OP0257 VALUE OF COLOR DOPPLER ULTRASOUND ASSESSMENT OF SACROILIAC JOINTS IN NON-RADIOGRAPHIC AXIAL SPONDYLOARTHRITIS:A COMPARISON WITH ANKYLOSING SPONDYLITIS
Authors: N. MA, S. Haili
Journal: Annals of the Rheumatic Diseases (2021)

Background: Ultrasound (US) is an accessible imaging technique with a possible role to diagnose active sacroiliitis, so this technique is projected as a promising diagnostic tool for the diagnosis of spondyloarthritis(SpA).The diagnostic value of sacroiliac US has been studied in patients with Ankylosing Spondylitis(AS),becoming a useful and practical tool in comparison with MRI.There are scarce data on the utility of US in the evaluation of Non-radiographic Axial Spondyloarthritis (nr-axSpA). Objectives: The aim of this study is to evaluate the diagnostic utility of color Doppler ultrasound (CDUS) for the detection of sacroiliitis in patients with nr-axSpA and AS. Methods: Patients with nr-axSpA (n=114) and AS(n=80) were enrolled in the study with standardized clinical criteria.According to the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI),nr-axSpA and AS patients were separately divided into active group(n=47,n=43)and inactive group (n=67,n=37).All patients underwent clinical evaluation,and CDUS of sacroiliac joints (SIJs) within the same week. Vascularization, the resistive index (RI) of the SIJs and the first foraminal ramus of the lateral sacral artery were observed and measured by a sonographer who is blinded to initial clinical and radiological assessments. The associated statistics and graphs was utilized to obtain the relationship,which were reflected by the Co-index receiver operating characteristic(ROC)curve or calculating the area under ROC curve(AUC),between the RI of the SIJs and the RI of the first foraminal ramus of the lateral sacral artery in nr-axSpA and AS by using the Logistic Regressive analysis methods,SPSS24.0 and MedCalc19.6.0 software.With MRI-proven sacroiliitis as the diagnostic standard,the Kappa test were used to measure the consistency between the RI of the SIJs and MRI. Results: 1. The RI of the SIJs(AUC=0.855,P&lt;0.001)and Co-index(AUC=0.886,P&lt;0.001)were similar sufficient (Z=1.331, P=0.183) to distinguish the active and inactive group in nr-axSpA .2.The RI of the SIJs(AUC=0.869,P&lt;0.001)and Co-index(AUC=0.893,P&lt;0.001)were also similar sufficient (Z=1.292, P=0.196) to distinguish the active and inactive group in AS .3.Neither of the RI of the first foraminal ramus of the lateral sacral artery in nr-axSpA(AUC=0.748,P&lt;0.001)and AS(AUC=0.674,P=0.003)was outstanding to distinguish the active and inactive group.4.The RI of the SIJs was similar sufficient (Z=0.267,P=0.790) to detect sacroiliitis in nr-axSpA and AS.5. The Co-index was also similar sufficient (Z=0.146, P=0.884) to detect sacroiliitis in nr-axSpA and AS.6.The RI of the SIJs in nr-axSpA and AS showed moderate consistency with MRI(the Kappa values were 0.534 and 0.609,respectively,P&lt;0.01). Conclusion: The RI of the SIJs is a possible role to diagnose active sacroiliitis, so CDUS is projected as a promising diagnostic tool for the diagnosis of nr-axSpA and AS in comparison with MRI. References: [1]Rosa JE, Ruta S, Bravo M, et al. Value of Color Doppler Ultrasound Assessment of Sacroiliac Joints in Patients with Inflammatory Low Back Pain. J Rheumatol. 2019 Jul;46(7):694-700. Disclosure of Interests: None declared