Alternative diagnoses in patients with chronic back pain not diagnosed with axial spondyloarthritis: data from the SPACE cohort

We recently published a study investigating whether the mere presence of multiple spondyloarthritis (SpA) features is sufficient for an axial spondyloarthritis (axSpA) diagnosis.1 Patients (n=500) with chronic back pain (CBP) suspected of axSpA were stratified according to their number of SpA features into four subgroups: ≤1, 2, 3 and ≥4 SpA features based on medical history taking, physical examination and measurement of acute phase reactants, but before sacroiliac imaging and HLA-B27 testing. In total, 24% (38/159), 43% (62/143), 62% (49/79) and 85% (101/119) of CBP patients with ≤1, 2, 3 and ≥4 SpA features, respectively, were diagnosed with axSpA. In particular, HLA-B27 positivity and imaging findings highly suggestive of axSpA were strongly associated with an axSpA diagnosis. Although …