Gout, Hyperuricemia and Crystal-Associated Disease Network (G-CAN) consensus statement regarding labels and definitions for disease elements in calcium pyrophosphate crystal deposition (CPPD)
Year: 2026
Type: article
Abstract: OBJECTIVES: A systematic literature review (SLR) of publications from 2000 to 2022 identified terminology for calcium pyrophosphate crystal deposition (CPPD) and revealed substantial heterogeneity and poor adherence to recommendations. This study aimed to standardise CPPD terminology by developing an international consensus on labels and definitions. METHODS: Members of the Gout, Hyperuricemia and Crystal-Associated Disease Network (G-CAN) were invited by email to participate in a 3-round Delphi exercise. A steering committee identified key components of CPPD aetiology, pathophysiology, and clinical presentation among elements appearing in >10% of SLR papers, adding or removing items when scientifically justified. Participants selected preferred labels for each element. Respondents to the first round were invited to subsequent rounds. This paper reports the resulting G-CAN CPPD nomenclature. RESULTS: Consensus was reached for 'calcium pyrophosphate (CPP) crystal' and 'calcium pyrophosphate crystal deposition (CPPD)' to describe the deposition process. The unified term 'calcium pyrophosphate crystal deposition on imaging' was adopted across imaging modalities, whereas 'chondrocalcinosis' was redefined as conventional radiographic cartilage calcification consistent with CPPD. Four clinical manifestations were identified: 'acute CPP crystal arthritis' (with 'flare' for acute episodes), 'chronic CPP crystal arthritis', 'crowned dens syndrome', and 'osteoarthritis with CPPD'; the term 'pseudogout' received no support. The condition is now classified as 'asymptomatic CPPD' or 'CPPD disease' for symptomatic presentations. CONCLUSIONS: This G-CAN nomenclature is the first systematic effort to align CPPD terminology with contemporary biological and imaging evidence. By resolving longstanding ambiguities-particularly regarding 'chondrocalcinosis'-it provides a framework for consistent research definitions, clinical trial homogeneity, and improved patient care.
Source: Annals of the Rheumatic Diseases
Authors: Georgios Filippou, Laura Pezzoni, Emilio Filippucci, Sara K. Tedeschi, Tristan Pascart, Antonella Adinolfi, Edoardo Cipolletta, Charlotte Jauffret, Silvia Sirotti, Abhishek Abhishek, Daniel Albert, Mariano Andres, Herbert Baraf, Fabio Becce, Jessica Bertrand, Edyta Biernat-Kaluza, Geraldo da Rocha Castelar-Pinheiro, Mats Dehlin, Cesar Diaz-Torne, Michael Doherty, Theodore R. Fields, John FitzGerald, Rada Gancheva, Rebecca Grainger, Nitin Kumar, Timothy Kwok, Augustin Latourte, Jean Liew, Worawit Louthrenoo, Peter Mandl, Tobias Manigold, Geraldine McCarthy, Ingrid Möller, Esperanza Naredo, Tuhina Neogi, Tom Niessink, Sébastien Ottaviani, Konstantinos Parperis, Fernando Perez-Ruiz, Carlos Pineda, Francesco Porta, Edward Roddy, Ann Rosenthal, Naomi Schlesinger, Francisca Sivera, Lisa Stamp, Vicky Tai, Anne-Kathrin Tausche, Lene Terslev, Patapong Towiwat, Till Uhlig, Florentin Ananu Vreju, Congcong Yin, Robert Terkeltaub, Nicola Dalbeth
Institutions: University of Milan, IRCCS Ospedale Galeazzi - Sant'Ambrogio, Marche Polytechnic University, Brigham and Women's Hospital, Harvard University, Université Catholique de Lille, Groupe Hospitalier de l'Institut Catholique de Lille, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, University of Nottingham, Université de Lille, Evaluation des technologies de santé et des pratiques médicales, Dartmouth College, Universitat de Miguel Hernández d'Elx, Hospital General Universitario de Alicante Doctor Balmis, Instituto de Investigación Sanitaria y Biomédica de Alicante (ISABIAL), George Washington University, Centre Hospitalier Universitaire Vaudois, University of Lausanne, University Hospital Magdeburg, Otto-von-Guericke-Universität Magdeburg, Universidade do Estado do Rio de Janeiro, University of Gothenburg, Hospital de Sant Pau, Hospital for Special Surgery, University of California, Los Angeles, University Hospital St. Ivan Rilski, Health New Zealand, University of Otago, University of Michigan, Michigan Medicine, University of Toronto, Sunnybrook Research Institute, Inserm, Université Paris Cité, Assistance Publique – Hôpitaux de Paris, Bioscar, Hôpital Lariboisière, Boston University, Chiang Mai University, Ludwig Boltzmann Institute for Arthritis and Rehabilitation, Medical University of Vienna, University of Bern, University Hospital of Bern, University College Dublin, Mater Misericordiae University Hospital, Universitat de Barcelona, Hospital Universitario Fundación Jiménez Díaz, Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Crystal Consulting (Germany), Hôpital Bichat-Claude-Bernard, University of Cyprus, Osakidetza, Hospital de Cruces, Instituto Nacional de Rehabilitación, Midlands Partnership NHS Foundation Trust, Medical College of Wisconsin, University of Utah, Hospital General de Elda, University of Auckland, University Hospital Carl Gustav Carus, Technische Universität Dresden, University of Copenhagen, Rigshospitalet, Naresuan University, Diakonhjemmet Hospital, University of Medicine and Pharmacy of Craiova, Henry Ford Health, Henry Ford Hospital, University of California San Diego
Language: English
Subfield: Nephrology
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $4,870
OpenAlex ID: W7164025362