Clinical and Ultrasound Assessment of Enthesis in Psoriatic Arthritis in a Romanian Cohort

Introduction: Spondyloarthritis (SpA) is a group of chronic inflammatory disorders which includes ankylosing spondylitis (SA), psoriatic arthritis (PsA), reactive arthritis (ReA), arthritis associated with inflammatory bowel disease (IBD) and undifferentiated spondyloarthritis (uSpA). The enthesis, the area of insertion of the tendon, ligament or joint capsule onto the bone, can be characterized as a central feature in PsA. Material and methods: The study included a number of 28 patients, 18 females and 10 males, with PsA hospitalized during 2016-2018 in the Department of Rheumatology of the Emergency County Hospital of Craiova. All the patients were diagnosed with psoriatic arthritis according to CASPAR criteria and had a history of entheseal pain, mandatory criteria for inclusion in the study. All patients underwent clinical examination, laboratory tests and musculoskeletal ultrasonography (MSUS). Results: The Belgrade Ultrasound Enthesitis Score (BUSES) was not significantly associated either with ESR (p=0.536) or CRP (p=0.965) values. Furthermore, the clinical evaluation through the LEEDS enthesitis index (LEI) showed no significant association with ESR (p=0.067) or CRP (p=0.206). Despite MSUS and clinical findings, there was no significant correlation between disease activity in psoriatic arthritis (DAPSA) and BUSES (p=0,549) or LEI (p=0,197). However, clinical and echographic scores (BUSES and LEI) were significantly associated (p=0.001). Conclusions: Our study proved a significant correlation between LEI and BUSES, although in literature the evidence is contrasting. This is probably due to the fact that the majority of the patients had high disease activity which made the clinical assessment similar to the US. Further studies on more numerous groups of patients have to be conducted in order to debate the inconsistencies related to clinical and US examinations in patients with PsA.