AB1116 DOPPLER EVALUATION OF ENTHESITIS SEEMS TO BE A RELEVANT OUTCOME IN THE ASSESSMENT OF ACTIVITY IN SPONDYLOARTHRITIS AND PSORIATIC ARTHRITIS

Background: The assessment of activity in spondyloarthritis (SpA) and psoriatic arthritis (PsA) involves several domains, including enthesitis. Clinical enthesitis evaluation has shown low sensitivity, specificity and reliability. Ultrasound (US) examination of enthesitis can be an accurate and objective way to evaluate this domain, supporting its inclusion in the assessment of the global state of the disease Objectives: The main objective of this study is to analyze de prevalence of Doppler enthesitis in active SpA and PsA patients and to evaluate its association with the disease activity at patient level prior to start a biological therapy Methods: A prospective multicenter cross-sectional study in patients with SpA and PsA with active disease (defined as patients who were going to start or switch biological therapy according to physician criteria and in agreement with clinical guidelines) was undertaken. Basal assessment included clinical features, physical examination and laboratory tests. Patients underwent bilateral US examination of peripheral entheses according to the MAdrid Sonographic Enthesitis Index (MASEI). MASEI and Outcome Measures in Rheumatology (OMERACT) enthesitis Power Doppler (PD) definitions were checked. Each enthesis was scanned in two planes: longitudinal and transverse, and 5 second videos were recorded for reliability. An inter-reader analysis by three readers was performed at each included center. For statistical analysis Mann-WhitneyU and Kruskal-Wallis tests were used. Intraclass correlation coefficient (ICC) and kappa test were used for reliability Results: 64 consecutive patients were included, of whom 19(29.7%) were ankylosing spondylitis (AS), 7(10.9%), non-radiographic axial spondyloarthritis (nr-axSpA) and 38(59.4%) PsA patients. Mean age was 52.4±12.5 years and 36(56.3%) were males. Mean DAS28 (3.6±1.3) for peripheral involvement, mean BASDAI (5.6±2.2) for axial involvement, and CRP values (10±10.9) reflect moderate-high disease activity at baseline. Demographic, clinical and MASEI baseline characteristics are shown in Table 1. Mean global MASEI score was 29.4 (±11.4) and 55 patients (86%) scored ≥18 (proposed cut-off point to diagnose SpA). At the patient level, abnormal US findings consistent with at least one enthesis showing PD signal were observed in 52(81.3%) of patients using MASEI PD and 48(75%) using OMERACT PD definition without significant variation among the different SpA subtypes (p=0.8 and p=0.6, respectively). The inter-reader reliability among the two cohorts from each center performed by three readers was high (ICC cohort 1:0.92; cohort 2:0.85) and inter three readers kappa was good (0.92 and 0.86 for Doppler MASEI and Doppler OMERACT respectively). Conclusion: PD enthesitis is found in the vast majority of patients with active SpA and PsA, independent of SpA subtype. MASEI PD might have some advantages versus OMERACT PD definition to detect active enthesitis. These findings support the usefulness of PD US in the assessment of activity in SpA and PsA at patient level. Disclosure of Interests: Juan Molina Collada: None declared, Cristina Macia-Villa: None declared, Chamaida Plasencia: None declared, Jose-Maria Alvaro-Gracia Grant/research support from: Abbvie, Elli-Lilly, MSD, Novartis, Pfizer, Consultant of: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB, Paid instructor for: Elli-Lilly, Pfizer, Roche, Speakers bureau: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, Gedeon Richter, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB, Eugenio de Miguel Grant/research support from: Yes (Abbvie, Novartis, Pfizer), Consultant of: Yes (Abbvie, Novartis, Pfizer), Paid instructor for: yes (AbbVie, Novartis, Pfizer, MSD, BMS, UCB, Roche, Grunental, Janssen, Sanofi), Speakers bureau: yes (AbbVie, Novartis, Pfizer, MSD, BMS, UCB, Roche, Grunental, Janssen, Sanofi)