MRI and ultrasonography for diagnosis and monitoring of psoriatic arthritis

Relationship of psoriatic arthritis with nail and scalp involvement in Turkish psoriasis patients: Multicentered cross-sectional study

Psoriasis is a common multisystem inflammatory disease, and arthritis is an essential component of the disorder, requiring early diagnosis and prompt treatment for successful management. In this study, we aimed to investigate the relationship between nail and scalp involvement and other covariates with psoriatic arthritis (PsA). This cross-sectional study, conducted from June 2021 through December 2021, included 763 patients from 11 different centers in Turkey. The severity of involvement was evaluated using psoriasis area severity index (PASI), nail psoriasis severity index (NAPSI), and psoriasis scalp severity index (PSSI) scores. Predictors for PsA were evaluated using univariate and multivariate logistic regression models. PsA (n = 155, 21.5%) was significantly more common in patients having a family history of psoriasis (43.2% vs 30.9%, P = .004), nail involvement (68.4% vs 52.3%, P < .001), and coexistence of nail and scalp involvement (53.7% vs 39.6%, P = .002). Furthermore, patients with PsA had considerably higher PASI (7 vs 5.6, P = .006), NAPSI (5 vs 2, P < .001), and PSSI scores (7 vs 4, P = .002) and longer disease duration (months) (126 vs 108, P = .009). In multivariate analysis, female gender [OR: 3.01, 95% CI (1.861-4.880), P < .001], nail involvement [OR: 2.06, 95% CI (1.293-3.302), P = .002)], and body mass index (BMI) [OR: 1.06, 95% CI (1.017-1.100), P = .005] were identified as independent predictors for PsA. Female gender, nail involvement, and high BMI are significant predictors for PsA and warrant detailed rheumatological assessment. Notably, being female is the strongest predictor of increased risk of PsA in our survey. Scalp involvement appears not to be associated with PsA. Also, the presence of PsA seems related to a more severe skin involvement phenotype.

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.

EXPLORing Arthritis with Total-body Positron Emission Tomography

Arthritis has significant adverse consequences on musculoskeletal tissues and often other organs of the body. Current methods for clinical evaluation of arthritis are suboptimal, and biomarkers that are objective and measurable indicators for monitoring of arthritis disease activity are in critical demand. Recently, total-body positron emission tomography (PET) has been developed that can collect imaging signals synchronously from the entire body at ultra-low doses and reduced scan times. These scanners have increased signal collection efficiency that overcomes several limitations of standard PET scanners in the evaluation of arthritis, and they may potentially provide biomarkers to assess local and systemic impact of the arthritis disease process. This article reviews current results from using total-body PET in the assessment of common arthritic conditions, and it outlines future opportunities and challenges.

Efficacy of tofacitinib on enthesitis in patients with active psoriatic arthritis: analysis of pooled data from two phase 3 studies

BACKGROUND

Tofacitinib is an oral Janus kinase inhibitor for the treatment of psoriatic arthritis (PsA). This post hoc analysis assessed tofacitinib efficacy on enthesitis by baseline location and severity, and impact on disease activity and patient-reported outcomes (PROs), in patients with PsA.

METHODS

Data were pooled from two phase 3 studies (NCT01877668/NCT01882439) in patients with PsA receiving tofacitinib 5 or 10 mg twice daily to month (M)6 or placebo to M3. Endpoints were: change from baseline in Leeds Enthesitis Index (LEI) or Spondyloarthritis Research Consortium of Canada Enthesitis Index (SPARCC); proportions of patients with enthesitis, relapsed enthesitis after resolution, de novo enthesitis, low disease activity (LDA) or remission (minimal disease activity/very low disease activity; Psoriatic Arthritis Disease Activity Score; Disease Activity Index for Psoriatic Arthritis, and Composite Psoriatic Disease Activity in Psoriatic Arthritis); and PROs (Functional Assessment of Chronic Illness Therapy-Fatigue [FACIT-F] total and arthritis pain Visual Analog Scale scores). Descriptive statistics were generated by visit and treatment. Change from baseline in PROs was evaluated by multivariate linear regression.

RESULTS

Seven hundred ten patients from two studies were included: 479 had LEI > 0; 545 had SPARCC > 0; and 136 had LEI = 0 and SPARCC = 0 at baseline. At baseline, among patients with LEI > 0 or SPARCC > 0, mean LEI and SPARCC across treatments and enthesitis locations/severities ranged from 1.0-4.4 and 1.3-9.4, respectively. Across several baseline enthesitis locations/severities, changes from baseline in LEI and SPARCC up to M3 were greater with tofacitinib (-2.0-0.4 and -3.5-0.2) vs placebo (-‍0.9-‍0.4 and -1.5-1.1). Enthesitis at M6 was more common in patients with greater baseline enthesitis severity. At M6, ≤ 40% of patients with baseline LEI > 0 or SPARCC > 0 whose enthesitis had resolved by M1/M3 experienced a relapse, and < 14% of patients with baseline LEI = 0 and SPARCC = 0 had de novo enthesitis. LDA/remission rates generally increased with tofacitinib over time. Baseline LEI location was significantly associated with change from baseline in arthritis pain score, while baseline SPARCC severity was significantly associated with change from baseline in FACIT-F total and arthritis pain scores.

CONCLUSION

Tofacitinib treatment resulted in improvements in enthesitis in patients with PsA, regardless of baseline location or severity.

TRIAL REGISTRATION

NCT01877668;NCT01882439.

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.

An overview of psoriatic arthritis including clinical manifestations, assessment, diagnostic criteria, investigations, drug management and GRAPPA guidelines

Psoriatic arthritis (PsA) is a chronic and often progressive inflammatory disease, occurring in up to 30% of patients with psoriasis. Assessment of patients with PsA requires consideration of all disease domains, including peripheral arthritis, axial disease, enthesitis, dactylitis, skin psoriasis, psoriatic nail disease, uveitis and inflammatory bowel disease. Co-morbidities and related conditions should all be considered including: obesity, metabolic syndrome, cardiovascular disease, anxiety/depression, liver disease, chronic infections, malignancy, osteoporosis, fibromyalgia and reproductive health.

Psoriatic arthritis: Ultrasound peculiarities with particular emphasis on enthesitis

The prevalence of psoriatic arthritis among patients with psoriasis has a marked variability with ethnic and geographic variations. Inflammatory changes associated with psoriatic arthritis include bone erosion, tenosynovitis, and synovial hypertrophy, but enthesitis is considered the hallmark. Both X-ray and magnetic resonance imaging (MRI) are usefull in the diagnosis of psoriatic arthritis, but ultrasonography is the best imaging modality to assess entheses. Ultrasound findings of enthesitis include a loss of the regular fibrillar architecture, hypoechoic thickening, hypervascularization of tendons, ligaments, and joint capsules at their bony attachment, bony changes (including irregularities and erosions). Ultrasound has also proved the ability to detect inflammatory subclinical findings and to be useful in the follow-up of therapies.

Consensus-based recommendations on the diagnosis, referral and clinical management of patients with psoriatic arthritis

Psoriatic arthritis (PsA) is a highly heterogeneous disease with complex manifestations. Limited understanding of the disease and non-availability of local guidelines pose challenges in the management of PsA in Saudi Arabia. Therefore, this expert consensus is aimed to provide recommendations on the management of patients with PsA, including referral pathway, definition of remission and treat-to-target (T2T) approach. A Delphi technique of consensus development was used involving an expert panel comprised of 10 rheumatologists, one dermatologist and one family physician. Based on the review of available published evidence and the opinions of clinical experts, key recommendations were developed. A consensus was achieved in defining the following: management guideline adaptable for Saudi Arabia, most useful screening tool, laboratory investigations, imaging tests and criteria for referring suspected PsA patients to a rheumatologist. In addition, an agreement was achieved in defining the T2T strategy and remission for the clinical management of PsA. Overall, these recommendations provide an evidence-based framework for the management of PsA patients in Saudi Arabia.

Whole-Body MRI in Rheumatology: Major Advances and Future Perspectives

Whole-body magnetic resonance imaging is constantly gaining more importance in rheumatology, particularly for what concerns the diagnosis, follow-up, and treatment response evaluation. Initially applied principally for the study of ankylosing spondylitis, in the last years, its use has been extended to several other rheumatic diseases. Particularly in the pediatric population, WB-MRI is rapidly becoming the gold-standard technique for the diagnosis and follow-up of both chronic recurrent multifocal osteomyelitis and juvenile spondyloarthritis. In this review, we analyze the benefits and limits of this technique as well as possible future applications.

Role of ultrasound for assessment of psoriatic arthritis patients with fibromyalgia

OBJECTIVE

To investigate whether ultrasonography (US), as an objective imaging modality, can optimise the evaluation of disease activity in psoriatic arthritis (PsA) patients with concomitant fibromyalgia syndrome (FMS).

METHODS

The study population included 156 consecutive PsA patients who were recruited prospectively and fulfilled the ClASsification criteria for Psoriatic ARthritis criteria. The patients underwent complete clinical evaluation including assessment of fulfilment of the 2016 fibromyalgia classification criteria. All of the patients underwent US evaluation including 52 joints, 40 tendons and 14 entheses. The US score was based on the summation of a semiquantitative score (including synovitis, tenosynovitis and enthesitis). Scoring was performed by a sonographer blinded to the clinical data. Spearman's correlation coefficient and multivariate linear regression models were used to examine the association of FMS with clinical and the US scores.

RESULTS

Forty-two patients (26.9%) with coexisting PsA and FMS were compared with 114 (73.1%) PsA patients without FMS. Patients with PsA and FMS had significantly increased scores for clinical composite indices, including non-Minimal Disease Activity, Composite Psoriatic Disease Activity Index (CPDAI), Disease Activity for Psoriatic Arthritis (DAPSA) and Psoriatic Arthritis Disease Activity Score (PASDAS) (p<0.001). In contrast, the total US score and its subcategories were similar for those with and without FMS. The total US score significantly correlated with CPDAI, DAPSA and PASDAS (p<0.001) in the PsA without FMS but not in the PsA with FMS group. FMS was significantly associated with higher clinical scores (p<0.001) but not with the US score (multivariable linear regression models).

CONCLUSIONS

US has significantly greater value than composite clinical scores in the assessment of disease activity in PsA patients with FMS.

Three-Dimensional Structure Analysis of Mouse Nails using Synchrotron Radiation

Until now, studies on nail disease have been performed through microscopic diagnosis and microscopic computed tomography (micro-CT). However, these kinds of conventional methods have some limitations. Firstly, the microscopic method is considered the gold standard for medical diagnosis. However, due to the use of fluorescent materials, the sample is damaged and it takes a long time to get results. Secondly, while micro-CT is a non-invasive method to get inner structure images of the sample with high resolution, the penetration and spatial resolution are insufficient for studying the microstructures of the sample, such as the sponge bone and the muscle fibers. In contrast, synchrotron radiation (SR) X-ray imaging technology has the advantage of very vividly demonstrating the anatomic structure of the sample with high penetration, sensitivity, and resolution. In this study, we compared the optical microscopic method using hematoxylin and eosin (H&E) staining and SR imaging to analyze the nail tissue in a mouse model. The results showed that SR could depict the inner structures of a mouse nail without physical damage. Additionally, we could divide the important anatomical structures nail unit into three parts with three-dimensional images: the nail bed, nail matrix, and hyponychium. The images showed that SR could be used for analyzing nails by visualizing the relatively clear and medically semantic structures in a three-dimensional section. We expect that the results of this study will be applied to study nail diseases and pharmaceutical research on their treatment.

Concepts, Role, and Advances on Nail Imaging

This review discusses, from a practical point of view, the most common imaging techniques and their applications in nail pathologies with some technical considerations. There are several imaging techniques for studying the nail, and all of them require proper devices and trained operators. The highest axial resolution and a more extensive range of applications are provided by ultrasound, which currently is the first-choice imaging technique for evaluating nail conditions. A correlation of state-of-the-art clinical and imaging figures supports the review of this topic.

Ultrasound, magnetic resonance imaging and radiography of the finger joints in psoriatic arthritis patients

OBJECTIVE

To report the discrepancies and agreements between ultrasound (US), magnetic resonance imaging (MRI) and radiography of the hand in psoriatic arthritis (PsA), and to compare the sensitivity and specificity of US and radiography to MRI as the gold standard imaging study in PsA.

METHODS

All of the 100 prospectively recruited consecutive PsA patients underwent clinical assessment and concomitant radiographic, US and MRI studies of the metacarpophalangeal, proximal interphalangeal and distal interphalangeal joints of one hand. Synovitis, flexor tenosynovitis, extensor paratenonitis, erosions and bone proliferations were identified and scored. All readers were blinded to clinical data, and agreement was calculated based on prevalence-adjusted bias-adjusted kappa (PABAK).

RESULTS

The prevalence of synovitis, flexor tenosynovitis, extensor paratenonitis and erosions was similar for US and MRI, while that of bone proliferation was significantly increased in US and radiography compared to MRI (P < 0.001). The absolute agreement between US and MRI was good-to-very good for synovitis (85%-96%, PABAK=0.70-0.92), flexor tenosynovitis (93%-98%, PABAK=0.87-0.96), and extensor paratenonitis (95%-98%, PABAK=0.90-0.97). Agreement between US, MRI and radiography was 96%-98% (PABAK=0.92-0.97) for erosions and 71%-93% (PABAK=0.47-0.87) for bone proliferations. Sensitivity of US with MRI as gold standard was higher for synovitis (0.5-0.86) and extensor paratenonitis (0.63-0.85) than for flexor tenosynovitis (0.1-0.75), while the specificity was high for each pathology (0.89-0.98).

CONCLUSION

There is very good agreement between US and MRI for the detection of inflammatory changes in finger joints in PsA. US, radiography and MRI have a good-to-very good agreement for destructive changes.

Introduction of a Simplified Psoriatic Arthritis Magnetic Resonance Imaging Score (sPsAMRIS): A Potential Tool for Treatment Monitoring in Peripheral Psoriatic Arthritis

Background: To evaluate whether a simplified (s) version of the psoriatic arthritis magnetic resonance imaging score (PsAMRIS), sPsAMRIS, is a potential tool for therapy monitoring in psoriatic arthritis (PsA). Methods: Seventeen patients with active psoriatic arthritis (PsA) underwent magnetic resonance imaging (MRI) at 3 T of the clinically dominant hand at baseline and after 6 months. Scoring was performed by two musculoskeletal radiologists in terms of the PsAMRIS and sPsAMRIS, which is a simplified version with reduced item numbers based on prior evaluation of responsiveness to change by standardized response means (SRMs). Both scores were compared by calculation of overall and each sub-score’s SRMs and relative efficacy (RE) after bootstrapping. Results: PsAMRIS sub-scores of MCP joints 3 and 4, and proximal interphalangeal (PIP) joint 4 had the highest SRM (−0.07 each), indicating highest responsiveness to change, and were, therefore, included in sPsAMRIS. Compared to PsAMRIS, sPsAMRIS was characterized by higher SRMs (sPsAMRIS: −0.13 vs. PsAMRIS: −0.02) and higher RE (29.46). sPsAMRIS and PsAMRIS were highly correlated at baseline (r = 0.75, p < 0.01 (Pearson’s correlation)) and at 6-month follow-up (r = 0.64, p = 0.01). Mean time burden for completion of scoring per MRI study was significantly reduced when using PsAMRIS (469 ± 87.03 s) as compared to sPsAMRIS (140.1 ± 21.25 s) (p < 0.001). Conclusion: Due to its similar responsiveness to change compared to standard PsAMRIS, and time efficiency, sPsAMRIS might be a potential diagnostic tool to quantitatively assess and monitor therapy in PsA.

Evaluating Inflammatory Versus Mechanical Back Pain in Individuals with Psoriatic Arthritis: A Review of the Literature

Psoriatic arthritis (PsA) is a chronic immune-mediated disease characterized by psoriatic skin and nail changes, peripheral joint inflammation, enthesitis, dactylitis, and/or axial involvement, either alone or in combination with each other. The presence of axial involvement has been shown to be a marker of PsA severity; however, there is no widely accepted definition of axial involvement in PsA (axPsA) or consensus on how or when to screen and treat patients with suspected axPsA. Chronic back pain is a prominent feature of axPsA and is thought to have a relevant role in early identification of disease. Chronic back pain can be caused by inflammatory back pain (IBP) or mechanical back pain (MBP). However, MBP can complicate recognition of IBP and delay diagnosis of axPsA. While MBP can also be associated with chronic back pain of ≥ 3 months in duration that is typical of IBP, IBP is characterized by inflammation of the sacroiliac joint and lower spine that is differentiated from MBP by key characteristic features, including insidious onset at age < 40 years, improvement with exercise but not with rest, and nighttime pain. This review discusses the differences in identification and management of IBP and MBP in patients with PsA with axPsA. The summary of available evidence highlights the importance of appropriate and timely screening, difficulties and limitations of differential diagnoses and treatment, and unmet needs in axPsA.

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.

[Imaging of psoriatic arthritis and aspects of radiographic progression]

Psoriatic arthritis (PsA) is a heterogeneous multifactorial disease with musculoskeletal involvement, which can be manifested as monoarthritis, oligoarthritis or polyarthritis and in some patients can also affect the axial skeleton. The most frequent indications of inflammation are bone marrow edema and enthesitis. The early and differential diagnosis of PsA is a clinical challenge, particularly as a differential diagnosis from other inflammatory or degenerative diseases of joints. Inflammatory joint and tendon alterations in the region of the extremities and the spine can be visualized with high sensitivity by the use of magnetic resonance imaging (MRI), musculoskeletal sonography (US) and fluorescence optical imaging (FOI). The use of MRI has a prognostic value with respect to the further radiographic course of the disease, particularly in the initial stages of the disease. Structural damage can be specifically and also partially demonstrated 3‑dimensionally in peripheral joints and the spine by the use of computed tomography (CT) and conventional X‑ray imaging. High-resolution peripheral quantitative CT (HR-pQCT) in particular, can visualize pathophysiological processes and the morphological consequences even in early stages of the disease. The values of conventional X‑ray diagnostics, CT, MRI, musculoskeletal US and alternative imaging procedures are presented with respect to the diagnostics and prognosis of the progression of patients with PsA.

Ultrasound assessment in psoriatic arthritis (PsA) and psoriasis vulgaris (non-PsA): which sites are most commonly involved and what features are more important in PsA?

Background

The aim of this study was to find out the most commonly involved sites and the most important ultrasonic features in psoriatic arthritis (PsA).

Methods

In total, 120 PsA patients and 320 psoriasis vulgaris (non-PsA) patients were assessed by grayscale and power Doppler (PD) ultrasound (US). Joints, tendons, enthesis, and bursa changes were observed. Weights of affected anatomical sites of PsA patients (overall weights >90%) were calculated. Affected anatomical sites between PsA and non-PsA patients were compared. Ultrasonic features of joint, tendon, entheses, and bursa changes between PsA and non-PsA patients were also compared. Finally, the test performance of ultrasonic features for the diagnosis of PsA was calculated.

Results

The anatomical sites with the highest weights were the Achilles tendon, quadriceps tendon, and knee; weights of these anatomical sites were all more than 5%. Among the affected anatomical sites of PsA patients, most of the anatomical sites were more greatly affected in the PsA patients than in the non-PsA patients (all P<0.05). The comparison of the affected Achilles tendon, quadriceps tendon, MTP1, subacromial-subdeltoid bursa, MCP4, and MCP3 showed no significance between PsA and non-PsA patients (all P>0.05). Joint synovial thickening, joint PD signal grades, joint bone erosions, tendon sheath synovial thickening, tendon sheath PD signals, enthesis bone erosions, and enthesis PD signals in PsA patients were higher than in non-PsA patients (all P<0.05). Joint PD signal grades, joint bone erosions, enthesis bone erosions, and enthesis PD signals showed the highest specificities, which were 96.06%, 95.15%, 96.93%, and 94.63% respectively.

Conclusions

The most common involvement sites of PsA were the Achilles tendon, quadriceps tendon, and knee, and some sites in non-PsA patients were also highly involved. The most important features in PsA included joint PD signal grades, joint bone erosion, entheses bone erosions, and entheses PD signals in US assessment.

Definition of Remission and Disease Activity Assessment in Psoriatic Arthritis: Evidence and Expert-Based Recommendations

OBJECTIVE

We aimed to reach a consensus on the best instruments to monitor disease activity in patients with psoriatic arthritis (PsA) and to develop a consensus definition of remission.

METHODS

A modified Delphi approach was used. A scientific committee provided statements addressing the definition of remission and the monitoring of PsA in clinical practice. The questionnaire was evaluated in 2 rounds by rheumatologists with experience in managing PsA patients.

RESULTS

A panel of 77 rheumatologists reached agreement on 62 out of the 86 proposed items (72.0%). The most recommended index for monitoring disease activity was DAPSA (cut-off values: ≤4 for remission and >4-14 for low disease activity ([LDA]), MDA (at least 5/7 criteria). In cases with axial involvement, ASDAS was the preferred index (cut-off values: <1.3 for remission and <2.1 for LDA). BASDAI (cut-off values: ≤2 for remission and ≤4 for LDA) may be used as an alternative. PsAID was the preferred tool to assess disease impact.

CONCLUSION

We propose a definition of remission in PsA as the absence of disease activity evaluated by DAPSA or MDA (ASDAS and/or BASDAI in patients with axial involvement), which would imply absence of signs or symptoms of inflammation, physical well-being, lack of disease impact, and absence of inflammation as measured by biological markers.

Psoriatic arthritis for dermatologists

Psoriatic arthritis (PsA) affects up to one-third of patients with psoriasis. It is the major comorbidity of psoriasis because of the likelihood that loss of function and permanent disability will develop if initiation of treatment is delayed. Dermatologists are uniquely positioned to recognize early signs of PsA and be the first-line healthcare practitioners to detect PsA in patients with psoriasis. PsA can affect six clinical domains: peripheral arthritis, dactylitis, enthesitis, psoriasis, psoriatic nail disease, and axial disease. However, not every patient will have involvement of all domains and the domains affected can change over time. Complicating the diagnosis is the condition's similarity with other arthritic diseases and potential heterogeneity. In this article, we provide practical guidance for dermatologists for detecting PsA in patients with psoriasis. We also review the available treatment options by each clinical domain of PsA and give advice on how to interpret the results of PsA clinical trials. Through early recognition of PsA in patients with psoriasis and initiation of proper treatment, dermatologists can help to prevent PsA disease progression, irreversible joint damage, and resultant permanent disability, and improve quality of life.

Genetic signature to provide robust risk assessment of psoriatic arthritis development in psoriasis patients

Psoriatic arthritis (PsA) is a complex chronic musculoskeletal condition that occurs in ~30% of psoriasis patients. Currently, no systematic strategy is available that utilizes the differences in genetic architecture between PsA and cutaneous-only psoriasis (PsC) to assess PsA risk before symptoms appear. Here, we introduce a computational pipeline for predicting PsA among psoriasis patients using data from six cohorts with >7000 genotyped PsA and PsC patients. We identify 9 new loci for psoriasis or its subtypes and achieve 0.82 area under the receiver operator curve in distinguishing PsA vs. PsC when using 200 genetic markers. Among the top 5% of our PsA prediction we achieve >90% precision with 100% specificity and 16% recall for predicting PsA among psoriatic patients, using conditional inference forest or shrinkage discriminant analysis. Combining statistical and machine-learning techniques, we show that the underlying genetic differences between psoriasis subtypes can be used for individualized subtype risk assessment.

Remission in psoriatic arthritis-where are we now?

Advances in treatments and treatment strategies for PsA have led to many patients responding well to management of their disease, and targeting remission as a treatment goal is now a possibility. Treat to target is a strategy aimed at maximizing benefit, irrespective of the type of medication used, by monitoring disease activity and using it to guide therapy. The measurement of response to treatment has been the subject of wide discussions among experts for some time, and many instruments exist. Comparisons of the different measures and their different strengths and weaknesses is ongoing. The impact of modern imaging techniques on monitoring disease progression is also evolving, and advanced techniques using both MRI and US have the potential to improve management of PsA through identification of risk factors for poor prognosis as well as accurate assessment of inflammation and damage, including subclinical disease. Increased understanding of the pathways that drive the pathogenesis of PsA will be key to identifying specific biomarkers for the disease and developing effective treatment strategies. Targets for response, considerations for use of a treat to target strategy in PsA, different imaging techniques and serological aspects of remission are all discussed in this review, and areas for further research are identified.

Power Doppler Ultrasound Evaluation of Peripheral Joint, Entheses, Tendon, and Bursa Abnormalities in Psoriatic Patients: A Clinical Study

OBJECTIVE

To evaluate the prevalence rates of peripheral joint, enthesis, tendon, and bursa abnormalities by power Doppler (PD) ultrasonic examination in patients with psoriatic arthritis (PsA), psoriatic patients without clinical signs of arthritis (non-PsA psoriasis group), and healthy individuals, to detect subclinical PsA.

METHODS

A total of 253 healthy volunteers, 242 non-PsA psoriatic patients, and 86 patients with PsA were assessed by 2-dimensional and power Doppler (PD) ultrasound. Peripheral joint, enthesis, tendon, and bursa abnormalities were observed, characterizing abnormal PD. The affected patients and sites with abnormalities in various ages were compared among groups; PD signal grades for the abnormalities were also compared.

RESULTS

In the PsA group, significantly higher percentages of sites showing joint effusion/synovitis, enthesitis, and tenosynovitis in all age groups, and markedly higher rates of sites with bursitis were found in young and middle age groups, compared with the non-PsA and control groups (all p < 0.01). Meanwhile, the non-PsA group showed significantly higher rates of joint effusion/synovitis and enthesitis sites, and elevated PD signal grades of synovitis, enthesitis, and tenosynovitis in comparison with the control group, both in young and middle age groups (all p < 0.01).

CONCLUSION

Patients with PsA have high percentages and PD signal grades of peripheral joint, tendon, enthesis, and bursa involvement. Young and middle-aged non-PsA patients have high synovitis and enthesitis percentages, and elevated PD signal grades of synovitis, enthesitis, and tenosynovitis.

Sonography of Non-neoplastic Disorders of the Hand and Wrist Tendons

Tendon disorders commonly cause hand and wrist disability and curtail the performance of work-related duties or routine tasks. Imaging is often needed for diagnosis, but it requires knowledge of the complex anatomic structures of the tendons of the hand and wrist as well as familiarity with related disorders. This review article aims to provide medical professionals with guidelines for the sonographic assessment of the tendons of hand and wrist and related disorders. Sonographic features of tendon disorders affecting the hand and wrist are described here, specifically: infectious tenosynovitis; tendon rupture or tearing; stenosing forms of tenosynovitis such as De Quervain disease and trigger finger; intersection syndrome; insertional tendinopathy; several forms of tendinous instability such as extensor carpi ulnaris instability, climber finger, and boxer knuckle; and tendinopathy in inflammatory rheumatic diseases. Postsurgical evaluation of the hand and wrist tendons is also discussed, including the healthy and pathologic appearances of operated tendons as well as impingement from orthopedic hardware. In conclusion, sonography is effective in assessing the tendons of the hand and wrist and related disorders and represents a valuable tool for diagnosis.

What the Rheumatologist Is Looking for and What the Radiologist Should Know in Imaging for Rheumatoid Arthritis

This article outlines what the rheumatologist is looking for and wants to know in the clinical diagnosis and imaging of rheumatoid arthritis, and what the radiologist should know to facilitate this.

Ultrasound in Arthritis

Ultrasound is currently performed in everyday rheumatologic practice. It is used for early diagnosis, to monitor treatment results, and to diagnose remission. The spectrum of pathologies seen in arthritis with ultrasound includes early inflammatory features and associated complications. This article discusses the spectrum of ultrasound features of arthritides seen in rheumatoid arthritis and other connective tissue diseases in adults, such as Sjögren syndrome, lupus erythematosus, dermatomyositis, polymyositis, and juvenile idiopathic arthritis. Ultrasound findings in spondyloarthritis, osteoarthritis, and crystal-induced diseases are presented. Ultrasound-guided interventions in patients with arthritis are listed, and the advantages and disadvantages of ultrasound are discussed.

Treating Psoriasis and Psoriatic Arthritis: Position Paper on Applying the Treat-to-target Concept to Canadian Daily Practice

Objective.

To develop preliminary treat-to-target (T2T) recommendations for psoriasis and psoriatic arthritis (PsA) for Canadian daily practice.

Methods.

A task force composed of expert Canadian dermatologists and rheumatologists performed a needs assessment among Canadian clinicians treating these diseases as well as an extensive literature search on the outcome measures used in clinical trials and practice.

Results.

Based on results from the needs assessment and literature search, the task force established 5 overarching principles and developed 8 preliminary T2T recommendations.

Conclusion.

The proposed recommendations should improve management of psoriasis and PsA in Canadian daily practice. However, these recommendations must be further validated in a real-world observational study to ensure that their use leads to better longterm outcomes.

Selected issues in diagnostic imaging of spondyloarthritides: psoriatic arthritis and juvenile spondyloarthritis

Spondyloarthritides (also known as spondyloarthropathies) are a group of rheumatic diseases that consists of diversified entities, i.e. ankylosing spondylitis, reactive arthritis, psoriatic arthritis, arthritis in the course of Crohn's disease and ulcerative colitis, and juvenile spondyloarthropathies. In the diagnostics of spondyloarthritides, plain radiography has played a crucial role for years due to its undisputed ability to show distinctive bony changes. Yet as those diseases often manifest themselves by soft tissue pathology and bone marrow inflammation, ultrasonography and magnetic resonance imaging are currently a subject of numerous studies in the quest for setting up diagnostic criteria, especially at early stages of inflammatory processes. In our review, we present an up-to-date insight into classifications, etiopathogenesis and imaging of psoriatic arthritis and juvenile spondyloarthritis.

Assessment of enthesitis in patients with psoriatic arthritis using clinical examination and ultrasound

BACKGROUND

Enthesitis is a major feature of psoriatic arthritis. However, clinical assessment of enthesitis is known to lack accuracy and have poor interobserver reliability.

OBJECTIVE

To determine effect of training on clinical assessment of enthesitis and to compare ultrasonography with clinical examination for the detection of entheseal abnormalities.

METHODS

20 rheumatologists performed repeated assessment of enthesitis in patients with established psoriatic arthritis before and after a 2-hour training session in standardised enthesitis count according to Leeds Enthesitis Index (LEI) and Spondyloarthritis Research Consortium of Canada Enthesitis Index (SPARCC). Moreover, 20 patients underwent clinical and ultrasonographic examination of entheses to evaluate consensus-based elementary lesions of enthesitis.

RESULTS

Training significantly increased Intra-class Correlation Coefficient for LEI from 0.18 to 0.82 and for SPARCC from 0.38 to 0.67. Ultrasound examination showed high associations between hypoechogenicity and increased thickness of the entheses and clinical examination. There was no correlation between erosions and enthesophytes found by ultrasound and clinical assessments.

CONCLUSION

Training in standardised enthesitis scoring systems significantly improved clinical assessments of enthesitis and should be performed before use in daily clinical practice. Ultrasound revealed more advanced stages of enthesitis, such as enthesophytes and erosions, which were not detected with clinical examination.

Cross-sectional imaging of adult crystal and inflammatory arthropathies

This article highlights the key aspects and current perspectives of the role of cross-sectional imaging in adult crystal and inflammatory arthropathies in adults, briefly discussing CT, and particularly focusing on MRI and US imaging as it supplements the conventional radiography. The role of conventional and advanced MR imaging techniques and imaging findings in this domain is discussed and illustrated with case examples. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. This article contains images and data, which were collected from patients as a part of a retrospective IRB from the institutional teaching files and informed consent was waived.

Diagnostic imaging of psoriatic arthritis. Part II: magnetic resonance imaging and ultrasonography

Plain radiography reveals specific, yet late changes of advanced psoriatic arthritis. Early inflammatory changes are seen both on magnetic resonance imaging and ultrasound within peripheral joints (arthritis, synovitis), tendons sheaths (tenosynovitis, tendovaginitis) and entheses (enthesitis, enthesopathy). In addition, magnetic resonance imaging enables the assessment of inflammatory features in the sacroiliac joints (sacroiliitis), and the spine (spondylitis). In this article, we review current opinions on the diagnostics of some selective, and distinctive features of psoriatic arthritis concerning magnetic resonance imaging and ultrasound and present some hypotheses on psoriatic arthritis etiopathogenesis, which have been studied with the use of magnetic resonance imaging. The following elements of the psoriatic arthritis are discussed: enthesitis, extracapsular inflammation, dactylitis, distal interphalangeal joint and nail disease, and the ability of magnetic resonance imaging to differentiate undifferentiated arthritis, the value of whole-body magnetic resonance imaging and dynamic contrast-enhanced magnetic resonance imaging.

Diagnostic imaging of psoriatic arthritis. Part I: etiopathogenesis, classifications and radiographic features

Psoriatic arthritis is one of the spondyloarthritis. It is a disease of clinical heterogenicity, which may affect peripheral joints, as well as axial spine, with presence of inflammatory lesions in soft tissue, in a form of dactylitis and enthesopathy. Plain radiography remains the basic imaging modality for PsA diagnosis, although early inflammatory changes affecting soft tissue and bone marrow cannot be detected with its use, or the image is indistinctive. Typical radiographic features of PsA occur in an advanced disease, mainly within the synovial joints, but also in fibrocartilaginous joints, such as sacroiliac joints, and additionally in entheses of tendons and ligaments. Moll and Wright classified PsA into 5 subtypes: asymmetric oligoarthritis, symmetric polyarthritis, arthritis mutilans, distal interphalangeal arthritis of the hands and feet and spinal column involvement. In this part of the paper we discuss radiographic features of the disease. The next one will address magnetic resonance imaging and ultrasonography.

Ultrasound and magnetic resonance imaging assessment of joint disease in symptomatic patients with cystic fibrosis arthropathy

OBJECTIVES

Cystic fibrosis arthropathy (CFA) is a term commonly used for joint pain with and without swelling seen in some patients with CF. Early studies into CFA focused on the presence of rheumatoid factor and immunological changes on synovial biopsy, with parallels drawn between respiratory and joint activity. Identification of anti-cyclic citrullinated peptide antibodies (anti-CCP) as a marker of rheumatoid arthritis (RA), along with increased access to sensitive imaging techniques including ultrasound (US) and magnetic resonance imaging (MRI), offer great potential to investigate and more accurately understand the type(s) of inflammatory arthritis that may underlie CFA. The aim of this study was to phenotype an active CFA cohort using serology and imaging, as a basis for further work in this understudied area.

METHODS

This was a prospective observational cohort study of symptomatic CFA patients presenting with joint pain. Participants underwent serological testing, clinical and US joint and entheseal assessment, as well as MRI of the most symptomatic joint/joint area.

RESULTS

Ten symptomatic patients were studied with 9/10 having positive clinical findings. Inflammatory changes on US were seen in 8/10 cases. Five patients had positive findings on MRI (3 of whom had received IV gadolinium contrast). This included patients with significant erosive changes. One patient was anti-CCP positive suggestive of RA, and two were anti-nuclear antibody positive.

CONCLUSION

Imaging, and to a lesser extent serology, identified inflammatory joint pathology in a proportion of cases, providing important data to explore in a large CFA cohort examining the clinical and imaging phenotype of this group.

Safety and efficacy of intra-articular anti-tumor necrosis factor α agents compared to corticosteroids in a treat-to-target strategy in patients with inflammatory arthritis and monoarthritis flare

The aim of this study was to assess safety and efficacy of ultrasonography (US)-guided intra-articular injections using tumor necrosis factor (TNF) blockers compared to corticosteroids in rheumatoid arthritis (RA) or psoriatic arthritis (PsA) patients, experiencing refractory monoarthritis despite the current systemic therapy. Eighty-two patients were randomized to receive three intra-articular injections monthly of either corticosteroid or TNF blockers. Primary endpoints were the safety and an improvement greater than 20% for visual analogic scales of involved joint pain in patients injected with anti-TNFα. Further clinical, US, and magnetic resonance imaging (MRI) evaluations were considered secondary endpoints. Intra-articular TNF blockers are a safe strategy, determining a significant reduction of patient and physician reported clinical outcomes and US/MRI scores, in RA and PsA patients, when compared to intra-articular injections of corticosteroids. US guidance excluded the possibility to inject the drug in the wrong site, maximizing local effects, reducing systemic effects, and increasing the safety of the procedure. Patients with inflammatory monoarthritis could be successfully treated with US-guided intra-articular TNF blockers that are a safe and well tolerated procedure, to achieve a longstanding clinical and radiological good clinical response and/or disease remission.

Proceedings from The 8th Annual International Society for Musculoskeletal Imaging in Rheumatology (ISEMIR) Conference

The International Society for Musculoskeletal Imaging in Rheumatology (ISEMIR) was founded in 2005 with the goal of discussing matters related to imaging in rheumatology, particularly, validation, education, and use in both clinical practice and research. The field of musculoskeletal (MSK) imaging is continuously evolving; therefore, education for healthcare providers in this field is of paramount importance. ISEMIR's international faculty and world-renowned experts presented the newest information as it relates to the use of magnetic resonance imaging (MRI) and ultrasound (US) at the 8th annual ISEMIR meeting that took place on April 17-18 in Santa Monica, California. Presentations from the meeting can be viewed at www.isemir.org.

The Epidemiology of Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic systemic inflammatory disorder characterized by joint and entheseal inflammation with a prevalence of 0.05% to 0.25% of the population and 6% to 41% of patients with psoriasis. PsA is a highly heterogeneous inflammatory arthritis. In this review, current knowledge is discussed regarding the epidemiology of PsA, including disease manifestations, classification criteria for adult and juvenile PsA, methods for recognizing early PsA, including use of screening tools and knowledge of risk factors for PsA, and medical comorbidities associated with PsA.