Ultrasonography in the diagnosis and management of patients with inflammatory arthritides

Peripheral Spondyloarthritis: Conceptualization and Diagnosis as a Distinct Rheumatologic Subset of Disease

Peripheral spondyloarthritis (pSpA) encompasses multiple entities affecting the musculoskeletal system with classic findings of synovitis, enthesitis, and tenosynovitis. It remains poorly defined when compared with the axial spondyloarthritides due to nonspecific symptoms, ill-defined imaging findings, and lack of specific testable biomarkers. Previous research has tried to distinguish between the two disease entities using clinical presentations, scoring systems, and radiographic findings; however, overlap remains. We summarize the current classification of pSpA, imaging findings, and the distinction between these entities and axial spondyloarthritis.

Mini-enthesitis can differentiate rheumatoid arthritis from psoriatic arthritis: A comprehensive comparative ultrasound study of the joints and mini-entheses of the hands

Objectives

This study aimed to explore whether hand ultrasonography (USG) could differentiate between rheumatoid arthritis (RA) and psoriatic arthritis (PsA) patients.

Patients and methods

A comprehensive USG of 35 PsA patients (13 males, 22 females; mean age: 60.9±8.4 years; range, 53 to 69 years), 30 RA patients (10 males, 20 females; mean age: 58.4±10.0 years; range, 50 to 61 years), and 20 healthy controls (5 males, 15 females; mean age: 55.6±5.8 years; range, 50 to 61 years) was performed with assessments of the wrist, tendons, mini-entheses, and joints of the second and third finger, both on gray scale and power Doppler USG.

Results

Two hundred forty-five joints of PsA patients, 210 joints of RA patients, and 120 joints of healthy controls were assessed by USG. Wrist joint synovitis and tenosynovitis of the extensor digitorum communis and extensor carpi ulnaris tendon were significantly more common in RA patients compared to PsA patients (p<0.001), detected in 93.30%, 63.30%, and 73.30% versus 57.10%, 14.30%, and 2.90%, respectively. The incidence of tenosynovitis of the flexor tendons at the wrist level was significantly higher in RA patients (p=0.003), detected in 36.70% versus 14.30%. Paratenonitis of the finger extensor tendon at the metacarpophalangeal joints was significantly more prevalent in PsA patients, detected in 85.70% versus 3.30% (p<0.001). Central slip enthesitis at the proximal interphalangeal joint and enthesitis of the distal slip of the extensor tendon at the second and third distal phalanx were exclusively found in PsA patients, occurring in 45.70%, 91.40%, and 71.30%, respectively (p<0.001). Flexor tenosynovitis and pseudotenosynovitis were significantly more prevalent in PsA patients (65.70% and 57.10%, respectively) compared to RA patients (16.70% and 0.00%, respectively; p<0.001). PsA patients had significantly higher thickness of the A1 pulley compared to RA patients (p<0.001).

Conclusion

Mini-enthesitis is a hallmark USG finding in PsA.

Imaging Response to Treatment in Rheumatology

This article highlights the crucial role of various imaging techniques in the diagnosis and monitoring of rheumatologic diseases. It provides an overview of the different modalities available for imaging rheumatic diseases, the disease processes they are able to demonstrate, and their utility in the monitoring response to therapy. It emphasizes the need for a multifaceted approach that combines radiography, ultrasound, MR imaging, and PET imaging to gain a comprehensive understanding of disease progression and treatment response. Standardized grading systems along with quantitative imaging techniques are playing an increasing role in monitoring disease activity and assessing response to therapy.

Ultrasound detected synovitis, tenosynovitis and erosions in hand and wrist joints: a comparative study between rheumatoid and psoriatic arthritis

Objectives

Musculoskeletal ultrasound (MSUS) has been introduced as a valuable simple imaging tool for arthritis. The objective was to assess the role of ultrasound (US) in the differential diagnosis between rheumatoid arthritis (RA) and psoriatic arthritis (PsA) at the wrist and hand joints and tendons.

Material and methods

Thirty-five patients (20 RA and 15 PsA) with symptomatic involvement of at least one of the hand and/or wrist joints for > 6 weeks were included. Bilateral wrists (distal radioulnar, radiocarpal and midcarpal joints), hands (1^st–5^th metacarpophalangeal [MCP], 2ⁿd–5^th proximal interphalangeal [PIP] and 1^st–5^th distal interphalangeal [DIP] joints), flexor tendons and extensor compartments at the level of the wrist joint were examined sonographically. Synovial hypertrophy, joint effusion, erosions and tenosynovitis were diagnosed according to Outcome Measures in Rheumatology definitions. The findings were correlated with clinical, laboratory and disease activity indices.

Results

Among 680 and 510 joints examined in RA and PsA respectively, certain US features such as synovitis and erosions at the DIP were exclusively detected in PsA (p < 0.001). Synovitis was frequently detected at the distal radioulnar joints (DRUJ) in RA in comparison to PsA patients (52.5% vs. 26.7% respectively, p = 0.029). Joint effusion was more frequently detected at radiocarpal and midcarpal joints in RA compared to PsA (p = 0.047, 0.039 respectively), whereas erosions were significantly more frequently detected at radiocarpal joints in RA versus PsA patients (45% vs. 20% respectively, p = 0.029). Tenosynovitis was significantly more frequently detected at the extensor tendons in RA and at the flexor tendons in PsA patients (p = 0.021, 0.022 respectively).

Conclusions

There are significant differences in the musculoskeletal US findings of the hand and wrist that joints help to distinguish between RA and PsA.

Is seronegative rheumatoid arthritis true rheumatoid arthritis? A nationwide cohort study

OBJECTIVES

The classification of seronegative arthritides can be challenging. Our aim was to examine the incidence of SpA diagnosis among patients initially diagnosed as seronegative RA.

METHODS

Using nationwide Finnish registers from social insurance institutions, we identified all adult patients who were diagnosed with incident seronegative RA [International Classification of Diseases (ICD)-10 code M06] from 1 January 2000 to 31 December 2014. The patients whose diagnoses subsequently changed to the ICD-10 codes of SpA (M07, M45, M46, K50 and K51) were identified in the national care register, until 31 December 2016.

RESULTS

A total of 9784 adult seronegative RA patients were identified. Of these, 564 patients had their diagnosis subsequently changed to SpA: 275 (48.7%) patients with PsA, 245 (43.4%) patients with axial SpA and 44 (7.8%) patients with diagnoses related to IBD. The cumulative incidence of SpA diagnoses in 15 years was 10.4% (95% CI 8.9, 12.1) and 8.1% (95% CI 7.1, 9.3) in men and women, respectively.

CONCLUSION

This study calls for vigilance in seronegative RA patients, especially those with more atypical presentations, since the diagnosis could change. The possibility of SpA diagnosis should be considered and specifically looked for, as this could impact on management and response to treatment.

Ultrasound-Verified Peripheral Arthritis in Patients with HLA-B*35 Positive Spondyloarthritis

Background: We aimed to investigate possible association between the HLA-B*35 allele and peripheral arthritis, tenosynovitis and enthesitis. Methods: Ultrasound of peripheral joints and tendons was performed in 72 HLA-B*35 positive patients with preliminary diagnosis of undifferentiated axial form of spondyloarthitis and joint and tendon pain. Patients with other known types of axial and peripheral spondyloarthritis were excluded as well as patients with other known types of arthritis. Results: Pathological changes were found in the joints of 33 (46%) patients and on the tendons in 13 (18%) patients. The most common ultrasound findings were joint effusion and synovial proliferation with positive power Doppler signal grade 1. The most common ultrasound finding in patients with painful tendons was tenosynovitis. A higher disease activity and an increased incidence of elevated CRP (≥5 mg/L) were more often observed in the group with positive ultrasound findings. Conclusion: In this study, we showed that the HLA-B*35 allele could be a potential risk factor for developing peripheral arthritis, but not for tenosynovits and enthesitis in patients with the undifferentiated axial form of spondyloarthritis. This result may influence the follow up of these patients, especially since it gives us an opportunity to consider the use of different types of DMARDs in the treatment of these patients.

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.

Hand ultrasound patterns in rheumatoid and psoriatic arthritis: the role of ultrasound in the differential diagnosis

Many rheumatic diseases may present with an inflammatory joint syndrome, affecting the small joints of the hands, of which rheumatoid (RA) and psoriatic arthritis (PsA) being one of the most common. The aim of this systematic review was to focus on the literature evidence regarding the added value of ultrasound (US) of the hand in the differential diagnosis between RA and PsA. Pubmed and Scopus were searched to identify original manuscripts, published in the last 20 years utilising ultrasonography to reveal specific hand US patterns. Studies were eligible if they: (1) included adults (over 18 years) with a diagnosis of RA/PsA; (2) were published in the English language; (3) were published in peer-reviewed journals; (4) included description of the US machine; (5) used US for assessment of hand joints, periarticular tissues and nails. The search yielded 322 published studies, of which 16 were deemed relevant and were included in the present study. Overall, there was heterogeneity with regard to the pathology examined. Based on the included studies analysis, hand US patterns have several basic features to be considered-location of gray scale (GS) inflammatory findings, involvement of periarticular soft tissue, distribution and extent of Doppler signal (intra- and peri-articular), bone reaction, shape and location of erosions, involvement of tendons without synovial sheath, involvement of enthesis and nail abnormalities. Future research could focus on determining the sensitivity and specificity of the different US detected hand patterns in patients with early arthritis.

The importance of ultrasound in identifying and differentiating patients with early inflammatory arthritis: a narrative review

Early differentiation between different types of inflammatory arthritis and subsequent initiation of modern treatments can improve patient outcomes by reducing disease activity and preventing joint damage. Routine clinical evaluation, laboratory testing, and radiographs are typically sufficient for differentiating between inflammatory and predominantly degenerative arthritis (e.g., osteoarthritis). However, in some patients with inflammatory arthritis, these techniques fail to accurately identify the type of early-stage disease. Further evaluation by ultrasound imaging can delineate the inflammatory arthritis phenotype present. Ultrasound is a noninvasive, cost-effective method that enables the evaluation of several joints at the same time, including functional assessments. Further, ultrasound can visualize pathophysiological changes such as synovitis, tenosynovitis, enthesitis, bone erosions, and crystal deposits at a subclinical level, which makes it an effective technique to identify and differentiate most common types of inflammatory arthritis. Limitations associated with ultrasound imaging should be considered for its use in the differentiation and diagnosis of inflammatory arthritides.

Psoriatic Arthritis: What is Happening at the Joint?

Psoriatic arthritis (PsA) is a heterogeneous and inflammatory disease with diverse clinical manifestations, including psoriasis, nail psoriasis, peripheral joint disease, axial joint disease, enthesitis, and dactylitis. Typically, this varied clinical presentation complicates the clinician's ability to distinguish PsA from other forms of arthritis. In the synovium of individuals with PsA, upregulation of the genes WNT3A, BMPR2, and TGFBR1 results in bone erosion and new bone formation, a pattern unique to the disease. Additionally, genes associated with angiogenesis and vascularization such as VEGF and TGFB1 facilitate inflammation and joint damage. Gross pathogenesis of PsA is driven by proinflammatory cytokines, and key cytokines affecting joint structures include tumor necrosis factor-α, interleukin (IL)-6, IL-17A, IL-21, IL-22, and IL-23. Early diagnosis is critical for providing treatment that prevents irreversible disease progression and function loss. This narrative review discusses differentiation of PsA from other forms of arthritis. Additionally, we detail the role of cytokines at the joint in mediating PsA pathogenesis.Funding: Novartis Pharmaceuticals Corporation.

Distinguishing rheumatoid arthritis from psoriatic arthritis

Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) have key differences in clinical presentation, radiographic findings, comorbidities and pathogenesis to distinguish between these common forms of chronic inflammatory arthritis. Joint involvement is typically, but not always, asymmetric in PsA, while it is predominantly symmetric in RA. Bone erosions, without new bone growth, and cervical spine involvement are distinctive of RA, while axial spine involvement, psoriasis and nail dystrophy are distinctive of PsA. Patients with PsA typically have seronegative test findings for rheumatoid factor (RF) and cyclic citrullinated peptide (CCP) antibodies, while approximately 80% of patients with RA have positive findings for RF and CCP antibodies. Although there is overlap in the pathogenesis of PsA and RA, differences are also present that affect the efficacy of treatment. In PsA, levels of interleukin (IL)-1β, IL-6, IL-17, IL-22, IL-23, interferon-γ and tumour necrosis factor-α (TNF-α) are elevated, and in RA, levels of IL-1, IL-6, IL-22, IL-33, TNF-α, chemokine ligand 11 and chemokine C-X-C motif ligand 13 are elevated. Differences in the pathogenesis of RA and PsA translate into some variances in the specificity and efficacy of therapies.

[Fibroblasts as pathogenic cells in rheumatic inflammation]

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovitis, synovial hyperplasia and progressive degeneration of affected joints. These processes are mediated by cells of the immune system as well as by synovial fibroblasts (RASF) originating from the lining layer of the synovium. In this scenario RASFs display an activated phenotype: they show an altered expression of adhesion molecules which allows attachment to articular cartilage and by synthesis of proteases they mediate progressive cartilage and bone destruction. Furthermore, they produce various cytokines and chemokines, which are essential for promoting the inflammatory response. In recent years it has become evident that RASFs not only passively respond to the proinflammatory milieu in the joints of RA patients but also actively contribute by the overproduction of several cytokines and chemokines. These proinflammatory cytokines trigger the transformation of RASFs into an aggressive and invasive phenotype. Additionally, the primarily altered genuine RASFs are actively involved in the recruitment and activation of immune cells. Taken together, they are key players in the development of the well-known chronic, destructive inflammatory response in joints affected by RA.

The role of imaging modalities in the diagnosis, differential diagnosis and clinical assessment of peripheral joint osteoarthritis

Peripheral joint osteoarthritis (OA) is predominantly a clinical diagnosis, though imaging may provide confirmation and aid with differential diagnosis where there is clinical doubt. Whilst radiographs (X-rays (XR)) are usually the first-line imaging modality selected, magnetic resonance imaging (MRI), ultrasound and computed tomography (CT) may all have a valuable role in assessing a person with OA, although each has its particular advantages and disadvantages. MRI is of particular use for diagnosing bone conditions that may cause a rapid increase in symptoms, such as avascular necrosis (AVN) or a subchondral insufficiency fracture (SIF), while providing concomitant soft tissue assessment. Ultrasound offers rapid assessment of peripheral joints and can easily assess for features of inflammatory arthritis. CT is faster to perform than MRI and can also image the subchondral bone, but does involve ionising radiation. Selecting the correct imaging modality, in the context of its advantages when visualising a specific joint (e.g., hand vs knee) and with clinical context in mind, will enhance the added value of imaging in clinical practice.