Clinical assessment and ultrasonography in the follow-up of enthesitis in patients with spondyloarthritis: a multicenter ultrasound study in daily clinical practice

Objectives: The aim of this study was to compare the clinical Maastricht Ankylosing Spondylitis Enthesitis Score (MASIES) and an established ultrasound enthesitis score following treatment change in patients with spondyloarthritis and enthesitis with respect to the sensitivity to change and health-related quality of life. Materials and methods: About 145 patients with active ankylosing spondylitis (n=65), psoriatic arthritis without (n=66) or with (n=14) axial involvement undergoing intensification of their treatment were included in this multicenter study. At baseline, after 3 and 6 months, 13 entheses were scored by MASES, ultrasonography was performed for 14 entheses. Assessments of clinical, laboratory and patient-reported outcome measurements were performed. Results: During 6 months of follow-up, MASES was reduced from 5.57 to 3.12 (P<0.001), which was similar to the reduction of the power Doppler sum score from 5.47 to 2.88 (P<0.001). Both MASES and power Doppler ultrasound were responsive at the 3-month follow-up visit, as indicated by a high sensitivity to change in patients initiating anti-tumor necrosis factor treatment (-0.96 for MASES and -0.74 for power Doppler ultrasound). Improvement of enthesitis did not correlate with patient-reported outcomes. Conclusion: Clinical assessment by MASES and power Doppler sonography as well reflects anti-tumor necrosis factor treatment response in patients with spondyloarthritis. Improvement of enthesitis did not correlate with changes in quality of life measures.