Case-control Study on Dactylitis, Enthesitis, and Anterior Uveitis in Spondyloarthritis Associated with Inflammatory Bowel Diseases: Role of Coexistent Psoriasis

Objective. To evaluate the frequency of dactylitis, enthesitis, and anterior uveitis (AU) in spondyloarthritis (SpA) associated with inflammatory bowel disease (IBD-SpA) compared with other SpA, and to assess the role of associated psoriasis in the occurrence of dactylitis and enthesitis. Methods. In a 12-month case-control study, the frequency of dactylitis and enthesitis in 29 patients with ulcerative colitis (UC) and 59 with Crohn disease (CD) who satisfied the Spondyloarthritis international Society criteria for axial or peripheral SpA was compared with 176 controls, including 97 (55.1%) with psoriatic arthritis (PsA), 47 (26.7%) with ankylosing spondylitis (AS), and 32 (18.2%) with nonradiographic axial SpA (nr-axSpA). The occurrence of these features in IBD-SpA with and without psoriasis was also evaluated. Results. Axial, peripheral, or mixed involvement was observed in 46 (52%), 29 (33%), and 13 (15%) patients, respectively; and 14/88 (16%) had psoriasis. Dactylitis was recorded in 4/88 patients (4.5%) with IBD-SpA and in 30 controls (17.4%; p = 0.008), enthesitis in 16 cases (18.1%) and in 78/176 controls (44.3%; p < 0.001), and AU in 3 patients (3.4%) with IBD-SpA and in 26 controls (14.7%; p = 0.01). No significant differences were found between patients with UC-SpA and those with CD-SpA. Dactylitis and enthesitis were significantly more common in patients with IBD-SpA who also had psoriasis compared to those without skin disease (p = 0.009 and 0.003, respectively). Conclusion. Dactylitis, enthesitis, and AU are significantly less frequent in IBD-SpA compared with other types of SpA. Given the frequent association of psoriasis and IBD, overlooking coexistent skin disease may lead to overestimating the frequency of these features.