RT Journal Article
SR Electronic
T1 Evaluation of the performances of ‘typical’ imaging abnormalities of axial spondyloarthritis: results of the cross-sectional ILOS-DESIR study
JF RMD Open
JO RMD Open
FD EULAR
SP e000918
DO 10.1136/rmdopen-2019-000918
VO 5
IS 1
A1 Anna Molto
A1 Laure Gossec
A1 Marie-Martine Lefèvre-Colau
A1 Violaine Foltz
A1 Romain Beaufort
A1 Jean-Denis Laredo
A1 Pascal Richette
A1 Philippe Dieude
A1 Philippe Goupille
A1 Antoine Feydy
A1 Maxime Dougados
YR 2019
UL http://rmdopen.bmj.com/content/5/1/e000918.abstract
AB Objective To evaluate the prevalence and performance as axial Spondyloarthritis (axSpA) diagnostic feature of radiographic and MRI lesions ‘typical’ of axSpA of the sacroiliac joint (SIJ) and spine in a mechanical chronic back pain (CBP) population and in an axSpA cohort.Methods Cross-sectional multicentre study. Patients: (1) recent onset axSpA (DESIR cohort) and (2) mechanical non-axSpA CBP matched for age and gender (ILOS study). Imaging: radiographs and MR scans were performed identically in both groups. All images were centrally read, blinded for diagnosis and for other imaging findings in the same patient. Statistical analysis: prevalence of lesions ‘typical of axSpA’ were compared in both groups. Sensitivity, specificity and positive likelihood ratios (LR+) of each lesion (and combination of lesions) were calculated.Results A total of 98 patients with CBP were included, and compared with 100 patients with recent onset axSpA. SIJ lesions were consistently more frequent in the axSpA group (35.0% vs 11.8% p<0.001, 35.0% vs 8.4% p<0.001% and 32.0% vs 10.0%. p<0.001 for modified New York criteria, MRI sacroiliitis and ≥3 erosions of the SIJ on MRI, respectively), and performed well (LR+ for ≥3 erosions 3.0 (95% CI 1.6 to 5.8)). Spine lesions were comparable across groups: radiographic lesions were rare, while all MRI lesions were frequent.Conclusion Our study confirms that ‘typical’ lesions can also be observed in patients with non-axSpA CBP but that SIJ lesions by all modalities remain the most valuable for diagnosis, including structural lesions of the SIJ. This suggests the potential interest of adding MRI SIJ structural lesions in the definition of MRI abnormalities for axSpA classification.