Full Papers
Magnetic resonance imaging assessment of ASAS-defined active sacroiliitis in patients with inflammatory back pain and suspected axial spondyloarthritis: a study of reliability
L. Cereser1, A. Zabotti2, G. Zancan3, L. Quartuccio4, C. Cicciò5, I. Giovannini6, S. De Vita7, C. Zuiani8, R. Girometti9
- Institute of Radiology, Department of Medicine, University of Udine, University Hospital S. Maria della Misericordia, Udine, Italy.
- Rheumatology Clinic, University of Udine, University Hospital S. Maria della Misericordia, Udine, Italy. alen.zabotti@asufc.sanita.fvg.it
- Institute of Radiology, Department of Medicine, University of Udine, University Hospital S. Maria della Misericordia, Udine, Italy.
- Rheumatology Clinic, University of Udine, University Hospital S. Maria della Misericordia, Udine, Italy.
- Department of Diagnostic Imaging and Interventional Radiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy.
- Rheumatology Clinic, University of Udine, University Hospital S. Maria della Misericordia, Udine, Italy.
- Rheumatology Clinic, University of Udine, University Hospital S. Maria della Misericordia, Udine, Italy.
- Institute of Radiology, Department of Medicine, University of Udine, University Hospital S. Maria della Misericordia, Udine, Italy.
- Institute of Radiology, Department of Medicine, University of Udine, University Hospital S. Maria della Misericordia, Udine, Italy.
CER13684
2021 Vol.39, N°6
PI 1331, PF 1337
Full Papers
PMID: 33635212 [PubMed]
Received: 11/06/2020
Accepted : 27/10/2020
In Press: 15/02/2021
Published: 25/11/2021
Abstract
OBJECTIVES:
The main purpose was to investigate the intra- and inter-rater reliability of the Assessment of SpondyloArthritis international Society (ASAS) definition of positive MRI for active sacroiliitis (ASAS-positive MRI), in a sample of patients with inflammatory back pain (IBP) and suspected axial spondyloarthritis (axSpA), who underwent sacroiliac joints (SIJ) MRI. We also evaluated the intra- and inter-rater reliability for the detection of the recently ASAS-refined findings indicating inflammatory activity.
METHODS:
We retrospectively identified 105 consecutive patients with IBP and suspected axSpA who underwent SIJ MRI. Two radiologists in two distinct reading sessions assessed the prevalence of ASAS-positive MRI and of ASAS-defined signs of inflammatory activity. We determined the intra-rater and inter-rater reliability of the above-mentioned variables by means of prevalence-adjusted bias-adjusted kappa (PABAK) statistic, and verified whether there was any significant difference in providing the diagnosis of ASAS-positive MRI on an inter-rater basis (McNemar test).
RESULTS:
We observed substantial reliability in assessing a SIJ MRI as ASAS-positive both on intra-rater basis (PABAK ranging 0.70–0.77) and inter-rater basis (PABAK 0.71 for the first reading, and 0.64 for the second reading). No significant difference in the rate of diagnosis between raters was found (p>0.99 for both reading sets). Intra-rater and inter-rater reliability for inflammatory activity signs ranged from moderate to almost perfect.
CONCLUSIONS:
The substantial intra- and inter-rater reliability in assessing the ASAS-positive MRI supports its use for classification purposes. The variable reliability of inflammatory activity signs suggests they are suboptimal as a complement to the current definition of ASAS-positive MRI.
