RT Journal Article
SR Electronic
T1 Presence of multiple spondyloarthritis (SpA) features is important but not sufficient for a diagnosis of axial spondyloarthritis: data from the SPondyloArthritis Caught Early (SPACE) cohort
JF Annals of the Rheumatic Diseases
JO Ann Rheum Dis
FD BMJ Publishing Group Ltd and European League Against Rheumatism
SP 1086
OP 1092
DO 10.1136/annrheumdis-2016-210119
VO 76
IS 6
A1 Z Ez-Zaitouni
A1 P A C Bakker
A1 M van Lunteren
A1 I J Berg
A1 R Landewé
A1 M van Oosterhout
A1 M Lorenzin
A1 D van der Heijde
A1 F A van Gaalen
YR 2017
UL http://ard.bmj.com/content/76/6/1086.abstract
AB Objectives Concerns have been raised about overdiagnosis of axial spondyloarthritis (axSpA). We investigated whether patients with chronic back pain (CBP) of short duration and multiple SpA features are always diagnosed with axSpA by the rheumatologist, and to what extent fulfilment of the Assessment of SpondyloArthritis International Society (ASAS) axSpA criteria is associated with an axSpA diagnosis.Methods Baseline data from 500 patients from the SPondyloArthritis Caught Early cohort which includes patients with CBP (≥3 months, ≤2 years, onset <45 years) were analysed. All patients underwent full diagnostic workup including MRI of the sacroiliac joints (MRI-SI) and radiograph of sacroiliac joints (X-SI). For each patient, the total number of SpA features excluding sacroiliac imaging and human leucocyte antigen B27 (HLA-B27) status was calculated.Results Before sacroiliac imaging and HLA-B27 testing, 32% of patients had ≤1 SpA feature, 29% had 2 SpA features, 16% had 3 SpA features and 24% had ≥4 SpA features. A diagnosis of axSpA was made in 250 (50%) of the patients: 24% with ≤1 SpA feature, 43% with 2 SpA features, 62% with 3 SpA features and 85% with ≥4 SpA features. Of the 230 patients with a positive ASAS classification 40 (17.4%) did not have a diagnosis of axSpA. HLA-B27 positivity (OR 5.6; 95% CI 3.7 to 8.3) and any (MRI-SI and/or X-SI) positive imaging (OR 34.3; 95% CI 17.3 to 67.7) were strong determinants of an axSpA diagnosis.Conclusions In this cohort of patients with CBP, neither the presence of numerous SpA features nor fulfilment of the ASAS classification criteria did automatically lead to a diagnosis axSpA. Positive imaging was considered particularly important in making a diagnosis of axSpA.