation: University of Otago, Wellington, New Zealand.
authors.forename: Melanie
authors.initials: M
authors.lastname: Brown
authors.affiliation: Boston University School of Medicine, Boston, Massachusetts, USA.
authors.forename: Hyon
authors.initials: H
authors.lastname: Choi
authors.affiliation: University of Florida, Gainesville, Florida, USA.
authors.forename: N Lawrence
authors.initials: NL
authors.lastname: Edwards
authors.affiliation: Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Hein J E M
authors.initials: HJ
authors.lastname: Janssens
authors.affiliation: INSERM UMR 1132, Hôpital Lariboisière, AP-HP, and Université Paris Diderot, Sorbonne Paris Cité, Paris, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Lioté
authors.affiliation: McMaster University Medical Centre, Hamilton, Ontario, Canada.
authors.forename: Raymond P
authors.initials: RP
authors.lastname: Naden
authors.affiliation: University of Edinburgh, Edinburgh, UK.
authors.forename: George
authors.initials: G
authors.lastname: Nuki
authors.affiliation: University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Alexis
authors.initials: A
authors.lastname: Ogdie
authors.affiliation: Hospital Universitario Cruces and BioCruces Health Research Institute, Vizcaya, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Perez-Ruiz
authors.affiliation: University of Alabama at Birmingham, Birmingham, Alabama, USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Saag
authors.affiliation: Birmingham VA Medical Center and University of Alabama at Birmingham, and Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors.forename: Jasvinder A
authors.initials: JA
authors.lastname: Singh
authors.affiliation: Duke University and Duke University Medical Center, Durham, North Carolina, USA Gilead Sciences, Foster City, California, USA.
authors.forename: John S
authors.initials: JS
authors.lastname: Sundy
authors.affiliation: University Hospital Carl Gustav Carus, Dresden, Germany.
authors.forename: Anne-Kathrin
authors.initials: AK
authors.lastname: Tausche
authors.affiliation: Hospital General de Mexico, Mexico City, Mexico.
authors.forename: Janitzia
authors.initials: J
authors.lastname: Vaquez-Mellado
authors.affiliation: University of Michigan Health System, Chelsea.
authors.forename: Steven A
authors.initials: SA
authors.lastname: Yarows
authors.affiliation: University of Otago, Wellington, New Zealand.
authors.forename: William J
authors.initials: WJ
authors.lastname: Taylor
mesh_terms: D003661:Decision Support Techniques; D003952:Diagnostic Imaging / Q000379:methods; D019317:Evidence-Based Medicine / Q000379:methods; D006073:Gout / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007391:International Cooperation; D014057:Tomography, X-Ray Computed
keywords: Arthritis; Gout; Synovial fluid