Psoriatic arthritis and rheumatoid arthritis: findings in contrast-enhanced MRI

Pathophysiology, diagnosis, and herbal medicine-based therapeutic implication of rheumatoid arthritis: an overview

Rheumatoid arthritis (RA) stands as an autoimmune disorder characterized by chronic joint inflammation, resulting in profound physiological alterations within the body. Affecting approximately 0.4-1.3% of the global population, this condition poses significant challenges as current therapeutic approaches primarily offer symptomatic relief, with the prospect of complete recovery remaining elusive. This review delves into the contemporary advancements in understanding the pathophysiology, diagnosis, and the therapeutic potential of herbal medicine in managing RA. Notably, early diagnosis during the initial stages emerges as the pivotal determinant for successful recovery post-treatment. Utilizing tools such as Magnetic Resonance Imaging (MRI), anti-citrullinated peptide antibody markers, and radiography proves crucial in pinpointing the diagnosis of RA with precision. Unveiling the intricate pathophysiological mechanisms of RA has paved the way for innovative therapeutic interventions, incorporating plant extracts and isolated phytoconstituents. In the realm of pharmacological therapy for RA, specific disease-modifying antirheumatic drugs have showcased commendable efficacy. However, this conventional approach is not without its drawbacks, as it is often associated with various side effects. The integration of methodological strategies, encompassing both pharmacological and plant-based herbal therapies, presents a promising avenue for achieving substantive recovery. This integrated approach not only addresses the symptoms but also strives to tackle the underlying causes of RA, fostering a more comprehensive and sustainable path towards healing.

Disease characteristics, pathogenesis, and treatment controversies of axial psoriatic arthritis

Axial psoriatic arthritis (axPsA) has considerable overlap with axial spondyloarthritis (axSpA) but has some unique features that sometimes preclude classification into axSpA. It has some clinical and radiographic differences compared to axSpA. Imaging typically shows asymmetric syndesmophytes, mainly in the cervical spine, with less frequent sacroiliitis. It more commonly presents later in life and is associated with less severe inflammatory back pain than axSpA. The interleukin (IL) IL-23/IL-17 axis is central to the pathogenesis of both diseases. However, the response to therapies targeting these cytokines has been different. IL-23 inhibitors are ineffective in axSpA but may be effective in psoriatic arthritis (PsA). Recent post hoc analyses of clinical trial data with IL-23 inhibitors in PsA have raised the possibility of their efficacy in axPsA and need evaluation in future clinical trials. Moreover, there is a need for classification criteria for axPsA and better tools to assess therapeutic response.

Imaging in inflammatory arthritis: progress towards precision medicine

Imaging techniques such as ultrasonography and MRI have gained ground in the diagnosis and management of inflammatory arthritis, as these imaging modalities allow a sensitive assessment of musculoskeletal inflammation and damage. However, these techniques cannot discriminate between disease subsets and are currently unable to deliver an accurate prediction of disease progression and therapeutic response in individual patients. This major shortcoming of today's technology hinders a targeted and personalized patient management approach. Technological advances in the areas of high-resolution imaging (for example, high-resolution peripheral quantitative computed tomography and ultra-high field MRI), functional and molecular-based imaging (such as chemical exchange saturation transfer MRI, positron emission tomography, fluorescence optical imaging, optoacoustic imaging and contrast-enhanced ultrasonography) and artificial intelligence-based data analysis could help to tackle these challenges. These new imaging approaches offer detailed anatomical delineation and an in vivo and non-invasive evaluation of the immunometabolic status of inflammatory reactions, thereby facilitating an in-depth characterization of inflammation. By means of these developments, the aim of earlier diagnosis, enhanced monitoring and, ultimately, a personalized treatment strategy looms closer.

Anatomically Accurate, High-Resolution Modeling of the Human Index Finger Using In Vivo Magnetic Resonance Imaging

Anatomically accurate models of a human finger can be useful in simulating various disorders. In order to have potential clinical value, such models need to include a large number of tissue types, identified by an experienced professional, and should be versatile enough to be readily tailored to specific pathologies. Magnetic resonance images were acquired at ultrahigh magnetic field (7 T) with a radio-frequency coil specially designed for finger imaging. Segmentation was carried out under the supervision of an experienced radiologist to accurately capture various tissue types (TTs). The final segmented model of the human index finger had a spatial resolution of 0.2 mm and included 6,809,600 voxels. In total, 15 TTs were identified: subcutis, Pacinian corpuscle, nerve, vein, artery, tendon, collateral ligament, volar plate, pulley A4, bone, cartilage, synovial cavity, joint capsule, epidermis and dermis. The model was applied to the conditions of arthritic joint, ruptured tendon and variations in the geometry of a finger. High-resolution magnetic resonance images along with careful segmentation proved useful in the construction of an anatomically accurate model of the human index finger. An example illustrating the utility of the model in biomedical applications is shown. As the model includes a number of tissue types, it may present a solid foundation for future simulations of various musculoskeletal disease processes in human joints.

Comparison of the axillary lymph node between rheumatoid arthritis and psoriatic arthritis with computed tomography

Backgrounds

There is a lack of universally available biomarker to differentiate rheumatoid arthritis (RA) and psoriatic arthritis (PsA).

Purpose

to see if the size of the axillary lymphnodes (ALNs) and the frequency of lymphadenopathy are useful biomarker to differentiate RA and PsA.

Material and Methods

Forty RA and 19 PsA patients without previous biologics usage were retrospectively included. Chest CT was assessed for the presence of lymphadenopathy and the size of the largest ALN. Frequency of lymphadenopathies was statistically compared between RA and PsA. The short axis and the long axis of the largest ALN were also compared and receiver operating characteristic (ROC) curve analysis was performed.

Results

Frequency of axillary lymphadenopathy was significantly higher in RA than in PsA (80% vs 31.6%, p < .001). Number of lymphadenopathies in each patient was also significantly higher in RA than in PsA (3.0 vs 1.2 per patient, p = .005). Sensitivity and specificity for differentiating RA from PsA by the presence of at least one axillary lymphadenopathy were 0.8 and 0.68, respectively. The short axis of the largest ALNs in RA was significantly longer than in PsA (6.5 ± 1.6 mm vs 4.7 ± 1.7 mm, p < .001). ROC curve analysis of the short axis showed AUC of 0.75 ( p = .002) and the cutoff value of 5.1 mm with a sensitivity of 0.83 and specificity of 0.74, when differentiating RA and PsA.

Conclusion

Presence of ALN lymphadenopathy and the short axis of the largest ALN may have a potential utility in differentiating RA and PsA.

A Systematic Approach to Diagnosing Arthritis Based on Radiological Imaging

:

Radiology plays key roles in diagnosis of arthritis. We herein suggest an algorithmic approach to diagnosing arthritis. First, the number of joint involvements is reviewed. Monoarticular arthritis includes septic arthritis, pigmented villonodular synovitis, and synovial chondromatosis. Second, polyarticular arthritis can be categorized by its characteristics: erosive, productive and mixed. Erosive disease includes rheumatoid arthritis, hemophilia, and amyloidosis while productive disease includes osteoarthritis, and hemochromatosis. Third, mixed diseases are subcategorized by symmetricity. Ankylosing spondylitis and inflammatory bowel disease related arthritis affect joints symmetrically while psoriatic arthritis, reactive arthritis, and crystalline arthropathy are asymmetric. Adjacent soft tissue density, periostitis, and bone density are ancillary findings that can be used as additional differential diagnostic clues. The final step in identifying the type of arthritis is to check whether the location is a site frequently affected by one particular disease over another. This systematic approach would be helpful for radiologist to diagnose arthritis.

Comparison of Clinical Manifestations in Rheumatoid Arthritis vs. Spondyloarthritis: A Systematic Literature Review

INTRODUCTION

Misclassification of spondyloarthritis (SpA) as rheumatoid arthritis (RA) may lead to delayed SpA diagnosis and suboptimal therapeutic outcomes. Here, we evaluate the literature on clinical manifestations in patients with SpA and RA, particularly seronegative RA, to understand the potential overlap, distinctions, and most reliable approaches to accurate diagnosis.

METHODS

In this systematic literature review, conducted according to PRISMA guidelines, we searched key biomedical databases for English-language publications of original research articles (up to July 23, 2020) and rheumatology conference abstracts (January 1, 2018-July 31, 2020) reporting key SpA clinical presentations in patients with SpA or RA. Publications were assessed for eligibility by two independent reviewers; discrepancies were resolved by a third. Studies were evaluated for publication quality using the Downs and Black checklist.

RESULTS

Of 4712 records retrieved, 79 met the inclusion criteria and were included in the analysis. Of these, 54 included study populations with SpA and RA, and 25 with seropositive and/or seronegative RA. Entheseal abnormalities were more frequently reported among patients with SpA than RA and with seronegative vs. seropositive RA. Psoriasis, nail psoriasis, and dactylitis were exclusively seen in SpA vs. RA. In most publications (70 of 79), advanced imaging techniques allowed for more accurate distinction between SpA and RA. Overlapping clinical characteristics occur in SpA and RA, including inflammation and destruction of joints, pain, diminished functional ability, and increased risk for comorbidities. However, of 54 studies comparing SpA and RA populations, only seven concluded that no distinction can be made based on the SpA manifestations and outcomes examined.

CONCLUSIONS

Typical SpA-related clinical symptoms and signs were observed in patients with RA, suggesting that misclassification could occur. Availability of advanced imaging modalities may allow for more prompt and comprehensive evaluation of peripheral manifestations in SpA and RA, reducing misclassification and delayed diagnosis.

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.

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.

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.

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.

Differentiating Rheumatoid and Psoriatic Arthritis of the Hand: Multimodality Imaging Characteristics

Accurate diagnosis and therapeutic intervention at an early stage is paramount for the management of rheumatoid arthritis (RA) and psoriatic arthritis (PsA), which are the two major types of inflammatory arthritis that involve the hand joints. As more disease-specific medications are developed, medication selection according to the correct diagnosis becomes more important. A delay in diagnosis and inappropriate medication selection may result in poor functional prognosis. However, clinical differentiation between RA and PsA can be challenging and may become largely dependent on imaging interpretation results. Although there is substantial overlap in the imaging findings of RA and PsA, there are differences in the affected primary target sites, reflected by the various patterns of joint involvement, and different microanatomic localization of abnormalities within a single joint in each disease. Therefore, appropriate use of various imaging modalities and accurate image interpretation add significant value to the diagnosis and treatment process. The synovio-entheseal complex is an important concept for understanding the imaging features of PsA. The authors review the different features of RA and PsA of the hands seen with various imaging modalities, including radiography, US, MRI, and dual-energy CT, with updates on the contemporary role of imaging in diagnosis and treatment. The radiologist should have sufficient knowledge to interpret imaging findings and understand the strengths and weaknesses of each modality to recommend the appropriate imaging method and differentiate both diseases accurately. ^©RSNA, 2020.

A Comparative Study of High-Resolution Chemical-Shift-Eliminated Magnetic Resonance Imaging of Finger Specimens with Microcomputed Tomography

Objective:

High-resolution images of finger joints with chemical-shift elimination can be obtained using an interleaved water-fat (IWF) sequence. This study assessed IWF imaging of finger joints in the delineation of bone structures by comparing images of cadaver fingers with those of microcomputed tomography (CT) that served as a standard reference.

Materials and Methods:

IWF images with spatial resolution of 176 µ × 176 µ × 300 µ were obtained from the distal and proximal interphalangeal joints of two cadaver finger specimens using a custom-built radiofrequency receive coil at 1.5T. Regular three-dimensional gradient-echo (GRE) images were also acquired with similar parameters and compared with the IWF images to evaluate the effects of chemical shift. Micro-CT scans were obtained and served as the standard reference. The image data were reviewed by two experienced musculoskeletal radiologists in consensus. The delineation of normal joint structures and abnormalities in the finger specimens as revealed by the magnetic resonance imaging (MRI) and micro-CT images were compared. The IWF and regular GRE images were assigned scores 0–3 for the depiction of apparent marginal bone defects, with zero being the same in appearance to the micro-CT image and three as having minimal resemblance to it. Statistical analysis of the scoring results was conducted to compare the two MRI techniques.

Results:

The high-resolution IWF images provided accurate delineation of bone and calcified structures as seen in micro-CT. The thickness of subchondral bone was depicted similarly on the IWF water + fat and the micro-CT images but not on the regular GRE images. The regular GRE sequence showed false marginal bone defects not observed with IWF and micro-CT. In addition, the IWF water-only images facilitated the identification of bone cyst by revealing its water content.

Conclusion:

High-resolution IWF imaging should be useful for the early diagnosis and treatment assessment of arthritis and should also benefit basic research in the pathophysiology of the disease.

Imaging in rheumatoid arthritis, psoriatic arthritis, axial spondyloarthritis, and osteoarthritis: An international viewpoint on the current knowledge and future research priorities

Imaging is increasingly used in the routine management of rheumatic diseases as well as in the clinical trials of these disorders. This viewpoint, authored by a group of international imaging experts following two meetings dedicated to imaging in rheumatology, reports a consensus about the current knowledge and addresses where further research should be focused based on the views of the international imaging experts and discussion of the evidence with attending imaging practitioners. The goal was to maximize the potential of imaging to improve the clinical management of four rheumatic diseases. These rheumatic diseases include rheumatoid arthritis, psoriatic arthritis, axial spondyloarthritis, and osteoarthritis.

Rheumatoid Arthritis Revisited - Advanced Imaging Review

Rheumatoid Arthritis (RA) is a multisystem disorder, which causes significant morbidity. An early diagnosis of RA is essential to prevent the development of irreversible bone and joint changes. The disease has characteristic clinical features, but an early evaluation of the quantum of disease may be difficult with plain radiography alone. Recent developments in the imaging of RA have contributed significantly to an early diagnosis of the disease. In this article, we review the role and current status of various imaging modalities including recent advances in the evaluation and follow-up of early RA.

Subclinical joint inflammation in patients with psoriasis without concomitant psoriatic arthritis: a cross-sectional and longitudinal analysis

OBJECTIVES

To search for subclinical inflammatory joint disease in patients with psoriasis without psoriatic arthritis (PsA), and to determine whether such changes are associated with the later development of PsA.

METHODS

Eighty-five subjects without arthritis (55 with psoriasis and 30 healthy controls) received high field MRI of the hand. MRI scans were scored for synovitis, osteitis, tenosynovitis and periarticular inflammation according to the PsAMRIS method. Patients with psoriasis additionally received complete clinical investigation, high-resolution peripheral quantitative CT for detecting erosions and enthesiophytes and were followed up for at least 1 year for the development of PsA.

RESULTS

47% of patients with psoriasis showed at least one inflammatory lesion on MRI. Synovitis was the most prevalent inflammatory lesion (38%), while osteitis (11%), tenosynovitis (4%) and periarticular inflammation (4%) were less frequent. The mean (±SD) PsAMRIS synovitis score was 3.0±2.5 units. Enthesiophytes and bone erosions were not different between patients with psoriasis with or without inflammatory MRI changes. The risk for developing PsA was as high as 60% if patients had subclinical synovitis and symptoms related to arthralgia, but only 13% if patients had normal MRIs and did not report arthralgia.

CONCLUSIONS

Prevalence of subclinical inflammatory lesions is high in patients with cutaneous psoriasis. Arthralgia in conjunction with MRI synovitis constitutes a high-risk constellation for the development of PsA.

Advancement in contemporary diagnostic and therapeutic approaches for rheumatoid arthritis

This review is intended to provide a summary of the pathogenesis, diagnosis and therapies for rheumatoid arthritis. Rheumatoid arthritis (RA) is a common form of inflammatory autoimmune disease with unknown aetiology. Bone degradation, cartilage and synovial destruction are three major pathways of RA pathology. Sentinel cells includes dendritic cells, macrophages and mast cells bound with the auto antigens and initiate the inflammation of the joints. Those cells further activates the immune cells on synovial membrane by releasing inflammatory cytokines Interleukin 1, 6, 17, etc., Diagnosis of this disease is a combinational approach comprises radiological imaging, blood and serology markers assessment. The treatment of RA still remain inadequate due to the lack of knowledge in disease development. Non-steroidal anti-inflammatory drugs, disease modifying anti rheumatic drugs and corticosteroid are the commercial drugs to reduce pain, swelling and suppressing several disease factors. Arthroscopy will be an useful method while severe degradation of joint tissues. Gene therapy is a major advancement in RA. Suppressor gene locus of inflammatory mediators and matrix degrading enzymes were inserted into the affected area to reduce the disease progression. To overcome the issues aroused from those therapies like side effects and expenses, phytocompounds have been investigated and certain compounds are proved for their anti-arthritic potential. Furthermore certain complementary alternative therapies like yoga, acupuncture, massage therapy and tai chi have also been proved for their capability in RA treatment.

[Enthesitis in connection with spondyloarthritides]

Enthesitis is a frequent manifestation in spondyloarthritis (SpA) and psoriatic arthritis (PsA) and can be found in up to 40% of patients with SpA. Because of the pathognomonic relevance the classification criteria for SpA and PsA use enthesitis as an entrance or secondary criterion. Enthesitis is most frequently localized at the heel but it can occur at any insertion of an enthesis into the bone. When diagnosing enthesitis differential diagnoses should be considered, mechanical-degenerative causes and fibromyalgia in particular should be excluded. The imaging techniques power Doppler ultrasound (PDUS) and magnetic resonance imaging (MRI) are most helpful in making the diagnosis. The therapeutic options for enthesitis are limited. Nonsteroidal antirheumatic drugs (NSARD) and local injections of corticosteroids are recommended. In small clinical trials no efficacy of disease modifying antirheumatic drugs (DMARD) could be demonstrated. In contrast, tumor necrosis factor alpha (TNF-alpha) blockers were shown to be highly effective in randomized controlled trials for SpA and PsA but they are not currently approved for enthesitis only.

[Enthesitis in the context of spondyloarthritides]

Enthesitis is a frequent manifestation in spondyloarthritis (SpA) and psoriatic arthritis (PsA) and can be found in up to 40 % of patients with SpA. Because of the pathognomonic relevance the classification criteria for SpA and PsA use enthesitis as an entrance or secondary criterion. Enthesitis is most frequently localized at the heel but it can occur at any insertion of an enthesis into the bone. When diagnosing enthesitis differential diagnoses should be considered, mechanical-degenerative causes and fibromyalgia in particular should be excluded. The imaging techniques power Doppler ultrasound (PDUS) and magnetic resonance imaging (MRI) are most helpful in making the diagnosis. The therapeutic options for enthesitis are limited. Nonsteroidal antirheumatic drugs (NSARD) and local injections of corticosteroids are recommended. In small clinical trials no efficacy of disease modifying antirheumatic drugs (DMARD) could be demonstrated. In contrast, tumor necrosis factor alpha (TNF-alpha) blockers were shown to be highly effective in randomized controlled trials for SpA and PsA but they are not currently approved for enthesitis only.

Psoriatic arthritis: Epidemiology, diagnosis, and treatment

Our understanding of psoriatic arthritis has evolved as new knowledge of the disease has emerged. However, the exact prevalence of psoriatic arthritis is unknown, and its pathogenesis has not been fully elucidated. Genetic, environmental, and immunologic factors have all been implicated in disease development. Early diagnosis and treatment have become primary objectives in clinical rheumatology. Psoriatic arthritis not only causes functional impairment, but also increases mortality risk of patients. The advent of new therapeutic agents capable of arresting the progression of joint damage is expected. However, early psoriatic arthritis assessment remains limited. The objectives of this article are to outline the epidemiology, diagnosis, and treatment of psoriatic arthritis and to suggest a paradigm for identifying early psoriatic arthritis patients.

MRI and ultrasonography for diagnosis and monitoring of psoriatic arthritis

Imaging techniques such as magnetic resonance imaging (MRI) and ultrasound (US) have been increasingly used in psoriatic arthritis (PsA) providing additional clues to the pathogenesis of this peripheral, axial and dermatologic disease. This has improved our understanding of the disease and can be used to aid diagnosis and then to follow outcomes of treatment. Both imaging modalities have highlighted the differing involvement of PsA when compared with rheumatoid arthritis (RA) with a significant burden of entheseal disease, flexor tenosynovitis (occurring alone or as part of dactylitis) and other extra-capsular inflammatory changes. MRI scanning has also highlighted the link between the nail and the distal interphalangeal (DIP) joint confirming previous clinical observations. Imaging studies in psoriasis patients have discovered a high level of subclinical inflammatory change but the clinical importance of such findings has not yet been defined. The potential use of MRI and US to monitor treatment outcomes has encouraged research in this field. In MRI, the PsA MRI Score (PsAMRIS) has been developed with promising initial validation. In US, work is ongoing with the OMERACT group to define key pathologies and to develop scoring systems. A few scoring systems are available for enthesitis scoring using US which are further being developed and refined. Further improvements in technologies in both of these fields offer exciting possibilities for future research. New MRI techniques offer the chance to image previously 'dark' structures such as tendons which is key in spondyloarthritides (SpA). Sonoelastography may also improve our understanding of tendon involvement in SpA. Whole-body multi-joint MRI allows a 'snapshot' of inflammation in PsA including joints, entheses and spinal involvement. Three-dimensional US should improve reliability and comparability of US scoring reducing inter-operator variability. The latest machines offer real-time fusion imaging employing US machines with an in-built virtual navigator system linked to previous MRI acquisitions. All of these new techniques should aid our understanding of PsA and our ability to objectively measure response to therapy.

The comparison of efficacy of different imaging techniques (conventional radiography, ultrasonography, magnetic resonance) in assessment of wrist joints and metacarpophalangeal joints in patients with psoriatic arthritis

Background:

Psoriatic arthritis (PsA) is a chronic inflammatory joint disease which develops in patients with psoriasis. The rheumatoid factor is characteristically absent in the serum of PsA patients. Etiology of the disease is still unclear but a number of genetic associations have been identified. Inheritance of the disease is multilevel and the role of environmental factors is emphasized. Immunology of PsA is also quite complex. Inflammation is caused by immunological reactions leading to a release of kinins. Destructive changes in bones usually appear after a few months from the onset of clinical symptoms.

Material/Methods:

PsA typically involves joints of the axial skeleton with an asymmetrical patern. The spectrum of symptoms includes inflammatory changes in attachments of articular capsules, tendons, and ligaments to bone surface. The disease can have a diverse clinical course but usually manifests as oligoarthritis.

Results:

Imaging plays an important role in the diagnosis of PsA. Classical radiography has been used for this purpose for over a hundred years. It allows to identify late stages of the disease, when bone tissue is affected. In the last 20 years however many new imaging modalities, such as ultrasonography (US), computed tomography (CT) and magnetic resonance (MR), have been developed and became important diagnostic tools for evaluating rheumatoid diseases. They enable the assessment and monitoring of early inflammatory changes.

Conclusions:

As a result, patients have earlier access to modern treatment and thus formation of destructive changes in joints can be markedly delayed or even avoided.

Performance of hands and feet radiographs in differentiation of psoriatic arthritis from rheumatoid arthritis

AIM

The purpose of this study was to determine useful radiographic findings for differentiating psoriatic arthritis (PsA) from rheumatoid factor (RF)-positive or -negative rheumatoid arthritis (RA) in Japanese patients.

METHODS

We accrued 85 patients with PsA. Controls included 135 patients with RA (85 RF-positive, 50 RF-negative) matched for gender and disease duration with PsA patients. Radiographs of hands and feet were obtained, and distal interphalangeal (DIP) erosive disease, joint osteolysis, tuft osteolysis, juxta-articular bony proliferation (JBP), periosteal new bone formation and bony ankylosis, which were identified using the definitions developed by an earlier study, were compared between the PsA and RA groups.

RESULTS

For radiographic features of hands, the frequencies of JBP, periosteal new bone, and diffuse soft tissue swelling of the fingers were significantly higher in PsA patients than in RF-positive RA patients. However, only the frequency of JBP significantly differed between PsA and RF-negative RA patients. In feet, the frequencies of DIP erosive disease, tuft osteolysis, JBP, and diffuse soft tissue swelling of the toes were significantly higher in PsA patients than in RF-positive RA patients. However, only the frequency of JBP significantly differed between PsA and RF-negative RA patients.

CONCLUSION

JBP was the most important radiographic feature for discriminating PsA from both RF-positive and -negative RA, confirming the study by the CASPAR group that showed that JBP is the only radiologic feature that can discriminate PsA from other inflammatory arthritides. This study showed the utility of plain radiographs for diagnosis of PsA.

Recent advances in imaging in psoriatic arthritis

The recent introduction of effective therapies in psoriatic arthritis (PsA) has increased the demand for efficient tools for diagnosis, monitoring and prognostication of PsA, and has caused an increased research effort within imaging in this disease. The clinical appearance of PsA is very diverse, involving the spine, sacroiliac joints, peripheral joints and/or entheses, and accordingly imaging findings vary. In the present paper, we present a review of the recent advances in imaging in PsA, focusing primarily on ultrasonography and magnetic resonance imaging of peripheral disease manifestations.

Magnetic Resonance Imaging in Psoriatic Arthritis — Update on Current Status and Future Perspectives: A Report from the GRAPPA 2010 Annual Meeting

The potential of magnetic resonance imaging (MRI) for use in clinical practice and research has gained increasing interest over the last decade. International collaborative initiatives from GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis) and/or OMERACT (Outcome Measures in Rheumatology) may contribute to facilitating research, identifying appropriate areas for use, and reaching consensus on the optimal examination technique. Accordingly, GRAPPA, a primary driver of international research in psoriasis and psoriatic arthritis (PsA), has focused on the current use and future development of MRI and other modern imaging modalities in PsA. This review, presented at the GRAPPA 2010 annual meeting, describes the current status of MRI in PsA, with a focus on its use in diagnosis, monitoring, and prediction of the disease course and treatment response. Important areas for future research are also outlined.

Assessment of synovitis in erosive osteoarthritis of the hand using DCE-MRI and comparison with that in its major mimic, the psoriatic arthritis

RATIONALE AND OBJECTIVES

To investigate the diagnostic value of high-resolution dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for assessment of synovitis in erosive osteoarthritis (EOA) of the hand and compare the results with those acquired in its potential mimic, the psoriatic arthritis (PsA).

MATERIALS AND METHODS

Twenty-six patients (17 PsA, 9 EOA) were examined at 3 T. The time course of synovial contrast uptake was measured by ROI analysis using a three-dimensional encoded spoiled gradient-echo sequence. Characteristic parameters of synovial uptake curves (time to peak [TTP], peak value, mean transit time [MTT], area under the curve [AUC], and maximum upslope) of PsA and EOA patients were compared using gamma variate analysis and calculation of the late relative enhancement 15 minutes after contrast administration.

RESULTS

Enhancement curves of PsA and EOA patients paralleled each other at comparable levels in the early phase after contrast injection without statistical difference in the following calculated characteristic curve parameters: TTP, peak value, MTT, AUC, and maximum upslope. However, significant difference was found in the late relative enhancement 15 minutes after contrast injection (P = .0275) with higher values in EOA patients.

CONCLUSION

DCE-MRI provides assessment of synovitis in both patients with EOA and PsA. Interestingly, synovial enhancement characteristics were comparable for the most part in these two disorders. However, late enhancement might help in differentiation which is essential for guiding therapy.

High-resolution interleaved water-fat MR imaging of finger joints with chemical-shift elimination

PURPOSE

To study the use of an interleaved water-fat (IWF) sequence with a custom-made radiofrequency (RF) coil for high-resolution imaging of arthritic finger joints.

MATERIALS AND METHODS

High-resolution finger magnetic resonance imaging (MRI) was performed using a custom-made dedicated RF receiver coil and an IWF sequence. A phantom, a cadaver finger specimen, and the fingers of two normal controls and six arthritic subjects were imaged with a resolution of 156 × 156 × 600 μm. The appearance of anatomic structures on the IWF images were compared with images acquired with a regular sequence. The images were reviewed by two musculoskeletal radiologists for the depiction of anatomical structures and for the presence of abnormalities.

RESULTS

The high-resolution images revealed detailed structures of the finger joints not detectable using typical clinical resolution. The IWF sequence gave more realistic depiction of subchondral bone thickness, and avoided false bone erosions displayed in the regular sequence. It also allowed better visualization of ligaments and tendons.

CONCLUSION

This pilot study shows the feasibility and the potential usefulness of high-resolution IWF imaging for finger joint evaluation. This technique may be useful for the diagnosis and treatment assessment of arthritis, and for the study of joint disease pathogenesis.

Enthesitis and Related Changes in the Knees in Seronegative Spondyloarthropathies and Skin Psoriasis: Magnetic Resonance Imaging Case-Control Study

Objective.

To describe enhanced magnetic resonance imaging (MRI) features and characteristic entheseal changes in the knees in patients with seronegative spondyloarthropathy (SpA).

Methods.

The 56 patients included 30 with psoriatic arthritis, 5 with ankylosing spondylitis, 5 with reactive arthritis, 5 with ulcerative colitis (UC), 5 with Crohn’s disease, and another 6 with skin psoriasis. Controls were 20 healthy subjects without knee complaints. MRI was performed in all participants, emphasizing entheseal sites.

Results.

Both knees were studied in 45 (80.3%) patients and one knee in 11 (19.6%). MRI showed evidence of bone marrow edema in 13 (23.2%) patients, cartilaginous erosions in 18 (32.1%), and bone erosions in 9 (16.1%). Enthesitis was found in medial collateral ligaments in 18 (32.1%), lateral collateral ligaments in 8 (14.3%), posterior cruciate ligaments in 3 (5.35%), patellar tendon in 18 (32.1%), biceps femoris insertion in 3 (5.35%), medial patellofemoral ligaments (MPFL) in 5 (8.9%), and lateral patellofemoral ligament in 1 patient (1.8%). In the UC and Crohn’s patients (n = 10), 2 had bone erosions and 5 had enthesitis. In the skin psoriasis group (n = 6), one had bone marrow edema; enthesitis was detected in 5 at the patellar tendon insertion and in one in the MPFL. Entheseal-related changes were absent in the controls.

Conclusion.

This is the first study showing entheseal-related changes in the knees in patients with inflammatory bowel disease or skin psoriasis without clinical arthritis. Enthesitis of the knee on MRI may be an early finding in SpA.

MR imaging of early rheumatoid arthritis

Early diagnosis and treatment have been recognized as essential for improving clinical outcomes in patients with early rheumatoid arthritis. However, diagnosis is somewhat difficult in the early stages of the disease because the diagnostic criteria were developed from data obtained in patients with established rheumatoid arthritis and therefore are not readily applicable. Magnetic resonance (MR) imaging is increasingly being used in the assessment of rheumatoid arthritis due to its capacity to help identify the key pathologic features of this disease entity at presentation. MR imaging has demonstrated greater sensitivity for the detection of synovitis and erosions than either clinical examination or conventional radiography and can help establish an early diagnosis of rheumatoid arthritis. It also allows the detection of bone marrow edema, which is thought to be a precursor for the development of erosions in early rheumatoid arthritis as well as a marker of active inflammation. In addition, MR imaging can help differentiate rheumatoid arthritis from some clinical subsets of peripheral spondyloarthropathies by allowing identification of inflammation at the insertions of ligaments and tendons (enthesitis).

The role of dynamic contrast-enhanced MRI in the differential diagnosis of psoriatic and rheumatoid arthritis

OBJECTIVE

The purpose of this study was to investigate the role of dynamic contrast-enhanced MRI in the differential diagnosis of psoriatic and rheumatoid arthritis in the hand and wrist.

SUBJECTS AND METHODS

Forty-five consecutive patients (31 patients with rheumatoid arthritis and 14 patients with psoriatic arthritis) were examined in a 3-T whole-body MR unit. After contrast injection, a 3D encoded spoiled gradient-echo sequence was used for measurement of the time course of contrast-medium uptake in the synovial tissue. On the basis of the gained uptake curves, the rate of early enhancement was calculated after 35 and 52 seconds, and the relative enhancement rate was calculated after 35 seconds, 52 seconds, 3 minutes, and 15 minutes (late enhancement). Dynamic contrast-enhanced MRI rates of patients with rheumatoid arthritis and psoriatic arthritis were compared and correlated with laboratory and clinical data.

RESULTS

A statistically significant difference between the two groups was found regarding the relative enhancement rate after 15 minutes (p < 0.01). In contrast, no difference in relative enhancement rate was found 35 seconds, 52 seconds, or 3 minutes after contrast injection (p = 0.695, p = 0.573, and p = 0.278, respectively). Regarding the rate of early enhancement at 35 and 52 seconds, no significant difference between patients with rheumatoid arthritis and those with psoriatic arthritis was found. Significant correlations were found between inflammatory parameters and dynamic contrast-enhanced parameters in patients with rheumatoid arthritis but not in those with psoriatic arthritis.

CONCLUSION

Fifteen minutes after contrast injection, a statistically significant difference between rheumatoid arthritis and psoriatic arthritis was found in synovial enhancement that might play an important role in differentiating the two diseases.

High-resolution uniform MR imaging of finger joints using a dedicated RF coil at 3T

PURPOSE

To develop a dedicated radiofrequency (RF) coil for high-resolution magnetic resonance imaging (MRI) of finger joints at 3T to improve diagnostic evaluation of arthritic diseases.

MATERIALS AND METHODS

A dedicated cylindrical RF receive coil was developed for imaging finger joints at 3T. A planar coil, a saddle coil, and a 1.5T coil with similar design as the dedicated coil were also constructed to compare imaging performance with the dedicated coil. A phantom was used for quantitative evaluation. Three-dimensional images were obtained on four subjects and a cadaver finger specimen using isotropic resolution of 160 mum in 9:32 minutes. The images were reviewed by two musculoskeletal radiologists.

RESULTS

The dedicated finger coil provided higher signal-to-noise and greater signal uniformity than the other coils. It supported high-resolution imaging that demonstrated anatomical details of the entire finger joint, and in the subject study revealed abnormalities not detectable by traditional clinical resolution.

CONCLUSION

The dedicated finger coil optimizes the potential advantages of 3T scanners compared to lower field magnets. Use of this coil should facilitate early diagnosis, improve assessment of treatment response, and provide better understanding of basic mechanisms that underlie arthritis.

Can Magnetic Resonance Imaging Differentiate Undifferentiated Arthritis Based on Knee Imaging?

Objective.

To compare findings as observed on enhanced magnetic resonance imaging (MRI) of the knee joints, in oligoarticular-undifferentiated arthritis (UA) in those with established rheumatoid arthritis (RA) and spondyloarthropathy (SpA).

Methods.

A total of 55 patients with knee arthritis were consecutively recruited for the study, including 25 with undifferentiated oligoarthritis of the knee joint(s), 15 fulfilling the American College of Rheumatology criteria for RA and 15 with SpA. Laboratory investigations included erythrocyte sedimentation rate, C-reactive protein, complete blood count, aspartate aminotransferase, alanine aminotransferase, serum creatinine, and urine analysis. In all patients in the UA and in the RA group, rheumatoid factor and anti-CCP2 antibody (ELISA) were tested. All patients underwent enhanced MRI of the more symptomatic knee. All groups were compared in terms of demographics, laboratory investigations, and MRI findings.

Results.

Synovial thickness differed significantly in the RA group compared to UA and SpA groups (p < 0.001). The RA group showed a higher rate of bony and cartilaginous erosions and bone marrow edema compared to UA and SpA groups (p < 0.001). Enthesitis was found in all patients in the SpA group (100%) and differed from RA and UA groups (p < 0.001).

Conclusion.

Patients with RA showed more destructive changes in terms of synovial thickening, bone marrow edema, cartilaginous and bone erosions compared to UA and SpA groups. Enthesitis is a common feature on MRI in SpA, while absent in the RA and UA groups. This latter finding may have important clinical implications for classification purposes, and can help to determine the evolving pattern of patients with UA of the knee joint.

Tenosynovitis of the flexor tendons of the hand detected by MRI: an early indicator of rheumatoid arthritis

OBJECTIVE

To evaluate the potential of MRI of finger and wrist joints for diagnosing early RA. MRI was evaluated as a stand-alone tool and in combination with ACR criteria and serum markers such as RF.

METHODS

Ninety-nine patients (31 men, 68 women; median age 46 years) with unspecified arthritis or suspected RA and negative X-ray findings were included. MR images of the hand and wrist of these patients were retrospectively evaluated for the presence of synovitis, erosions and tenosynovitis. The clinical diagnosis (early RA or non-RA) was made by a rheumatologist after clinical follow-up for 6-41 months. Clinical and laboratory data were collected from all patients.

RESULTS

Fifty-eight patients had a clinical diagnosis of RA and 41 were diagnosed as non-RA. Step-wise logistic regression of all MR parameters evaluated identified tenosynovitis of the flexor tendons to be the most powerful predictor of early RA (sensitivity = 60%, specificity = 73%). Including ACR criteria in the analysis, positive serum RF and tenosynovitis were the strongest predictors of early RA (sensitivity = 83%, specificity = 63%). When serum anti-cyclic citrullinated peptides (CCP), ANA and CRP were included as additional parameters, anti-CCP and flexor tenosynovitis were the strongest predictors of early RA (sensitivity = 79%, specificity = 73%).

CONCLUSIONS

Flexor tenosynovitis diagnosed by MRI of the hand is a strong predictor of early RA. Combining flexor tenosynovitis on MRI with positive serum anti-CCP or positive RF is an even stronger predictor of early RA.

Diagnosis of peripheral psoriatic arthritis: recommendations for clinical practice based on data from the literature and experts opinion

OBJECTIVE

To propose French recommendations for the clinical, biological and radiological diagnosis of peripheral psoriatic arthritis (PsA) in daily practice based on data from the literature and expert opinion.

METHOD

The strategy was the following: the choice of four questions, concerning this topic by the scientific committee according to the Delphi method, forming the basis of the recommendations. The Systematic literature research based on Medline, Cochrane and abstracts from the annual meetings of the French society of rheumatology (SFR), American college of rheumatology (ACR) and European ligue against rheumatism (EULAR). An experts committee of rheumatologists elaborated, validated specifying the strength and the degree of agreement of each recommendation.

RESULTS

The questions selected were: (1) What clinical data should be collected to assist in the diagnosis of psoriatic arthritis? (2) What laboratory tests, immunological tests, and genetic tests should be performed to assist in the diagnosis of psoriatic arthritis? (3) What are the radiological investigations useful in the diagnosis of psoriatic arthritis? (4) What classification and/or diagnosis criteria can assist in the diagnosis of psoriatic arthritis? A literature search identified 1627 abstracts and 33 articles were included and analyzed. Four recommendations relative to the diagnosis were drafted and validated by a final vote of the experts committee.

CONCLUSION

Recommendations concerning the diagnosis of PsA for daily practice were developed and validated on the basis of data from the literature and expert opinion. They should help to establish the diagnosis of PsA in daily practice.

MRI findings of juvenile psoriatic arthritis

OBJECTIVE

The aim of this study was to describe the magnetic resonance imaging (MRI) features of juvenile psoriatic arthritis (JpsA) in children in order to facilitate early diagnosis and proper management.

MATERIALS AND METHODS

Two pediatric radiologists retrospectively reviewed in consensus a total of 37 abnormal MRI examinations from 31 pediatric patients (nine boys, 22 girls; age range 1-17 years; mean age 9.4 years) who had a definite diagnosis of JpsA and underwent MRI. Each MRI was evaluated for synovium abnormality (thickening and enhancement), joint effusion (small, moderate, and large), bone marrow abnormality (edema, enhancement, and location of abnormality), soft tissue abnormality (edema, enhancement, atrophy, and fatty infiltration), tendon abnormality (thickening, edema, tendon sheath fluid, and enhancement), and articular abnormality (joint space narrowing and erosion). The distribution of abnormal MRI findings among the six categories for the 37 MRI examinations was evaluated. The number of abnormal MRI findings for each MRI examination was assessed. Age at MRI examination and all six categories of abnormal MRI findings according to gender were evaluated.

RESULTS

There were a total 96 abnormal MRI findings noted on 37 abnormal MRI examinations from 31 pediatric patients. The 37 abnormal MRI examinations included MRI of the hand (n = 8), knee (n = 8), ankle (n = 5), pelvis (n = 5), temporomandibular joint (n = 4), wrist (n = 3), foot (n = 2), elbow (n = 1), and shoulder (n = 1). Twenty-eight diffuse synovial thickening and/or enhancement were the most common MRI abnormality (29.2%). Joint effusion comprised 22 abnormal MRI findings (22.9%). There were 16 abnormal MRI bone marrow edema and/or enhancement findings (16.7%), and in seven (7.3%) the edema involved non-articular sites. Soft tissue abnormality manifested as edema and/or enhancement constituted 14 abnormal MRI findings (14.5%). There were ten MRI abnormalities (10.4%) involving tendons. Articular abnormality seen as joint space narrowing and/or bone erosion comprised six abnormal MRI findings (6.2%). Most MRI examinations had more than one abnormal finding (84%). Age at which MRI examinations were performed was not significantly different between boys and girls. All six categories of abnormal MRI findings were not significantly different between boys and girls.

CONCLUSION

Children with JpsA typically present with more than one abnormal finding on their MRI studies. While synovial abnormality is the most common MR finding in children with JpsA, multi-focal bone marrow edema and enhancement at both articular and non-articular sites are also notable findings in children with JpsA. The rate of articular abnormality is much lower in children with JpsA in comparison to adults with psoriatic arthritis. Our findings suggest that MRI can play a useful role in the diagnosis and ongoing assessment of this uncommon, though important, pediatric rheumatologic disorder.

Psoriatic arthritis: clinical spectrum and diagnostic procedures

Psoriatic arthritis presents with a broad clinical spectrum of symptoms. Symmetrical polyarthritis with joint pain and joint swelling is one pattern of clinical manifestations that often indicates erosive progressive disease. Unlike in rheumatoid arthritis, the distal interphalangeal joints are regularly involved. Sometimes, the disease focuses on the larger joints of the lower extremities; iliosacral and intervertebral joints and tendons can also be involved. Thus, inflammatory back pain as well as any other prolonged joint pain in a patient with psoriasis is suspicious of psoriatic arthritis. This article reviews the clinical spectrum and diagnostic procedures that can lead to the diagnosis of psoriatic arthritis.