title: Performance of classification criteria for gout in early and established disease.
abstract: OBJECTIVE
  To compare the sensitivity and specificity of different classification criteria for gout in early and established disease.
  
  
  METHODS
  This was a cross-sectional study of consecutive rheumatology clinic patients with joint swelling in which gout was defined by presence or absence of monosodium urate crystals as observed by a certified examiner at presentation. Early disease was defined as patient-reported onset of symptoms of 2 years or less.
  
  
  RESULTS
  Data from 983 patients were collected and gout was present in 509 (52%). Early disease was present in 144 gout cases and 228 non-cases. Sensitivity across criteria was better in established disease (95.3% vs 84.1%, p<0.001) and specificity was better in early disease (79.9% vs 52.5%, p<0.001). The overall best performing clinical criteria were the Rome criteria with sensitivity/specificity in early and established disease of 60.3%/84.4% and 86.4%/63.6%. Criteria not requiring synovial fluid analysis had sensitivity and specificity of less than 80% in early and established disease.
  
  
  CONCLUSIONS
  Existing classification criteria for gout have sensitivity of over 80% in early and established disease but currently available criteria that do not require synovial fluid analysis have inadequate specificity especially later in the disease. Classification criteria for gout with better specificity are required, although the findings should be cautiously applied to non-rheumatology clinic populations.
authors.affiliation: Department of Medicine, University of Otago, Wellington, New Zealand.
authors.forename: William J
authors.initials: WJ
authors.lastname: Taylor
authors.affiliation: Department of Rheumatology, Radboud University Medical Centre, Nijmegen, Netherlands.
authors.forename: Jaap
authors.initials: J
authors.lastname: Fransen
authors.affiliation: Department of Medicine, University of Auckland, Auckland, New Zealand.
authors.forename: Nicola
authors.initials: N
authors.lastname: Dalbeth
authors.affiliation: Clinical Epidemiology Research and Training Unit, 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: VA Medical Center, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: H Ralph
authors.initials: HR
authors.lastname: Schumacher
authors.affiliation: Department of Medicine, University of Otago, Wellington, New Zealand.
authors.forename: Melanie
authors.initials: M
authors.lastname: Brown
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Worawit
authors.initials: W
authors.lastname: Louthrenoo
authors.affiliation: Servicio de Reumatología, Hospital General de México, México City, México.
authors.forename: Janitzia
authors.initials: J
authors.lastname: Vazquez-Mellado
authors.affiliation: Nasonova Research Institute of Rheumatology of Russia, Moscow, Russia.
authors.forename: Maxim
authors.initials: M
authors.lastname: Eliseev
authors.affiliation: School of Medicine and Medical Science, University College Dublin, Dublin, Ireland Department of Rheumatology, Mater Misericordiae University Hospital, Dublin, Ireland.
authors.forename: Geraldine
authors.initials: G
authors.lastname: McCarthy
authors.affiliation: Department of Medicine, University of Otago, Christchurch, Canterbury, New Zealand.
authors.forename: Lisa K
authors.initials: LK
authors.lastname: Stamp
authors.affiliation: Rheumatology Division, Hospital Universitario Cruces & BioCruces Health Research Institute, Vizcaya, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Perez-Ruiz
authors.affiliation: Department Reumatologia, Hospital General Universitario de Elda, Alicante, Spain.
authors.forename: Francisca
authors.initials: F
authors.lastname: Sivera
authors.affiliation: University of Paris Diderot, Sorbonne Paris Cité, UFR de Médecine, Paris, France INSERM, UMR 1132, Hôpital Lariboisière, Paris, France Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Lariboisière, Service de Rhumatologie, Centre Viggo Petersen, Pôle Appareil Locomoteur, 2, Rue Ambroise Paré, Paris, France.
authors.forename: Hang-Korng
authors.initials: HK
authors.lastname: Ea
authors.affiliation: Department of Rheumatology, Amsterdam Rheumatology Immunology Center (ARC), Westfries Gasthuis, Hoorn, the Netherlands.
authors.forename: Martijn
authors.initials: M
authors.lastname: Gerritsen
authors.affiliation: Epidemiology Unit, Italian Society for Rheumatology (SIR), Milan, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Scire
authors.affiliation: Division of Rheumatology, University and IRCCS Policlinico S. Matteo Foundation, Pavia, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Cavagna
authors.affiliation: Division of Rheumatology and Immunology, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taiwan, ROC.
authors.forename: Chingtsai
authors.initials: C
authors.lastname: Lin
authors.affiliation: Taichung Veterans' General Hospital, Taichung, Taiwan, ROC.
authors.forename: Yin-Yi
authors.initials: YY
authors.lastname: Chou
authors.affiliation: Division of Rheumatology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Dresden, Germany.
authors.forename: Anne-Kathrin
authors.initials: AK
authors.lastname: Tausche
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brasil.
authors.forename: Geraldo
authors.initials: G
authors.lastname: da Rocha Castelar-Pinheiro
authors.affiliation: Department of Rheumatology, Rijnstate Hospital, Arnhem, the Netherlands.
authors.forename: Matthijs
authors.initials: M
authors.lastname: Janssen
authors.affiliation: School of Medicine, China Medical University, Taichung, Taiwan, ROC Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan, ROC.
authors.forename: Jiunn-Horng
authors.initials: JH
authors.lastname: Chen
authors.affiliation: Centre of Rheumatology and Spine Disorders, Copenhagen University Hospital Glostrup, Glostrup, Denmark.
authors.forename: Ole
authors.initials: O
authors.lastname: Slot
authors.affiliation: Research Laboratory and Academic Division of Clinical Rheumatology, Department of Internal Medicine, University of Genova, Genova, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Cimmino
authors.affiliation: National Advisory Unit on Rehabilitation in Rheumatology, Department of Rheumatology, Diakonhjemmet Hospital, Vinderen, Oslo, Norway.
authors.forename: Till
authors.initials: T
authors.lastname: Uhlig
authors.affiliation: Department of Rheumatology, Radboud University Medical Centre, Nijmegen, Netherlands.
authors.forename: Tim L
authors.initials: TL
authors.lastname: Jansen
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000032:analysis; D003430:Cross-Sectional Studies; D042241:Early Diagnosis; D005260:Female; D006073:Gout / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013582:Synovial Fluid / Q000737:chemistry; D013997:Time Factors; D014527:Uric Acid / Q000032:analysis
chemical_list: D015415:Biomarkers; D014527:Uric Acid
keywords: Epidemiology; Gout; Synovial fluid