RT Journal Article SR Electronic T1 The link between enthesitis and arthritis in psoriatic arthritis: a switch to a vascular phenotype at insertions may play a role in arthritis development JF Annals of the Rheumatic Diseases JO Ann Rheum Dis FD BMJ Publishing Group Ltd and European League Against Rheumatism SP 992 OP 995 DO 10.1136/annrheumdis-2012-201617 VO 72 IS 6 A1 Sibel Z Aydin A1 Zoe R Ash A1 Ilaria Tinazzi A1 Concepción Castillo-Gallego A1 Chung Kwok A1 Caroline Wilson A1 Mark Goodfield A1 Paolo Gisondi A1 Ai Lyn Tan A1 Helena Marzo-Ortega A1 Paul Emery A1 Richard J Wakefield A1 Dennis G McGonagle YR 2013 UL http://ard.bmj.com/content/72/6/992.abstract AB Objective Subclinical enthesopathy is recognised in both psoriasis and psoriatic arthritis (PsA). This study used ultrasonography with power Doppler (PD) to test the hypothesis that subclinical enthesopathy in PsA was associated with an ‘inflammatory’ or vascular phenotype compared to that seen in psoriasis. Methods 100 patients with a mean age of 46.3 years (SD 15) (42 with psoriasis and 58 with PsA) and 23 matched healthy controls (HC) from two centres were included. 1230 lower limb entheses were scanned by ultrasonographers blinded to clinical details. Both inflammatory and chronic features of enthesopathy were scored. Results Psoriasis patients (with or without arthritis) were more likely to express a vascular phenotype, with higher inflammation-related enthesopathy scores than HC (for inflammation p<0.0001, for chronicity p=0.02, for total ultrasound scores p<0.0001). The PsA patients had higher ultrasound enthesopathy scores than psoriasis patients (inflammation p=0.04, chronicity p=0.02) and HC (inflammation p<0.0001, chronicity p=0.003). When symptomatic entheses were excluded, PsA patients still had higher PD scores than psoriasis patients (p=0.003). Doppler positivity in at least one entheseal site was observed more frequently in PsA (21/58, 36.2%) versus psoriasis (4/42, 9.5%; p=0.002). Conclusions This study shows that the ultrasound appearances of subclinical enthesitis in psoriasis differ from the subclinical enthesitis in PsA, with PsA patients having more PD. This is suggestive of a more inflammatory or vascular process in PsA, and offers potentially novel insights into the progression from skin to joint disease in psoriasis.