European League Against Rheumatism recommendations for calcium pyrophosphate deposition. Part I: terminology and diagnosis
- W Zhang1,
- M Doherty1,
- T Bardin2,
- V Barskova3,
- P-A Guerne4,
- T L Jansen5,
- B F Leeb6,
- F Perez-Ruiz7,
- J Pimentao8,
- L Punzi9,
- P Richette2,
- F Sivera10,
- T Uhlig11,
- I Watt12,
- E Pascual13
- 1Academic Rheumatology, University of Nottingham, Nottingham, UK
- 2University Paris 7, Fédération de Rhumatologie, Hôpital Lariboisière, Paris, France
- 3Crystal Arthritis Department, State Institute of Rheumatology, Moscow, Russia
- 4Division of Rheumatology, University Hospital of Geneva, Geneva, Switzerland
- 5 Department of Rheumatology, University Medical Centre Nijmegen St Radboud, Nijmegen, The Netherlands
- 6Second Department of Medicine, Centre for Rheumatology Lower Austria, Stockerau, Austria
- 7Sección de Rheumatologia, Hospital de Cruces, Baracaldo, Spain
- 8Department of Rheumatology, Egas Moniz Hospital, Lisbon, Portugal
- 9Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Padova, Italy
- 10Department of Rheumatology, Hospital General de Alicante, Alicante, Spain
- 11Department of Rheumatology, Diakonhjemmet Hospital, Oslo, Norway
- 12Department of Radiology, Leiden University Medical Centre, Leiden, The Netherlands
- 13Sección de Rheumatologia, Hospital General Universitario de Alicante, Alicante, Spain
- Correspondence to Dr Weiya Zhang, Academic Rheumatology, University of Nottingham, Clinical Sciences Building, City Hospital, Nottingham NG5 1PB, UK;
- Accepted 11 November 2010
- Published Online First 7 January 2011
Objectives To agree terminology and to develop recommendations for the diagnosis of calcium pyrophosphate deposition (CPPD).
Methods The European League Against Rheumatism (EULAR) CPPD Task Force, comprising 15 experts from 10 countries, agreed the terms and recommendations for diagnosis of CPPD using a Delphi consensus approach. Evidence was systematically reviewed and presented in terms of sensitivity, specificity and positive likelihood ratio (LR) to support diagnosis; ORs were used for association. Strength of recommendation (SOR) was assessed by the EULAR visual analogue scale.
Results It was agreed that ‘CPPD’ should be the umbrella term that includes acute calcium pyrophosphate (CPP) crystal arthritis, osteoarthritis (OA) with CPPD and chronic CPP crystal inflammatory arthritis. Chondrocalcinosis (CC) defines cartilage calcification, most commonly due to CPPD and detected by imaging or histological examination. A total of 11 key recommendations were generated on the topics of clinical features, synovial fluid (SF) examination, imaging, comorbidities and risk factors. Definitive diagnosis of CPPD relies on identification of SF CPP crystals. Rapid onset inflammatory symptoms and signs are suggestive but not definitive for acute CPP crystal arthritis. Radiographic CC is not highly sensitive or specific, whereas ultrasonography appears more useful (LR=24.2, 95% CI 3.51 to 168.01) for peripheral joints. Recognised risk factors for CPPD include ageing, OA and metabolic conditions such as primary hyperparathyroidism, haemochromatosis and hypomagnesaemia; familial forms are rare. SORs varied from 53 to 99 (maximum 100).
Conclusion New terms for CPPD were agreed and 11 key recommendations for diagnosis of CPPD were developed using research evidence and expert consensus.
Competing interests None.
Funding Financial support was received from the European League Against Rheumatism.
Provenance and peer review Not commissioned; externally peer reviewed.