Background:Joints and entheseal involvement is a common extraintestinal manifestation in inflammatory bowel diseases (IBD) [1]. Recent studies have shown the superiority of ultrasound over clinical findings in the evaluation of joints and periarticular tissues.Objectives:To assess of joint and entheseal involvement in IBD patients using ultrasound with Power Doppler, their correlation with IBD clinical variables and the difference between Crohn’s disease (CD) and ulcerative colitis (UC).Methods:We prospectively included 38 IBD patients into the study. Disease activity was evaluated in CD by Harvey Bradshaw, in UC - Mayo Index. Peripheral joints and entheses were imaged by ultrasound, using Samsung Accuvix A30 5-13 MHz linear array transducer. Ultrasound examination of 14 peripheral joints (hip, knee, ankle, shoulder, acromioclavicular, elbow, wrist) and 35 entheses was performed. Vascularization on them was assessed with Power Doppler (PD). Entheseal abnormalities were scored with US according to indices GUESS, MASEI and BUSES [2]. Statistical analysis was done by Mann-Whitney test and Spearman criteria by “Statistica” software.Results:In 38 patients UC was in 22 (58%), CD - in 16 (42%). The mean age of UC patients was 28 (23; 35) years, in CD - 33 (27; 36) years. The mean duration of UC was 24 (10; 48) months; CD - 66 (24; 114) months. The majority of patients had highly active disease: in UC - moderate and severe attacks in 16 pts (72%), in CD out of 16 patients, moderate and severe activity was observed in 9 (56%).Synovitis were found in 19 patients (50%), 8 patients with UC (36%), and 10 patients with CD (62%), synovitis with vascularization was detected in 7 patients (18%), five with CD (13%), two with UC (9%).Enthesitis (echogenicity reduction and thickening) was detected in 30 patients (79%), 8 (50%) pts with CD and 17 (77%) pts with UC, enthesitis with vascularization (PD) in 13 pts (34 %), 5 (31%) pts with CD and 8 (36%) pts with UC. Tenosynovitis was observed in 11 pts (29%), three (19%) with CD and 8 (36%) pts - UC, tenosynovitis with vascularization in two patients (5%), one with UC and one with CD. Structure damage (erosion, enthesophytis) were found in 23 patients (61%), 12 patients (75%) with CD and 11 (50%) patients with UC.There were no significant differences in ultrasound signs of joint and entheses damage between patients with UC and CD.We found an association between the clinical characteristics of IBD and the ultrasound signs of entheses damage: duration of the disease has a direct moderate correlation with the number of enthesitis (SR = 0.36; p = 0.026) and GUESS (SR = 0.37; p = 0.022).There was no statistically significant relationship between the severity of the attack and damage to the joints and entheses.Conclusion:The severity of joint and periarticular tissues damage is significantly correlated with the duration of the index disease and are independent of IBD activity.References:[1]The First European Evidence-based Consensus on Extra-Intestinal Manifestations in IBD // JCC. — 2016. —V. 10, № 3. — Р. 239-254.[2] Bandinelli F, Milla M, Genise S et al. Ultrasound discloses entheseal involvement in inactive and low active inflammatory bowel disease without clinical signs and symptoms of spondyloarthropathy. Rheumatology (Oxford). 2011 Jul; 50 (7): 1275-1279.Disclosure of Interests:None declared