The purpose of the ULISSE study was to evaluate the prevalence of clinical and ultrasonographic (US) entheseal involvement in patients with psoriatic arthritis (PsA), psoriasis, and fibromyalgia syndrome (FMS).
In this cross-sectional multicenter study, patients with PsA and psoriasis (not taking systemic therapy) and FMS underwent a clinical evaluation of the entheses, and a B-mode and power Doppler examination of 6 pairs of entheses.
The study analyzed 140 patients with PsA, 51 with psoriasis, and 51 with FMS. Clinical and US examinations were performed in 1960 and 1680 entheses in the PsA group, and 714 and 612 entheses both in the psoriasis group and in the FMS group. In both per-patient and per-enthesis evaluation, the frequency of entheseal tenderness was higher in patients with FMS (92% of the patients and 46% of the entheses, compared with 66%/23% in the PsA group and 59%/18% in the psoriasis group). With US examination, signs of entheseal involvement were more frequent in both the per-patient and per-enthesis evaluation in PsA and psoriasis (about 90% of patients in both the PsA and psoriasis groups and 75% of patients in the FMS group had at least 1 site affected, and 54%, 41%, and 27% of the pairs of entheses in, respectively, PsA, psoriasis, and FMS patients showed at least 1 enthesis involved).
The ULISSE study indicated that enthesitis is a common feature in patients with PsA, those with psoriasis, and in those with FMS if only clinical examination is used. US entheseal assessment showed findings more consistent with the 3 disorders.