Transition phase towards psoriatic arthritis: clinical and ultrasonographic characterisation of psoriatic arthralgia

A novel nomogram to predict psoriatic arthritis in patients with plaque psoriasis

OBJECTIVE

To construct a predictive model for Psoriatic Arthritis (PsA) based on clinical and ultrasonic characteristics in patients with plaque psoriasis (PsP).

PATIENTS AND METHODS

Demographic, clinical, and ultrasound data were collected from patients with PsP and PsA between May 2019 and December 2022.

RESULTS

A total of 212 patients with PsP and 123 with PsA in the training cohort, whereas the validation cohort comprised 91 patients with PsP and 49 with PsA. The multivariate logistic regression identified nail psoriasis (odds ratio [OR] 1.88, 95% CI: 1.07-3.29), synovitis (OR 18.23, 95% CI: 4.04-82.33), enthesitis (OR 3.71, 95% CI: 1.05-13.14), and bone erosion (OR 11.39, 95% CI: 3.05-42.63) as effective predictors for PsA. The area under the curve was 0.750 (95% CI, 0.691-0.806) and 0.804 (95% CI, 0.723-0.886) for the training and validation cohorts, respectively. The Hosmer-Lemeshow goodness-of-fit test showed good consistency for both the training cohort (p  =  0.970) and the validation cohort (p  =  0.967). Calibration curves also indicated good calibration for both cohorts. The DCA revealed that the predictive model had good clinical utility.

CONCLUSIONS

We have developed a quantitative, intuitive, and convenient predictive model based on nail psoriasis, synovitis, enthesitis, and bone erosion to assess the risk of PsA in patients with plaque psoriasis.

Targeting cytokines in psoriatic arthritis

Psoriatic arthritis (PsA) is part of the psoriatic disease spectrum and is characterized by a chronic inflammatory process that affects entheses, tendons and joints. Cytokines produced by immune and non-immune cells play a central role in the pathogenesis of PsA by orchestrating key aspects of the inflammatory response. Pro-inflammatory cytokines such as TNF, IL-23 and IL-17 have been shown to regulate the initiation and progression of PsA, ultimately leading to the destruction of the architecture of the local tissues such as soft tissue, cartilage and bone. The important role of cytokines in PsA has been underscored by the clinical success of antibodies that neutralize their function. In addition to biologic agents targeting individual pro-inflammatory cytokines, signaling inhibitors that block multiple cytokines simultaneously such as JAK inhibitors have been approved for PsA therapy. In this review, we will focus on our current understanding of the role of cytokines in the disease process of PsA and discuss potential new treatment options based on modulation of cytokine function.

Advantages of ultrasound imaging for the early diagnosis of psoriatic arthritis in patients with moderate to severe psoriasis

Background

Psoriatic arthritis (PsA) is an immune-mediated form of chronic inflammatory arthritis associated with psoriasis (PsO). It constitutes a significant comorbidity of PsO and is distinguished by the presence of widespread musculoskeletal inflammation.

Objective

The aim of this study is to precisely detect asymptomatic PsA using ultrasound (US) examinations and to distinguish between various stages of PsO.

Methods

All patients with moderate-to-severe PsO, who consented to undergo musculoskeletal US examinations during their hospitalization between September 2020 and January 2022, were enrolled in the study. We compared patients' demographic characteristics, comorbidities, disease duration, relevant laboratory parameters, and musculoskeletal US findings.

Results

A total of 547 patients with PsO were included in the study, and 114 of them received a diagnosis of PsA. Furthermore, 16.45 % of patients with moderate to severe PsO displayed subclinical PsA. We observed a significantly higher frequency of abnormal US findings in patients with PsA compared to those without PsA, with a sensitivity of 95.61 % and a specificity of 79.22 %. Additionally, the incidence of enthesitis and synovitis varied significantly between PsA and non-PsA patients, and they were identified as independent variables predicting the presence of PsA. Furthermore, the interphalangeal joint, knee joint, and calcaneal tendon were the most frequently affected areas in PsA, as indicated by the observed US changes.

Conclusion

Ultrasound examination proves to be a valuable tool for detecting subclinical PsA, facilitating early screening of the condition. Particular attention should be directed towards changes in the interphalangeal joint, knee joint, and calcaneal tendon when reviewing ultrasound images of asymptomatic patients.

From Psoriasis to Psoriatic Arthritis: Ultrasound Insights Connecting Psoriasis with Subclinical Musculoskeletal Inflammation and the Path to Psoriatic Arthritis

PURPOSE OF REVIEW

This review summarizes the literature about the transition from psoriasis to psoriatic arthritis (PsA), focusing on musculoskeletal ultrasound (MSUS) for detecting subclinical inflammation and its role in diagnosis and triage of high-risk patients.

RECENT FINDINGS

MSUS effectively detects subclinical musculoskeletal inflammation in patients with psoriasis; however, some of these lesions are non-specific and can be found in healthy individuals. Preliminary evidence suggest that subclinical sonographic findings may predict progression to PsA in psoriasis patients. MSUS can also improve referrals' accuracy and its integration in the PsA classification criteria may improve early PsA detection. MSUS is a valuable tool for detecting subclinical abnormalities in psoriasis patients, which indicate an increased likelihood of progressing to PsA. Its integration into referral protocols and clinical use could improve PsA diagnosis. We propose an MSUS-inclusive algorithm for PsA referrals and triage, which requires validation. The potential of early intervention in reducing PsA progression in psoriasis patients with subclinical inflammation remains to be established.

Prevention of Psoriatic Arthritis: The Need for Prospective Studies

Psoriatic arthritis (PsA) is a systemic chronic inflammatory disease that develops in up to 30% of patients with psoriasis. Mixed data variably support the potential ability to "prevent" and/or delay PsA through use of systemic therapies in psoriasis patients. Though intriguing, almost all of these studies are retrospective in nature, and hold substantial limitations and potential biases that challenge the ability to meaningfully interpretation their results. Thus, the authors believe prospective observational and interventional studies are crucial to understanding our ability to truly modify the transition from psoriasis to psoriatic arthritis and delay or prevent PsA onset.

Anatomical pattern of entheseal and synovial fibroblast activation in patients with psoriasis and its risk of developing psoriatic arthritis

OBJECTIVES

To assess the presence and anatomical distribution of activated fibroblasts in the joints and entheses of patients with psoriasis with arthralgia and to test how fibroblast activation visualised by 68gallium-labelled fibroblast activation protein inhibitor-04 (68Ga-FAPI-04)-positron emission tomography (PET)/CT correlates with clinical tenderness, musculoskeletal ultrasound findings and progression to psoriatic arthritis (PsA).

METHODS

We conducted a prospective cohort study in patients with psoriasis and arthralgia who underwent clinical and ultrasound evaluation and whole-body PET/CT imaging with 68Ga-FAPI-04. 68Ga-FAPI-04 uptake at synovial and entheseal sites was assessed by maximal standardised uptake values (SUVmax) and PET/CT Joint Index (JI); logistic regression models were used to investigate its correlation with clinical and ultrasound findings. Survival analyses were performed on patients with at least 6 months of follow-up.

RESULTS

36 patients with psoriasis were enrolled. 68Ga-FAPI-04 uptake was found in 318 (7.9%) joints and 369 (7.3%) entheses in 29 (80.6%) participants, with a mean SUVmax (SD) of 3.2 (1.8) for joints and 2.9 (1.6) for entheses. Large joints and the lower limbs were predominantly affected. A significant positive relationship was found between 68Ga-FAPI-04-PET/CT signal intensity and the 68 tender joint count (SUVmax: p<0.001; PET/CT-JI: p<0.001) and tender entheses count (SUVmax: p<0.001; PET/CT-JI: p=0.002). No correlations were found with ultrasound findings (SUVmax: p=0.969; PET/CT-JI: p=0.720). Patients with relevant synovio-entheseal 68Ga-FAPI-04 uptake showed a statistically significant higher risk of developing PsA (p=0.02), independent of ultrasound findings.

CONCLUSIONS

Patients with psoriasis presenting with arthralgia show localised signs of resident tissue activation in joints and entheses, which are associated with higher risk of developing PsA.

Ultrasonographic Insights into Peripheral Psoriatic Arthritis: Updates in Diagnosis and Monitoring

Psoriatic arthritis (PsA) is a chronic inflammatory arthritis associated with psoriasis, characterized by heterogeneous clinical manifestations and variable disease progression. Ultrasonography has emerged as a valuable tool in the diagnosis and monitoring of PsA, providing real-time visualization of joint and soft tissue abnormalities. This review highlights recent advancements in ultrasonographic techniques for the assessment of PsA, including the identification of typical features, the role of power Doppler imaging in detecting active inflammation, and the potential of ultrasound for guiding treatment decisions. Additionally, we discuss the utility of ultrasound in assessing treatment response and monitoring disease progression in patients with PsA, with a focus on novel imaging modalities. By elucidating the evolving role of ultrasonography in PsA management, this article aims to enhance clinicians' understanding of its utility in facilitating early diagnosis, optimizing treatment strategies, and improving patient outcomes.

Global and regional epidemiology of psoriatic arthritis in patients with psoriasis: A comprehensive systematic analysis and modelling study

OBJECTIVES

To provide a comprehensive analysis and modelling of the global epidemiology of psoriatic arthritis (PsA) in patients with psoriasis.

METHODS

We reviewed and analysed PsA epidemiology studies over the past 45 years. A Bayesian hierarchical linear mixed model was developed to provide comprehensive age- and sex-specific epidemiologic estimates in different countries and regions.

RESULTS

Three hundred and sixty-three studies were systematically reviewed. The incidence of PsA in patients with psoriasis varied from 2.31 per 1000 person-years in the United Kingdom to 74.00 per 1000 person-years in several Western European countries. The global prevalence of PsA in patients with psoriasis is estimated to be 17.58% (3.33%, 43.69%). Regionally, the overall prevalence of PsA in patients with psoriasis varies from 7.62% (4.18%, 12.28%) in Australasia to 26.59% (18.89%, 35.76%) in North America. The Caribbean and Central Latin America also have relatively high prevalence and are estimated at 23.14% (14.06%, 35.17%) and 22.81% (14.36%, 32.25%), respectively. The prevalence of PsA is higher in adults than children (23.93% vs 8.59%) and also slightly higher in females than males (19.14% vs 16.01%).

CONCLUSIONS

This study provides valuable insights into the global epidemiology of PsA. It also serves as a useful resource for researchers in areas lacking relevant studies. These findings have important implications for clinicians managing the course of PsA and for health policymakers in resource allocation.

Risk of developing psoriatic arthritis in psoriasis cohorts with arthralgia: exploring the subclinical psoriatic arthritis stage

OBJECTIVE

Subjects with subclinical psoriatic arthritis (PsA), defined as the presence of arthralgia in psoriasis (PsO), are at higher risk of PsA but scant real-world data exist. Our aims were to (1) estimate the probability of PsA development in subclinical PsA, (2) characterise subclinical PsA symptoms and (3) determine the clinical patterns at PsA diagnosis.

METHODS

Patients with PsO, mainly subclinical PsA, were evaluated longitudinally in two European cohorts. The key outcome was new-onset PsA. Musculoskeletal symptoms including inflammatory and non-inflammatory symptoms before PsA diagnosis were collected. Occurrence of PsA was analysed with survival analysis and cumulative incidence functions (CIFs).

RESULTS

384 patients with PsO were included with a mean follow-up of 33.0 (±20.9) months. 311 of 384 (80.9%) had subclinical PsA with a PsA incidence rate of 7.7 per 100 patient-years. Subclinical PsA displayed a higher risk of PsA development compared with PsO (HR=11.7 (95% CI 1.57 to 86.7), p=0.016). The probability of new-onset PsA estimated by the CIF was 9.4% (95% CI 4.7% to 10.6%) at month 12 and 22.7% (95% CI 17.2% to 28.6%) at month 36. 58.9% of cases reported inflammatory symptoms in the months immediately prior to PsA diagnosis but prior non-inflammatory symptoms were evident in 83.9% prior to PsA diagnosis. Peripheral joint swelling was the predominant PsA presentation pattern (82.1%).

CONCLUSIONS

The probability of PsA development among subclinical PsA was relatively high, emphasising the importance of emergent musculoskeletal symptoms when aiming for PsA prevention. Joint swelling was the dominant feature in new-onset PsA, likely reflecting clinical confidence in recognising joint swelling.

Enthesopathies - Mechanical, inflammatory or both?

Entheses have the challenging task of transferring biomechanical forces between tendon and bone, two tissues that differ greatly in composition and mechanical properties. Consequently, entheses are adapted to withstand these forces through continuous repair mechanisms. Locally specialized cells (mechanosensitive tenocytes) are crucial in the repair, physiologically triggering biochemical processes to maintain hemostasis. When repetitive forces cause "material fatigue," or trauma exceeds the entheses' repair capacity, structural changes occur, and patients become symptomatic. Clinical assessment of enthesopathies mainly depends on subjective reports by the patient and lacks specificity, especially in patients with central sensitization syndromes. Ultrasonography has been increasingly used to improve the diagnosis of enthesopathies. In this article, the literature on how biomechanical forces lead to entheseal inflammation, including factors contributing to differentiation into a "clinical enthesitis" state and the value of ultrasound to diagnose enthesopathies will be reviewed, as well as providing clues to overcome the pitfalls of imaging.

A clinical review of structural damage in psoriatic arthritis for dermatologists: From pathogenesis to ongoing controversies

Psoriatic arthritis (PsA) is a chronic inflammatory disease that often goes unrecognized in patients with psoriasis. As a result, patients may develop significant structural damage before diagnosis and initiation of adequate treatment. Dermatologists are in an unique position to identify early signs and symptoms of PsA. Here, we briefly review the pathogenesis of PsA, differences in PsA presentation within real-world dermatology practice versus rheumatology clinical trials, and imaging modalities that can be used to assess structural damage. We then discuss several ongoing controversies related to prediction, assessment, and treatment of PsA-related structural damage. Debated questions include the following: (1) Does subclinical enthesitis predict progression from psoriasis to PsA?, (2) Does methotrexate inhibit progression of structural damage?, (3) Does structural damage correlate with clinical disease activity?, and (4) Can progression from psoriasis to PsA be prevented? Evidence presented herein suggests that dermatologists, together with rheumatologists, can play important roles in the early diagnosis and treatment of PsA, thereby potentially preventing irreversible structural damage.

The association between sonographic enthesitis with sonographic synovitis and tenosynovitis in psoriatic arthritis patients

OBJECTIVES

To examine the association between sonographic enthesitis with sonographic synovitis and tenosynovitis in PsA patients, and the association between sonographic enthesitis and clinical characteristics.

METHODS

Consecutive PsA patients that fulfilled the ClASsification criteria for Psoriatic ARthritis (CASPAR) were prospectively recruited. Each patient was evaluated by comprehensive clinical and sonographic assessment (greyscale and Doppler), the latter including 52 joints, 40 tendons and 14 entheses [according to MAdrid Sonography Enthesitis Index (MASEI) plus lateral epicondyles] performed by an experienced sonographer blinded to the clinical data. The US enthesitis score was further categorized to inflammatory (hypoechogenicity, thickening, bursitis and Doppler) and structural (enthesophytes/calcifications and erosions) subcategories. Multivariate linear regression models assessed the association between enthesitis and the selected variables.

RESULTS

A total of 158 PsA patients [mean (s.d.) age 52.3 (13) years, 88 (55.7%) females] were analysed. Multivariate linear regression analyses showed a significant association between sonographic enthesitis and sonographic synovitis (β = 0.18, P = 0.008) and between sonographic enthesitis and sonographic tenosynovitis (β = 0.06, P = 0.02). These associations were derived from the enthesitis inflammatory subcategory of the MASEI (P < 0.05). Associations between enthesitis and synovitis were also demonstrated on the level of the elbow, knee and ankle joints (P < 0.05). In addition, sonographic enthesitis was significantly associated with older age, male sex, swollen joint count, CRP level and physical occupation.

CONCLUSIONS

Sonographic enthesitis is associated with sonographic synovitis and tenosynovitis. The severity of sonographic enthesitis may represent a marker for inflammatory activity in other musculoskeletal domains.

Prevalence of Musculoskeletal Symptoms in Patients with Psoriasis and Predictors Associated with the Development of Psoriatic Arthritis: Retrospective Analysis of a US Claims Database

INTRODUCTION

Psoriasis (PsO) is associated with the development of psoriatic arthritis (PsA). Patients with PsO often experience pre-PsA musculoskeletal (MSK) symptoms, leading to potential structural damage and substantial disease burden with impact on function. The objective of this study is to describe prevalence rates and evidence of MSK symptoms, including incidence of comorbid PsA diagnosis, in patients newly diagnosed with PsO and identify factors associated with PsA diagnosis.

METHODS

This retrospective analysis included administrative claims from the Optum Research Database for adult patients with a new PsO diagnosis between January 2008 and February 2019. Eligible patients had ≥ 2 claims for PsO on unique dates, were aged ≥ 18 years at the date of the first claim with a diagnosis of PsO (index date), and had continuous enrollment with medical and pharmacy coverage for 12 months before (baseline period) and ≥ 12 months following the index date. Primary outcomes were incidence of comorbid PsA diagnosis, prevalence of MSK symptoms other than PsA, and evidence of MSK symptoms collected at baseline and assessed in 12-month intervals through 60 months.

RESULTS

Of the 116,203 patients with newly diagnosed PsO, 110,118 were without baseline comorbid PsA. High prevalence rates of MSK symptoms among patients with only PsO were seen at baseline (47.1%), 12 months (48.2%), and 60 months (82.1%). Patient age, baseline MSK symptoms, and baseline MSK symptom-related healthcare utilization were associated with increased hazard of a PsA diagnosis.

CONCLUSION

Increased prevalence rates of MSK symptoms and burden are experienced by patients newly diagnosed with PsO through 60 months of follow-up. Several baseline factors were associated with increased risk of PsA diagnosis.

Can Early Aggressive Treatment of Psoriasis Prevent Psoriatic Arthritis? A Debate at the GRAPPA Annual Meeting

In recent years, a number of studies have examined risk factors for development of psoriatic arthritis (PsA) among patients with PsO. Most recently, 5 studies have examined the effect of biologic therapy on the development of PsA. However, the results have been mixed, with 3 studies suggesting a lower risk for PsA among those using a biologic therapy and 2 suggesting a higher risk for PsA. At the 2022 Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) meeting, Drs. Enrique Soriano and Alexis Ogdie conducted a debate to discuss the arguments for and against the use of biologic therapies in PsO for the purpose of preventing PsA.

The Challenging Differentiation of Psoriatic Arthritis from Other Arthropathies and Nonspecific Arthralgias in Patients with Psoriasis: Results of a Cross-Sectional Rheumatologic Assessment of a Large Dermatologic Cohort

Aiming to identify the potential challenges in the classification of musculoskeletal manifestations in patients with psoriasis (PsO), this study analyzed the outcomes of a cross-sectional rheumatologic assessment of 1057 PsO patients. In total, 209 had a previous diagnosis of psoriatic arthritis (PsA). Out of the remaining 848 subjects, 293 (35%) were classified as suspected PsA cases according to the rheumatologist's judgment and/or Early PsA Screening Questionnaire score (EARP) ≥ 3. However, only 14% received a PsA diagnosis, 49% had a PsA-alternative diagnosis, and the remaining 37% had nonspecific arthralgias. Most of the newly diagnosed PsA patients had a symptoms duration ≥1 year (72%) and moderate disease activity (55%) with active oligoarthritis (85%), dactylitis, or enthesitis (35%) as the most frequent clinical pattern. The most frequent PsA-alternative diagnoses were osteoarthritis and fibromyalgia (44% and 41%). The only factors with significant (p < 0.05) utility in discriminating PsA from other diseases and nonspecific arthralgias were young age and EARP score with a history of morning stiffness, swollen joints, or dactylitis. These results demonstrated a high prevalence of suspected musculoskeletal symptoms in PsO patients, with, however, only a small proportion due to PsA. Close collaboration between the dermatologist and rheumatologist plays a crucial role in the differential diagnosis of PsA, as well as in monitoring nonspecific arthralgias for the potential transition to overt PsA.

Association between biological immunotherapy for psoriasis and time to incident inflammatory arthritis: limitations and opportunities

Psoriatic arthritis (PsA) is a chronic inflammatory immune-mediated disease that affects approximately 30% of psoriasis patients. In most cases, skin disease clearly precedes the musculoskeletal disease. Some studies suggest that targeted treatment may intercept the disease course and prevent psoriasis patients from developing PsA. A recent population-based retrospective analysis in 15 501 psoriasis patients evaluated the association between different biological treatment strategies and time to incident inflammatory arthritis based on data in a US electronic health records database. A cumulative incidence of 2.6 PsA cases per 100 person-years was determined. The multivariable regression analysis revealed a significantly lower risk of developing inflammatory arthritis in patients who had been prescribed interleukin (IL)-12/23 or IL-23 inhibitors compared with tumour necrosis factor (TNF) inhibitor-treated patients, whereas there was no significant difference in risk for patients prescribed inhibitors of IL-17 versus TNF. Although the analysis was based on a large set of clinical data and the findings were rigorously evaluated, there are some limitations in interpretation due to the study design. Prospective clinical trials are missing, and retrospective data analyses from clinical trials or population-based studies show conflicting results. Overall, the recent data on prevention of PsA in patients with psoriasis support the high need to characterise biomarkers of increased risk and perform prospective clinical trials to give a clear guidance on possibilities for disease interception in psoriatic disease.

EULAR points to consider for the definition of clinical and imaging features suspicious for progression from psoriasis to psoriatic arthritis

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: Development, Detection and Prevention: A Scoping Review

Psoriatic arthritis is a heterogenous chronic inflammatory disease that develops over time in some patients with psoriasis. The course of the disease is variable, with a broad clinical spectrum. The management of PsA has changed tremendously over the last decade, thanks to earlier diagnosis, a multidisciplinary approach and progress in pharmacological therapies. Therefore, screening for risk factors and the early signs of arthritis is highly important and recommended. Currently, research is focused on finding soluble biomarkers and developing imaging techniques that can improve the prediction of psoriatic arthritis. Among imaging modalities, ultrasonography seems to be the most accurate in detecting subclinical inflammation. Early intervention is based on the assumption that it is possible to prevent or delay psoriatic arthritis if systemic treatment for psoriasis can be administered early enough. This review article provides an overview of the current perspectives and evidence regarding the diagnosis, management and prevention of psoriatic arthritis.

Central Pain Sensitization in Patients with Chronic Plaque Psoriasis

BACKGROUND

Central sensitization (CS) is a condition characterized by a disproportionate response to pain stimuli, and is associated with chronic pain conditions such as fibromyalgia, but also with inflammatory arthropathies such as rheumatoid arthritis and psoriatic arthritis (PsA). CS has never been investigated in patients with psoriasis. The aim of this study is to investigate CS in patients with chronic plaque psoriasis.

METHODS

This research involved a cross-sectional observational study of adult patients with moderate-to-severe psoriasis consecutively attending the outpatient clinic of the University Hospital of Verona. Demography, measures of disease severity or activity [i.e., Psoriasis Area and Severity Index (PASI), Disease Activity in Psoriatic Arthritis (DAPSA)], diagnosis of PsA, hypertension, and diabetes were collected. Central Sensitization Inventory (CSI), Dermatology Life Quality Index (DLQI), General Anxiety Disorder-7 (GAD-7), and Patient Health Questionnaire-9 (PHQ-9) were administered.

RESULTS

A total of 194 patients, including 115 (59%) men, with mean age of 54 ± 13 years, mean PASI of 12.7 ± 6.7, and mean DAPSA of 14.4 ± 3.8 were included. In total, 134 patients (79%) had only psoriasis while 60 (31%) had psoriasis and PsA; 19 (10%) patients had CSI score ≥ 40, which is the threshold for diagnosing CS. The proportion of CS ≥ 40 was higher in patients with PsA compared with psoriasis (17% versus 7%, p = 0.031). The mean CSI score in patients with PsA was higher compared with those with only psoriasis (27.5 ± 13.5 versus 20.7 ± 13.7, p = 0.002). An association between CSI and DLQI [β = 1.25 (95% CI 0.85-1.66)], PASI [β = 1.22 (95% CI 0.74-1.65)], GAD-7 [β = 2.07 (95% CI 1.69-2.45)] and PHQ-9 [β = 2.16 (95% CI 1.76-2.54)] was found independently from age, gender, diabetes, and PsA.

CONCLUSIONS

Central sensitization may be associated with psoriasis, particularly in those with high PASI, concomitant PsA, anxiety, depression, and severe quality of life impairment.

Seeing is believing: Smart use of musculoskeletal ultrasound in rheumatology practice

Musculoskeletal ultrasonography has become an increasingly valuable tool as a complement to the physical exam in rheumatology practice. Its point-of-care access, low cost, safety, portability, and reliability in trained hands, make this technique especially useful in patients with inflammatory arthritis. Growing evidence has demonstrated the value of musculoskeletal ultrasound in the detection of inflammatory and structural changes in patients with joint pain without obvious joint swelling, in differentiating various inflammatory diagnoses, in the monitoring of inflammatory arthritis, and interventional procedures. The potential role of ultrasound guiding treat-to-target strategies or tapering treatment in inflammatory arthritis requires further research. However, musculoskeletal ultrasound can also have pitfalls and limitations that a clinician should be aware of.

Histone deacetylase inhibitors as a potential new treatment for psoriatic disease and other inflammatory conditions

Collectively known as psoriatic disease, psoriasis and psoriatic arthritis (PsA) are immune-mediated inflammatory diseases in which patients present with cutaneous and musculoskeletal inflammation. Affecting roughly 2-3% of the world's total population, there remains unmet therapeutic needs in both psoriasis and PsA despite the availability of current immunomodulatory treatments. As a result, patients with psoriatic disease often experience reduced quality of life. Recently, a class of small molecules, commonly investigated as anti-cancer agents, called histone deacetylase (HDAC) inhibitors, have been proposed as a new promising anti-inflammatory treatment for immune- and inflammatory-related diseases. In inflammatory diseases, current evidence is derived from studies on diseases like rheumatoid arthritis (RA) and systematic lupus erythematosus (SLE), and while there are some reports studying psoriasis, data on PsA patients are not yet available. In this review, we provide a brief overview of psoriatic disease, psoriasis, and PsA, as well as HDACs, and discuss the rationale behind the potential use of HDAC inhibitors in the management of persistent inflammation to suggest its possible use in psoriatic disease.

18F-sodium fluoride PET-CT visualizes both axial and peripheral new bone formation in psoriatic arthritis patients

PURPOSE

As bone formation is associated with psoriatic arthritis (PsA), positron emission tomography (PET) using a ¹⁸F-Fluoride tracer may enable sensitive detection of disease activity. Our primary aim was to determine the feasibility of whole-body ¹⁸F-sodium fluoride PET-CT in clinically active PsA patients to depict new bone formation (as a reflection of disease activity) at peripheral joints and entheses. Our secondary aim was to describe ¹⁸F-sodium fluoride findings in the axial skeleton.

METHODS

Sixteen patients (female 10/16, age 50.6 ± 8.9 years) with PsA fulfilling CASPAR criteria or with a clinical diagnosis of PsA according to the treating rheumatologist and with ≥ 1 clinically active enthesitis site were included. Of each patient, a whole-body ¹⁸F-sodium fluoride PET-CT scan was performed. All scans were scored for PET-positive lesions at peripheral joints, enthesis sites and the spine. Clinical disease activity was assessed by swollen/tender joint count 44, enthesitis according to MASES and SPARCC scores.

RESULTS

Out of 1088 evaluated joints, 109 joints showed PET enhancement, mainly in the interphalangeal and metatarsal joints of the feet (14/109, 12.9%) and the distal interphalangeal joints of the hands (14/109, 12.9%). PET positivity was found at 44/464 enthesis sites, mainly at the patella tendon insertion (11/44, 25%) and quadriceps tendon insertion (10/44, 22.7%). Of the PET-positive joints and enthesis sites, respectively 18.2% and 29.5% were clinically positive; 81.8% and 70.5% of the PET-positive joints and entheses respectively were clinically asymptomatic. In 11 patients, ≥ 1 axial PET-positive lesion was observed, mainly in the cervical spine.

CONCLUSIONS

New molecular bone formation was observed on ¹⁸F-sodium fluoride PET-CT scans, in all domains in which PsA disease activity can be observed, with a substantial part showing no clinical symptoms.

CLINICAL TRIAL REGISTRATION

EudraCT: 2017-004,850-40, registered on 13 December 2017.

Reducing the Risk of Developing Psoriatic Arthritis in Patients with Psoriasis

Psoriatic arthritis (PsA) is a heterogeneous chronic inflammatory arthritis associated with psoriasis, which may manifest with different domains such as dactylitis, enthesitis, synovitis and spondylitis. The estimated prevalence of PsA in patients with psoriasis ranges widely between 6% and 42%. In most cases, PsA is preceded by skin involvement by an average time of 7-8 years. In the complex patho-mechanisms involved in the transition from psoriasis to PsA, the gut and skin have been proposed as the sites of immune activation triggering or contributing to the development of PsA. In such a transition, a subclinical phase has been identified, characterized by enthesopathy where soluble biomarkers and imaging findings but no clinical symptoms are detectable. Recent studies have provided some evidence that timely treated psoriasis may reduce the risk of developing PsA.

Musculoskeletal Ultrasound to Identify Subclinical Joint and Periarticular Involvement in Patients With Inflammatory Bowel Disease: A Systematic Literature Review

Background

Musculoskeletal ultrasonography identifies subclinical joint and entheseal inflammation, and it might be of value in patients with inflammatory bowel diseases (IBD), which are at higher risk of inflammatory arthropathy and disability. Our aim was to retrieve the evidence on the applications of ultrasound in patients with non-arthropathic IBD.

Methods

Studies enrolling patients with IBD without arthritis, undergoing ultrasound of joints, tendons or entheses were eligible. The outcomes of interest encompassed the frequency of ultrasound-detected lesions, their accuracy in diagnosing arthritis, their prognostic role and sensitivity to change. All study types, excluding case reports, case series and narrative reviews, were included. Search strategies were applied in PubMed and Embase. Abstract and full-texts were evaluated by pairs of reviewers. The risk of bias was evaluated through the Newcastle-Ottawa scale or the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) 2. The protocol was registered in PROSPERO (CRD42021264972).

Results

Out of 2,304 records, eight studies were included, all reporting the frequency of lesions, while only three evaluated also the diagnostic accuracy. All studies had a cross-sectional design, with no evidence on prediction or follow-up. All studies evaluated the entheses, while only three the joints. The most common chronic lesions were entheseal thickening (up to 81.5%) and enthesophytes (67.9%), while entheseal erosions were present in 16%−17% of patients. Among inflammatory lesions, power Doppler was reported in 14%−67% of patients. There were no differences among Crohn's disease or ulcerative colitis and depending on disease activity, while there were contrasting results on different disease durations. When evaluating the diagnostic performance, the best specificity for a diagnosis if IBD was 0.88 (95%CI, 0.8–0.94) for joint abnormalities. Also, the best sensitivity was 0.88 (95%CI, 0.76–0.95) for entheseal lesions. No studies assessed of the combination of lesions. Due to the limited number of studies, meta-analyses were not performed.

Conclusions

Despite the possible value of ultrasound in IBD, there is limited evidence deriving from cross-sectional studies. Longitudinal studies are needed to clarify the role of this technique, while its current placement might be that of complementing clinical assessment, in particular in early intestinal disease.

Psoriatic arthritis

Psoriatic arthritis (PsA) is a type of inflammatory arthritis that is included within the spondyloarthritis, a group of rheumatological diseases characterized by different clinical manifestations and associated comorbidities, that can compromise the quality of life of patients. The diagnosis of PsA is sometimes difficult due to an enormous clinical and radiological variability, including six different domains of involvement: peripheral joint, axial skeleton, skin psoriasis, nail psoriasis, enthesitis and dactylitis. Currently, there are no biomarkers that allow the detection of PsA in patients with psoriasis, so a high level of suspicion is important, mainly by dermatologists, but also by other specialists, such as family doctors. Advances in the knowledge of new immunological mechanisms and joint management by rheumatologists and dermatologists have made it possible to improve the therapeutic approach in patients with PsA.

Asymptomatic sacroiliitis detected by magnetic resonance enterography in patients with Crohn's disease: prevalence, association with clinical data, and reliability among radiologists in a multicenter study of adult and pediatric population

OBJECTIVES

Patients with Crohn's disease (CD) usually undergo magnetic resonance enterography (MRE) for evaluating small bowel involvement. Musculoskeletal symptoms are the most frequent extraintestinal manifestation in inflammatory bowel diseases, especially in CD, with sacroiliitis at imaging occurring in about 6-46% of patients and possibly correlating with axial spondyloarthritis. The primary study aim was to assess the prevalence of sacroiliitis in adult and pediatric patients with CD performing an MRE. We also evaluated the inter-rater agreement for MRE sacroiliitis and the association between sacroiliitis and patients' clinical data.

METHOD

We retrospectively identified 100 adult and 30 pediatric patients diagnosed with CD who performed an MRE between December 2012 and May 2020 in three inflammatory bowel disease centers. Two radiologists assessed the prevalence of sacroiliitis at MRE. We evaluated the inter-rater agreement for sacroiliitis with Cohen's kappa and intraclass correlation coefficient statistics and assessed the correlation between sacroiliitis and demographic, clinical, and endoscopic data (Chi-square and Fisher's tests).

RESULTS

The prevalence of sacroiliitis at MRE was 20% in adults and 6.7% in pediatric patients. The inter-rater agreement for sacroiliitis was substantial (k = 0.62, p < 0.001) in the adults and moderate (k = 0.46, p = 0.011) in the pediatric cohort. Age ≥ 50 years and the time between CD diagnosis and MRE (≥ 86.5 months) were significantly associated with sacroiliitis in adult patients (p = 0.049 and p = 0.038, respectively).

CONCLUSIONS

Sacroiliitis is a frequent and reliable abnormality at MRE in adult patients with CD, associated with the age of the patients ≥ 50 years and CD duration.

Diagnosis and Intervention in Early Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic inflammatory disorder that affects approximately 20–30% of patients with psoriasis. PsA causes deformities and joint damage, impairing quality of life and causing long-term functional disability. Several recent studies demonstrated that early diagnosis and intervention for PsA prevents permanent invalidity. However, the clinical features of PsA vary and are shared with other differential diseases, such as reactive arthritis, osteoarthritis, and ankylosing spondylitis. The common and overlapping features among these diseases complicate the accurate early diagnosis and intervention of PsA. Therefore, this review focuses on the current knowledge of the diagnosis of early PsA and discusses the meaning of early intervention for early PsA.

Improving Imaging Modalities in Early Psoriatic Arthritis: The Role of Ultrasound in Early Diagnosis of Psoriatic Arthritis

Objective: Despite recent advances, early diagnosis of psoriatic arthritis (PsA) remains a challenge in clinical practice. Ultrasound (US) could be a useful tool for the diagnosis and management of PsA. The objective of this review was to determine the role of US in early diagnosis of PsA.

Methods: We have performed a literature review aiming to evaluate studies on US findings in psoriasis and their predictive value of progression to PsA, as well as studies on US features specific for PsA in comparison with other conditions.

Results: A total of 40 studies were included. Sixteen studies assessed US findings in psoriasis, of which only 3 prospectively evaluated the role of US in predicting progression to PsA. Patients with PsA had a greater frequency of US abnormalities, in particular enthesitis and Power Doppler(PD) signal compared to patients with psoriasis only. In the longitudinal studies, psoriatic patients with higher enthesopathy scores at baseline were more likely to progress to PsA. Twenty-four studies evaluated US abnormalities in PsA and compared them to other conditions. Most specific US features that distinguish PsA from psoriasis were PD signal and erosions in joints and entheses. Extra-synovial changes, including peri-tendinous dermal soft tissue oedema with associated PD signal and flexor tendon enthesopathy, as well as thickening of the pulleys in the flexor tendons were highly characteristic for PsA, as they were frequently found in PsA patients, but in none of the RA patients. US-detected entheseal abnormalities in particular erosions and PD signal were more frequent in patients with PsA compared to fibromyalgia.

Conclusion: Despite the wide use of US in PsA, more research is needed to identify predictive factors of progression to PsA in patients with psoriasis, as well as to determine most specific US features that differentiate PsA from other conditions.

Spondyloarthritis in inflammatory bowel disease cohorts: systematic literature review and critical appraisal of study designs

To critically appraise study designs evaluating spondyloarthritis (SpA) phenotypes in patients with inflammatory bowel disease (IBD). A systematic literature review of PubMed, Ovid, Scopus, Cinahl, Medline, Web of Science, and Cochrane databases was performed. Articles published from January 2000 - March 2020 were included if they evaluated the prevalence/incidence of musculoskeletal disease in cohorts of IBD patients. Most of the 69 included studies were clinic based (54/69, 78%), single center (47/69, 68%) and cross-sectional (60/69, 87%). The median prevalence of axial and peripheral SpA in IBD was 5% (range 1 - 46%) and 16% (range 1 - 43%), respectively. In 38 studies that evaluated axial disease in prospectively enrolled patients, inflammatory back pain was analyzed in 53%. SpA classification criteria were used in 68% and imaging was performed in 76%. In 35 studies that evaluated peripheral disease in prospectively enrolled patients, SpA classification criteria were used in 46%. A physical exam was performed in 74%, and it was performed by a rheumatologist in 54% of studies with a physical exam. Sub-phenotypes of peripheral SpA (mono- or oligo-arthritis, polyarthritis, enthesitis, dactylitis) were variably reported. Seventy-four percent of studies did not mention whether osteoarthritis and fibromyalgia had been assessed or excluded. The spectrum of SpA phenotypes in IBD patients remains incompletely characterized. Future studies should focus on standardizing the variables collected in IBD-SpA cohorts and defining musculoskeletal phenotypes in IBD-SpA in order to better characterize this disease entity and advance the field for clinical and research purposes.

Applying Early Intervention Strategies to Autoimmune Skin Diseases. Is the Window of Opportunity Preclinical? A Dermato-Rheumatology Perspective

Many inflammatory skin diseases exhibit a chronic course with unsatisfactory long-term outcomes. Insights into early intervention approaches in other autoimmune contexts could improve the trajectory of lifelong diseases in terms of sustained remission or minimal disease activity, reduced requirement for therapy and medical resource use, and improved QoL. In both rheumatoid arthritis (RA) and psoriatic arthritis (PsA), we have learned that the timing and intensity of early interventions can influence later outcomes. Investigation into early RA, PsA, and systemic lupus erythematosus has shown that the optimal window of opportunity may even extend into asymptomatic preclinical phases of diseases. Notably, early and preclinical diseases may have pathogenic mechanisms and therapeutic targets that differ from those of the established disease. In this paper, we review the literature on these insights and discuss how similar research and therapeutic strategies may be investigated in cutaneous autoimmunity. We highlight the contribution of skin-resident cells to diseases that were previously thought to be initiated in the primary and secondary lymphoid organs of the immune system. We focus on two dermato‒rheumatology conditions-lupus and psoriasis-which share the commonality that effective early cutaneous disease therapy may have far-reaching implications on abrogating potentially severe systemic disease.

Development of a Predictive Model for Screening Patients with Psoriasis at Increased Risk of Psoriatic Arthritis

Introduction

This study aimed to develop a predictive model based on ultrasound variables which can be used to screen patients with psoriasis who are prone to progress to psoriatic arthritis (PsA) in clinical practice.

Methods

This is a cross-sectional study conducted in a single center from October 2018 to November 2020. All subjects (non-PsA group, PsA group, and control group) underwent an ultrasound examination and their ultrasound abnormalities were recorded. On the basis of statistical analysis and clinical experts’ advice, several variables were selected for modelling. We used logistic regression to establish the prediction model. To assess the discrimination and accuracy of this model, internal validation and external validation were performed.

Results

A total of 852 patients with psoriasis but without PsA, 261 patients with PsA, and 86 healthy volunteers were included. Ultimately, the predictive model consisted of six variables, namely hand joint power Doppler (PD) signals (grade 0: OR 2.94, 95% CI 1.94–4.47; grade ≥ 1: OR 109.30, 95% CI 14.35–832.27; P < 0.001), wrist joint synovial thickening (grade 1: OR 1.29, 95% CI 0.69–2.43; grade 2: OR 4.30, 95% CI 1.92–9.65; grade 3: OR 11.05, 95% CI 1.01–120.64; P = 0.001), knee joint PD signals (grade 0: OR 1.01, 95% CI 0.56–1.80; grade ≥ 1: OR 14.77, 95% CI 3.99–54.69; P < 0.001), toe joint PD signals (grade 0: OR 1.18, 95% CI 0.78–1.79; grade ≥ 1: OR 5.74, 95% CI 2.84–11.63; P < 0.001), quadriceps tendon and patellar tendon enthesitis (OR 1.95, 95% CI 1.36–2.78, P < 0.001), Achilles tendon and plantar aponeurosis enthesitis (OR 1.63, 95% CI 1.14–2.32, P = 0.007). C-index for the predictive model was 0.80 (95% CI 0.76–0.83). After bootstrapping validation (1000 times), it was confirmed to be 0.79. The external validation showed the accuracy of the predictive model is 0.87 (95% CI 0.69–0.95).

Conclusion

This study succeeded in developing a predictive model with a high degree of accuracy to predict the risk of PsA in patients with psoriasis.

Psoriatic arthritis often occurs in the population of patients with psoriasis. It brings a huge burden and pain to patients. At present, the diagnosis for psoriatic arthritis is very challenging. Numerous research studies have begun to focus on identifying patients with psoriasis at increased risk of psoriatic arthritis. Among a lot of modalities, ultrasound has been considered as a sensitive and convenient tool for screening early psoriatic arthritis. Our study successfully established a predictive model based on ultrasound variables to screen patients with psoriasis at high risk of transiting to psoriatic arthritis. After internal and external validation, it showed great accuracy and generalizability. We recommend that clinicians perform ultrasound screening of patients with psoriasis in clinical routine and get their risk value of transiting to psoriatic arthritis by using this model. For those patients with a high risk of progression to psoriatic arthritis, clinicians should refer them to a rheumatology department as soon as possible so that they could have access to early and effective management which might bring them good clinical and imaging outcomes.

The Digital Way to Intercept Psoriatic Arthritis

Psoriasis (PsO) and Psoriatic Arthritis (PsA) are chronic, immune-mediated diseases that share common etiopathogenetic pathways. Up to 30% of PsO patient may later develop PsA. In nearly 75% of cases, skin psoriatic lesions precede arthritic symptoms, typically 10 years prior to the onset of joint symptoms, while PsO diagnosis occurring after the onset of arthritis is described only in 15% of cases. Therefore, skin involvement offers to the rheumatologist a unique opportunity to study PsA in a very early phase, having a cohort of psoriatic “risk patients” that may develop the disease and may benefit from preventive treatment. Progression from PsO to PsA is often characterized by non-specific musculoskeletal symptoms, subclinical synovio-entheseal inflammation, and occasionally asymptomatic digital swelling such as painless toe dactylitis, that frequently go unnoticed, leading to diagnostic delay. The early diagnosis of PsA is crucial for initiating a treatment prior the development of significant and permanent joint damage. With the ongoing development of pharmacological treatments, early interception of PsA has become a priority, but many obstacles have been reported in daily routine. The introduction of digital technology in rheumatology may fill the gap in the physician-patient relationship, allowing more targeted monitoring of PsO patients. Digital technology includes telemedicine, virtual visits, electronic health record, wearable technology, mobile health, artificial intelligence, and machine learning. Overall, this digital revolution could lead to earlier PsA diagnosis, improved follow-up and disease control as well as maximizing the referral capacity of rheumatic centers.

Psoriasis to Psoriatic Arthritis: The Application of Proteomics Technologies

Psoriatic disease (PsD) is a spectrum of diseases that affect both skin [cutaneous psoriasis (PsC)] and musculoskeletal features [psoriatic arthritis (PsA)]. A considerable number of patients with PsC have asymptomatic synovio-entheseal inflammations, and approximately one-third of those eventually progress to PsA with an enigmatic mechanism. Published studies have shown that early interventions to the very early-stage PsA would effectively prevent substantial bone destructions or deformities, suggesting an unmet goal for exploring early PsA biomarkers. The emergence of proteomics technologies brings a complete view of all involved proteins in PsA transitions, offers a unique chance to map all potential peptides, and allows a direct head-to-head comparison of interaction pathways in PsC and PsA. This review summarized the latest development of proteomics technologies, highlighted its application in PsA biomarker discovery, and discussed the possible clinical detectable PsA risk factors in patients with PsC.

Musculoskeletal pain in psoriasis - relation to inflammation and additional value of ultrasound in psoriatic arthritis classification

OBJECTIVE

To investigate and compare clinical features and ultrasound signs of inflammation in joints and entheses in patients with psoriasis (PsO) with and without musculoskeletal pain, and the additional value of ultrasound in classification of psoriatic arthritis (PsA). Furthermore, to explore the association between such findings and patient-reported outcomes (PROs) and the performance of screening-questionnaires for identifying patients with PsA.

METHODS

Patients with PsO (n = 126) recruited from a nationwide survey were evaluated at one of four rheumatology departments. The evaluation included clinical examination, laboratory tests, radiography, greyscale (GS) and colour Doppler (CD) ultrasound of 48 joints and 12 entheses, PROs, and four screening-questionnaires for PsA. Patients were classified with Classification for PsA (CASPAR), ultrasound-modified CASPAR, and ultrasound-only criteria.

RESULTS

When subgroups of self-reported pain (63%), no pain (29%) and diagnosed PsA (9%) were compared, patients with pain had higher tenderness-related clinical scores (tender joints, entheses and fibromyalgia points) and ultrasound GS sum-scores, compared with 'no pain' patients. PROs were negligibly-moderately correlated with pain-related clinical scores (Spearman's rho = 0.11-0.59, all patients), and negligibly-weakly with ultrasound sum-scores (rho = 0.01-0.34). More patients could be classified as PsA when ultrasound synovitis/enthesitis was included as entry criterion (ultrasound-modified CASPAR, 66% of all patients) compared with conventional CASPAR (35%) or ultrasound-only criteria (52%). Sensitivities of screening-questionnaires were low for fulfilment of CASPAR (0.23-0.66), ultrasound-modified CASPAR (0.17-0.57), and ultrasound-only (0.20-0.57) criteria.

CONCLUSION

Self-reported pain in PsO is related to ultrasound inflammation. Ultrasound-modified CASPAR criteria identified almost twice as many patients as conventional CASPAR criteria. Screening-questionnaires showed limited value.

Predictors, Risk Factors, and Incidence Rates of Psoriatic Arthritis Development in Psoriasis Patients: A Systematic Literature Review and Meta-Analysis

Background

Agreement on how to identify psoriasis (PsO) patients at risk of developing psoriatic arthritis (PsA) is lacking.

Objective

To identify predictors, risk factors and incidence rate (IR) of PsA development in PsO patients through a systematic literature review (SLR) and meta-analyses (MA).

Methods

MEDLINE, Embase, and Cochrane databases were searched. Cohort studies were used to assess the predictors, while case–control studies for PsA risk factor determination.

Results

We screened 4698 articles for eligibility, and 110 underwent a full reading and 26 were finally included. Among skin and nail phenotypes, PsO severity and nail pitting were selected as predictors of PsA development. Furthermore, PsO patients with arthralgia (pooled RR 2.15 [1.16; 3.99]) and/or with imaging-MSK inflammation (pooled RR 3.72 [2.12; 6.51]) were at high risk of PsA. Higher categories of BMI and a family history of PsA were other predictors. In outpatient-based cohort studies, the IR of PsA per 100 patient-years varied from 1.34 to 17.4.

Limitations

Despite the strength of the overall results, the heterogeneity and the number of the cohort studies could be considered a limitation.

Conclusions

This study provides a tentative profile of the PsO patient at risk of PsA and will help the design of PsA prevention trials.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-021-00378-w.

Early Origins of Psoriatic Arthritis: Clinical, Genetic and Molecular Biomarkers of Progression From Psoriasis to Psoriatic Arthritis

Greater than 90% of patients with psoriatic arthritis (PsA) first develop their arthritis on a background of known psoriasis (Pso). Thus, having skin/nail Pso certainly is an important risk factor for PsA but as PsA develops in <30% of those affected with Pso, the presence of Pso alone is insufficient as a means of identifying which patients with Pso will develop PsA. It is hoped that with further molecular assessment of Pso patients who do not have any evidence of inflammatory musculoskeletal disease compared to those with early PsA features, that the “at risk” profile of Pso patients destined to develop PsA can be refined such that disease prevention studies can be designed and a new era of treatment for PsA can emerge. In this article, the early stages in the development of PsA are outlined and what is currently known about clinical features, genetic factors and soluble or tissue biomarkers associated with the development of PsA in patients with Pso is reviewed in detail. Finally, proposals are outlined regarding the approaches required in order to address this important research area.

Digital Approaches for a Reliable Early Diagnosis of Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic inflammatory disease that develops in up to 30% of patients with psoriasis. In the vast majority of cases, cutaneous symptoms precede musculoskeletal complaints. Progression from psoriasis to PsA is characterized by subclinical synovio-entheseal inflammation and often non-specific musculoskeletal symptoms that are frequently unreported or overlooked. With the development of increasingly effective therapies and a broad drug armamentarium, prevention of arthritis development through careful clinical monitoring has become priority. Identifying high-risk psoriasis patients before PsA onset would ensure early diagnosis, increased treatment efficacy, and ultimately better outcomes; ideally, PsA development could even be averted. However, the current model of care for PsA offers only limited possibilities of early intervention. This is attributable to the large pool of patients to be monitored and the limited resources of the health care system in comparison. The use of digital technologies for health (eHealth) could help close this gap in care by enabling faster, more targeted and more streamlined access to rheumatological care for patients with psoriasis. eHealth solutions particularly include telemedicine, mobile technologies, and symptom checkers. Telemedicine enables rheumatological visits and consultations at a distance while mobile technologies can improve monitoring by allowing patients to self-report symptoms and disease-related parameters continuously. Symptom checkers have the potential to direct patients to medical attention at an earlier point of their disease and therefore minimizing diagnostic delay. Overall, these interventions could lead to earlier diagnoses of arthritis, improved monitoring, and better disease control while simultaneously increasing the capacity of referral centers.

Musculoskeletal Imaging for Dermatologists: Techniques in the Diagnosis and Management of Psoriatic Arthritis

Psoriatic arthritis is an inflammatory condition affecting up to 30% of patients with psoriasis. Patients may experience irreversible joint damage if not treated early, and diagnostic delays of even 6 months are associated with radiographic progression and impaired function. Therefore, early detection and intervention are of critical importance in patients with psoriatic arthritis. Given that psoriasis often precedes symptoms of psoriatic arthritis, dermatologists are uniquely positioned to identify patients with psoriatic arthritis early in their disease course, before permanent damage has occurred. Several screening tools have been developed to help dermatologists identify patients who may have psoriatic arthritis, but these tools may not capture patients with subclinical disease or quantify the type and severity of the underlying tissue insult, which is often the presenting sign of psoriatic arthritis. In these cases, a combination of clinical assessment and musculoskeletal imaging (e.g., ultrasound) is required. This review summarizes three common musculoskeletal imaging techniques used in the diagnosis and management of patients with psoriatic arthritis: conventional radiography, ultrasound, and magnetic resonance imaging. Further understanding of musculoskeletal imaging will assist dermatologists in making treatment decisions and allow them to have a more active role in the detection of psoriatic arthritis.

Imaging in psoriatic arthritis: Status and recent advances

The heterogeneous nature of psoriatic arthritis (PsA), encompassing several domains, with varied presentations brings about considerable challenges in disease evaluation. Prompt diagnosis and targeted therapy have resulted in disease remission being accepted as an attainable goal in PsA. Imaging has played a pivotal role in early diagnosis, better understanding of pathogenesis, monitoring of disease, and as an outcome measurement tool in clinical trials in PsA. Conventional radiography has been the cornerstone of assessing structural damage. With the advent of ultrasound and magnetic resonance imaging, better delineation of the various structures involved in the disease process is possible, thus enabling sensitive assessment of inflammatory and structural pathologies together. In this review, imaging modalities used in routine assessment and clinical trials in PsA will be discussed in detail, focusing on advances over the past 5 years.

Knuckle pads mimic early psoriatic arthritis

Knuckle pads or Garrod's nodes are a rare, non-inflammatory condition. They consist of benign, well-circumscribed fibro-adipose tissue over the small joints of hands and feet. Knuckle pads may be under-diagnosed and mistaken for early arthritis. The rheumatologist should perform an accurate differential diagnosis in which he can be helped by ultrasound and by other colleagues, such as the dermatologist. Ultrasound is considered useful in the assessment of the thickening of the subcutaneous tissue, located usually on the extensor site of proximal interphalangeal and metacarpophalangeal hand joints. Dermoscopy may play a role in detecting epidermal and dermal changes. We hereby report the case of a female patient with knuckle pads mimicking psoriatic arthritis.

Medical imaging examination in psoriasis and early psoriatic arthritis patients: an updated systematic review and meta-analysis

Psoriatic arthritis appears in one in four skin psoriasis patients. Early detection of the presence of joint involvement and early interception of its developments may minimize long-term functional disability, and the radiological methods may be a perfect choice. To summarize and compare different imaging methods for diagnosing early-stage psoriatic arthritis and determine the necessity of joint examination in all psoriasis patients, several electronic databases, including MEDLINE and EMBASE, were searched for English language studies. A specific selection criterion followed the retrieval of studies. Thirteen studies were finally enrolled in the meta-analysis, eight of which compared the bone changes presentat on medical imaging examination between psoriasis patients without psoriatic arthritis and healthy people; three studies focused on differences between psoriatic arthritis patients and free joint involvement psoriasis patients shown on medical imaging tests. Medical imaging examination, including ultrasound (US), high-resolution peripheral quantitative CT scans (HR-pQCT), and magnetic resonance imaging (MRI), can be good choices for detecting the start of asymptomatic joint inflammation in psoriasis patients, which is essential to early detection and interception of joint damage to lower joint deformities and improve the future quality of life for patients. Additionally, the examination for psoriasis patients with arthralgia is also highly recommended.

Tenosynovitis has a high sensitivity for early ACPA-positive and ACPA-negative RA: a large cross-sectional MRI study

OBJECTIVES

Clinically evident tenosynovitis can be seen in established rheumatoid arthritis (RA). Imaging research has recently shown that tenosynovitis at small joints occurs in early RA, contributes to typical RA symptoms (including joint swelling) and is infrequent in healthy controls. Imaging-detectable tenosynovitis is often not recognisable at joint examination, hence its prevalence can therefore be underestimated. We hypothesised that if MRI-detectable tenosynovitis is a true RA feature, the sensitivity for RA is high, in both anti-citrullinated protein antibodies (ACPA)-positive and ACPA-negative RA, and lower in other diseases that are associated with enthesitis (such as spondyloarthritis (SpA) and psoriatic arthritis (PsA)). So far, no large MRI study addressed these questions.

METHODS

Consecutive patients with early arthritis (n=1211) from one healthcare region underwent contrast-enhanced 1.5T MRI of hand and foot at diagnosis. MRIs were scored for synovitis and tenosynovitis by two readers blinded for clinical data. All included patients with ACPA-positive RA (n=250), ACPA-negative RA (n=282), PsA (n=88), peripheral SpA (n=24), reactive arthritis (n=30) and self-limiting undifferentiated arthritis (UA; n=76) were studied. Sensitivity was calculated.

RESULTS

The sensitivity of tenosynovitis in RA was 85%; 88% for ACPA-positive RA and 82% for and ACPA-negative RA (p=0.19). The sensitivity for RA was significantly higher than for PsA (65%; p=0.001), SpA (53%; p<0.001), reactive arthritis (36%; p<0.001) and self-limiting UA (42%; p<0.001). The observed sensitivity of MRI synovitis was 91% in RA and ranged from 83% to 54% in other groups.

CONCLUSIONS

MRI-detected tenosynovitis has a high sensitivity for early ACPA-positive and ACPA-negative RA. This supports that both juxta-articular (tenosynovitis) and intra-articular synovial involvement is characteristic of RA.

Role of joint damage, malalignment and inflammation in articular tenderness in rheumatoid arthritis, psoriatic arthritis and osteoarthritis

OBJECTIVES

To determine whether clinical tenderness can be considered a sign of inflammatory joint activity in patients with rheumatoid arthritis (RA), osteoarthritis (OA) or psoriatic arthritis (PsA) and to assess other possible factors associated with tenderness.

METHODS

Patients diagnosed with RA, PsA and OA underwent clinical and ultrasound examination of wrists and finger joints. Radiographs of the hands were scored for erosions, joint space narrowing (JSN), osteophytes and malalignment. A binary damage score (positive if ≥1 erosion, JSN and/or presence of malalignment) was calculated. Differences in grey scale signs of synovitis and power Doppler (PD) between tender non-swollen (TNS) versus non-tender non-swollen (NTNS) joints were calculated. Disease duration was assessed,<2 years was regarded as early and >5 years as long-standing arthritis.

RESULTS

In total, 34 patients (9 early and 14 long-standing) from patients with RA, 31 patients (7 early and 15 long-standing) with PsA and 30 with OA were included. We found equal frequencies of PD signal between TNS and NTNS joints in RA (p=0.18), PsA (p=0.59) or OA (p=0.96). However, PD had a significant association with tenderness in early arthritis both in RA (p=0.02) and in PsA (p=0.02). The radiographic damage score showed significant association with tenderness in RA (p<0.01), PsA (p<0.01) and OA (p=0.04).

CONCLUSION

Tenderness might not always be a sign of active inflammation in RA, PsA and OA. While tenderness in early arthritis may be more related to inflammation, established disease is better explained by joint damage and malalignment.

Recent Advances in Imaging for Diagnosis, Monitoring, and Prognosis of Psoriatic Arthritis

Psoriatic arthritis (PsA) is an inflammatory condition characterized by a strong heterogeneity and multifaceted behavior. PsA manifests in two types—axial and peripheral—which may be present at the same time. Peripheral manifestations can be further divided into the articular (arthritis) and extra-articular (i.e., enthesitis and dactylitis) subgroups. In such a complex disease, imaging is often required to characterize the type of involvement and to evaluate the radiological damage and progression of PsA. In addition, imaging plays a pivotal role in clinical practice; that is, for axial involvement. Conventional radiology has been the main standard of reference for many years. However, in recent years, there has been growing interest in different imaging modalities, such as ultrasonography (US) and magnetic resonance imaging (MRI). All these techniques play a role in the diagnosis and follow-up of patients with PsA and cover all the types of the disease. US and MRI have good sensitivities and specificities for detecting synovitis, and this may be helpful for differential diagnosis with other musculoskeletal diseases and useful in the early or preclinical phases of the disease. However, US is not useful in the diagnosis of axial PsA. In addition, other modalities have been investigated in the field of PsA imaging. Computed tomography (CT), in particular, dual energy-CT and high-resolution peripheral CT (HRpQ-CT) might play an important role in the assessment of bone damage, erosions, and new bone formation. Regarding advanced functional imaging, FDG PET/CT is another interesting technique for exploring disease activity.

Defining Pre-Clinical Psoriatic Arthritis in an Integrated Dermato-Rheumatology Environment

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.

Imaging in the diagnosis and management of peripheral psoriatic arthritis

Psoriatic arthritis is a heterogenous disease affecting peripheral and axial joints, tendons, ligaments, and their insertions, in addition to the skin and the nails. The complexity of the involved structures has puzzled clinicians trying to understand the underlying pathology that leads to symptoms in order to choose the appropriate medications with different modes of actions. Imaging, mainly ultrasound and magnetic resonance imaging, allows of accurate detection of inflammatory changes in the musculoskeletal structures, which helps to avoid false positive and negative assessments. The linking of different anatomical structures' involvement using imaging also provides insights into the pathogenesis of psoriatic arthritis. In this review, ultrasound and magnetic resonance imaging will be discussed in depth with regard to their use in the field of peripheral psoriatic arthritis, with a focus on the literature from the last 4 years and recent advances.

Innovative Imaging Technique for Visualization of Vascularization and Established Methods for Detection of Musculoskeletal Inflammation in Psoriasis Patients

Psoriasis (PsO) is one of the common chronic inflammatory skin diseases. Approximately 3% of the European Caucasian population is affected. Psoriatic arthritis (PsA) is a chronic immune-mediated disease associated with PsO characterized by distinct musculoskeletal inflammation. Due to its heterogeneous clinical manifestations (e.g., oligo- or polyarthritis, enthesitis, dactylitis, and axial inflammation), early diagnosis of PsA is often difficult and delayed. Approximately 30% of PsO patients will develop PsA. The responsible triggers for the transition from PsO only to PsA are currently unclear, and the impacts of different factors (e.g., genetic, environmental) on disease development are currently discussed. There is a high medical need, recently unmet, to specifically detect those patients with an increased risk for the development of clinically evident PsA early to initiate sufficient treatment to inhibit disease progression and avoid structural damage and loss of function or even intercept disease development. Increased neoangiogenesis and enthesial inflammation are hypothesized to be early pathological findings in PsO patients with PsA development. Different disease states describe the transition from PsO to PsA. Two of those phases are of value for early detection of PsA at-risk patients to prevent later development of PsA as changes in biomarker profiles are detectable: the subclinical phase (soluble and imaging biomarkers detectable, no clinical symptoms) and the prodromal phase (imaging biomarkers detectable, unspecific musculoskeletal symptoms such as arthralgia and fatigue). To target the unmet need for early detection of this at-risk population and to identify the subgroup of patients who will transition from PsO to PsA, imaging plays an important role in characterizing patients precisely. Imaging techniques such as ultrasound (US), magnetic resonance imaging (MRI), and computerized tomography (CT) are advanced techniques to detect sensitively inflammatory changes or changes in bone structure. With the use of these techniques, anatomic structures involved in inflammatory processes can be identified. These techniques are complemented by fluorescence optical imaging as a sensitive method for detection of changes in vascularization, especially in longitudinal measures. Moreover, high-resolution peripheral quantitative CT (HR-pQCT) and dynamic contrast-enhanced MRI (DCE-MRI) may give the advantage to identify PsA-related early characteristics in PsO patients reflecting transition phases of the disease.