Objective. Dermatologists usually see patients with psoriasis before arthritis develops, making them well placed to diagnose early PsA (ePsA). This study aimed to develop a rapid and robust screening questionnaire for predicting PsA in patients with psoriasis referred to a specialized joint dermatology–rheumatology combined clinic. Methods. In all, 228 psoriasis patients naïve to DMARD treatment were administered two screening questionnaire: the new Early ARthritis for Psoriatic patients (EARP) questionnaire and the existing Psoriatic Arthritis Screening and Evaluation (PASE) questionnaire. The diagnostic accuracy of the two questionnaires for the diagnosis of ePsA was compared by receiving operating characteristics curves. Results. After psychometric analysis, a simplified questionnaire of 10 items was found to have good internal reliability (Cronbach's α = 0.83) and was much faster and simpler to administer than the PASE. Both the EARP and PASE questionnaires presented similar receiving operating characteristics curves (specificity 91.6 and 67.2 and sensitivity 85.2 and 90.7, respectively) in identifying ePsA patients by using the cut-off value of 3 for EARP-10 and the standard cut-off value of 44 for PASE. The CASPAR criteria for PsA were present in 61 (26.7%) of the patients at clinical presentation and in 32.9% at 1-year follow-up, and the EARP score of ≥3 correlated with clinically determined arthropathy by a rheumatologist. Conclusion. The EARP questionnaire is simple and fast to administer and proved robust for the identification of PsA in the dermatological setting. Dermatologists should consider the EARP for patients attending clinics, as it correlates well with early PsA diagnosis.

Background The transition from psoriasis (PsO) to psoriatic arthritis (PsA) and the early diagnosis of PsA is of considerable scientific and clinical interest for the prevention and interception of PsA. Objective To formulate EULAR points to consider (PtC) for the development of data-driven guidance and consensus for clinical trials and clinical practice in the field of prevention or interception of PsA and for clinical management of people with PsO at risk for PsA development. Methods A multidisciplinary EULAR task force of 30 members from 13 European countries was established, and the EULAR standardised operating procedures for development for PtC were followed. Two systematic literature reviews were conducted to support the task force in formulating the PtC. Furthermore, the task force proposed nomenclature for the stages before PsA, through a nominal group process to be used in clinical trials. Results Nomenclature for the stages preceding PsA onset, 5 overarching principles and 10 PtC were formulated. Nomenclature was proposed for three stages towards PsA development, namely people with PsO at higher risk of PsA, subclinical PsA and clinical PsA. The latter stage was defined as PsO and associated synovitis and it could be used as an outcome measure for clinical trials evaluating the transition from PsO to PsA. The overarching principles address the nature of PsA at its onset and underline the importance of collaboration of rheumatologists and dermatologists for strategies for prevention/interception of PsA. The 10 PtC highlight arthralgia and imaging abnormalities as key elements of subclinical PsA that can be used as potential short-term predictors of PsA development and useful items to design clinical trials for PsA interception. Traditional risk factors for PsA development (ie, PsO severity, obesity and nail involvement) may represent more long-term disease predictors and be less robust for short-term trials concerning the transition from PsO to PsA. Conclusion These PtC are helpful to define the clinical and imaging features of people with PsO suspicious to progress to PsA. This information will be helpful for identification of those who could benefit from a therapeutic intervention to attenuate, delay or prevent PsA development.

Psoriatic arthritis is a systemic inflammatory disease in which enthesitis and dactylitis are two of the main hallmarks of the disease. In the last years, ultrasonography is increasingly playing a key role in the diagnosis of psoriatic arthritis and ultrasonography of the entheses, particularly of the lower limbs, is commonly used to assess patients with that disease. New advancements in ultrasound equipment using high frequencies probes allowed us also to identify and characterize the involvementof the entheses of the hand in psoriatic arthritis, confirming the results of the experimental models of the disease and the theory of the sinovial-entheseal complex, even in small joints.

Objectives The main objective was to generate a GLobal OMERACT Ultrasound DActylitis Score (GLOUDAS) in psoriatic arthritis and to test its reliability. To this end, we assessed the validity, feasibility and applicability of ultrasound assessment of finger entheses to incorporate them into the scoring system. Methods The study consisted of a stepwise process. First, in cadaveric specimens, we identified enthesis sites of the fingers by ultrasound and gross anatomy, and then verified presence of entheseal tissue in histological samples. We then selected the entheses to be incorporated into a dactylitis scoring system through a Delphi consensus process among international experts. Next, we established and defined the ultrasound components of dactylitis and their scoring systems using Delphi methodology. Finally, we tested the interobserver and intraobserver reliability of the consensus- based scoring systemin patients with psoriatic dactylitis. Results 32 entheses were identified in cadaveric fingers. The presence of entheseal tissues was confirmed in all cadaveric samples. Of these, following the consensus process, 12 entheses were selected for inclusion in GLOUDAS. Ultrasound components of GLOUDAS agreed on through the Delphi process were synovitis, tenosynovitis, enthesitis, subcutaneous tissue inflammation and periextensor tendon inflammation. The scoring system for each component was also agreed on. Interobserver reliability was fair to good (κ 0.39–0.71) and intraobserver reliability good to excellent (κ 0.80–0.88) for dactylitis components. Interobserver and intraobserver agreement for the total B-mode and Doppler mode scores (sum of the scores of the individual abnormalities) were excellent (interobserver intraclass correlation coefficient (ICC) 0.98 for B-mode and 0.99 for Doppler mode; intraobserver ICC 0.98 for both modes). Conclusions We have produced a consensus-driven ultrasound dactylitis scoring system that has shown acceptable interobserver reliability and excellent intraobserver reliability. Through anatomical knowledge, small entheses of the fingers were identified and histologically validated.

In excess of three quarters of patients with psoriatic arthritis (PsA) have preceding psoriasis (PsO), which offers a clinical biomarker for the recognition of early PsA. Numerous surveys have shown a remarkably high frequency of clinically occult musculoskeletal symptoms in psoriasis patients. Imaging studies, particularly ultrasound, show a high prevalence of subclinical enthesitis and other inflammatory changes in psoriasis subjects. Since a serum biomarker, such as the case of anti-citrullinated protein antibodies (ACPA) in rheumatoid arthritis, neither exists nor seems biologically plausible at this point, this article explores how integration of rheumatological and dermatological assessment can be facilitated for the early recognition of potential PsA. Given that scalp disease is a PsA predictor, but may be managed in the community, then a particular need to access this group is needed. An integrated approach between rheumatology and dermatology can involve joint clinics, parallel clinics with discussion of relevant cases or virtual contact between specialties. Early therapy evaluation and integrated strategies have considerable implications for minimizing suffering and joint damage in PsA.