Peritenon Extensor Tendon Inflammation in Psoriatic Arthritis Is an Enthesitis-related Lesion

Validation and incorporation of digital entheses into a preliminary GLobal OMERACT Ultrasound DActylitis Score (GLOUDAS) in psoriatic arthritis

OBJECTIVES

The main objective was to generate a GLobal OMERACT Ultrasound DActylitis Score (GLOUDAS) in psoriatic arthritis and to test its reliability. To this end, we assessed the validity, feasibility and applicability of ultrasound assessment of finger entheses to incorporate them into the scoring system.

METHODS

The study consisted of a stepwise process. First, in cadaveric specimens, we identified enthesis sites of the fingers by ultrasound and gross anatomy, and then verified presence of entheseal tissue in histological samples. We then selected the entheses to be incorporated into a dactylitis scoring system through a Delphi consensus process among international experts. Next, we established and defined the ultrasound components of dactylitis and their scoring systems using Delphi methodology. Finally, we tested the interobserver and intraobserver reliability of the consensus- based scoring systemin patients with psoriatic dactylitis.

RESULTS

32 entheses were identified in cadaveric fingers. The presence of entheseal tissues was confirmed in all cadaveric samples. Of these, following the consensus process, 12 entheses were selected for inclusion in GLOUDAS. Ultrasound components of GLOUDAS agreed on through the Delphi process were synovitis, tenosynovitis, enthesitis, subcutaneous tissue inflammation and periextensor tendon inflammation. The scoring system for each component was also agreed on. Interobserver reliability was fair to good (κ 0.39-0.71) and intraobserver reliability good to excellent (κ 0.80-0.88) for dactylitis components. Interobserver and intraobserver agreement for the total B-mode and Doppler mode scores (sum of the scores of the individual abnormalities) were excellent (interobserver intraclass correlation coefficient (ICC) 0.98 for B-mode and 0.99 for Doppler mode; intraobserver ICC 0.98 for both modes).

CONCLUSIONS

We have produced a consensus-driven ultrasound dactylitis scoring system that has shown acceptable interobserver reliability and excellent intraobserver reliability. Through anatomical knowledge, small entheses of the fingers were identified and histologically validated.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Sex-Based Differences in Sonographic and Clinical Findings Among Patients With Psoriatic Arthritis

OBJECTIVE

To investigate sex-based sonographic differences in patients with psoriatic arthritis (PsA).

METHODS

The study population included consecutive prospectively recruited patients with PsA, as determined by the CASPAR (Classification for Psoriatic Arthritis) criteria, who underwent clinical and physical examinations, followed by a detailed ultrasound (US) evaluation (greyscale and Doppler). US evaluation included 52 joints, 40 tendons, and 14 points of entheses (Modified Madrid Sonographic Enthesis Index [MASEI] plus lateral epicondyles) performed by an experienced sonographer blinded to the clinical data. The US score was based on the summation of a semiquantitative score for synovitis, tenosynovitis, and enthesitis. The US enthesitis score was categorized into inflammatory lesions (ie, hypoechogenicity, thickening, bursitis, and Doppler) and structural lesions (ie, enthesophytes/calcifications and erosions).

RESULTS

The study population of 158 patients included 70 males and 88 females. The males had higher rates of employment (P = 0.01), Psoriasis Area and Severity Index scores (P = 0.04), and mean swollen joint counts (P = 0.04). The total US score and its subcategory scores-the synovitis and tenosynovitis scores-were similar for both sexes, whereas the total enthesitis score and its subcategory score-the inflammatory enthesitis score-were significantly higher for the males compared to the females (P = 0.01 and P = 0.005, respectively). Hypoechogenicity, thickening, and enthesophytes were more prevalent in males compared to females (P < 0.05). Multivariate ordinal logistic regression models showed that male sex was associated with a higher US inflammatory enthesitis score compared to female sex (odds ratio 1.96, P = 0.02).

CONCLUSION

Sonographic enthesitis was more prevalent in males compared to females with PsA. These differences were not reflected by enthesitis disease activity scores derived from clinical assessment.

Role of diagnostic imaging in psoriatic arthritis: how, when, and why

Psoriasis is a common skin disease. Up to 30% of patients with psoriasis develop psoriatic arthritis (PsA) resulting, by far, the most prevalent coexisting condition. Heterogeneity of clinical and radiological presentation is a major challenge to diagnosis of PsA. Initial reports about PsA emphasized a benign course in most patients, but it is now recognized that psoriatic arthritis often leads to impaired function and a reduced quality of life. PsA is a progressive disease characterized by diverse clinical features, often resulting in diagnostic delay and treatment that are associated with poor clinical and structural outcomes. New effective treatments may halt PsA progression, and consequently, treatment goals have evolved from simple reduction of pain to achieving full remission or minimal disease activity. This emerging treat-to-target strategy paradigm emphasize a need for early diagnosis; sensitive imaging techniques may be of value in this process. While radiography and CT depict structural damage, US and MRI have emerged as helpful tools to evaluate magnitude and severity of active inflammatory lesions. This review aims to describe the role of imaging modalities in diagnosis, follow-up and prognosis of PsA.

Enthesitis in Psoriatic Arthritis, the Sonographic Perspective

Purpose of Review

To provide an overview of the ultrasound (US) studies focusing on enthesitis in psoriatic arthritis (PsA).

Recent Findings

Last-generation US equipment has demonstrated the ability to detect subtle morphostructural and vascular abnormalities at entheseal level. US is able to identify pathologic changes in both “classical” (i.e., the site of attachment of tendons, ligaments, and joint capsules into the bone) and “functional” entheses (i.e., anatomical regions where tendons or ligaments wrap around bony pulleys).

Summary

US has the potential to be the first-line method in the assessment of enthesitis. In the present review we critically discussed the current definitions of US enthesitis, the scoring systems, and the main fields of application (i.e., the detection of enthesitis in PsA and psoriasis, the identification of different disease subsets, and the assessment of response to treatment).

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.

A Systematic Review of the Inclusion of Non-Inflammatory Ultrasonographic Enthesopathy Findings in Enthesitis Scoring Indices

Ultrasound has advanced the diagnosis and management of patients with inflammatory rheumatic conditions. It can be used to identify and monitor enthesitis, a cardinal feature of spondyloarthropthies. Several enthesitis scoring systems utilizing ultrasound to determine entheseal involvement have been developed. These scoring systems generally rely on determining the presence or absence of erosions, tendon enlargement, power Doppler signal, or enthesophytes. This systematic review identified ultrasound scoring systems that have been utilized for evaluating enthesitis and what key components derive the score. Review of these scoring systems, however, demonstrated confounding as some of the score components including enthesophytes may be seen in non-inflammatory conditions and some components including erosions can be seen from chronic damage, but not necessarily indicate active inflammatory disease. What is furthermore limiting is that currently there is not an agreed upon term to describe non-inflammatory enthesopathies, further complicating these scoring systems. This review highlights the need for a more comprehensive ultrasound enthesopathy scoring index.

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.

Visualization of Enthesitis by Ultrasound: a Key Diagnostic Tool in Spondyloarthropathy Diagnosis and Management

PURPOSE OF REVIEW

The purpose of this review is to report on the current status of evaluation of enthesitis with sonography. Sonography can visualize peripheral entheses in great detail since most of them are superficial. Visualization of entheses has provided insights into the pathophysiology of enthesitis and highlighted the interconnectivity of stress dissipation mechanisms about the enthesis. The primary use of entheseal sonography presently revolves around diagnostic use.

RECENT FINDINGS

There is increasing awareness of biomechanical confounders that lead to entheseal changes, which are more prevalent in males, patients with higher body mass index, and those who are more active-though there are several approaches to mitigate biomechanical confounders in sonographic evaluation. Entheseal sonography may also provide prognostic information in predicting the severity of axial syndesmophyte formation. Although entheseal outcome scoring systems are available, there is sparse data on its use as an outcome tool, and hence, this is a fertile area for future research.

The management of enthesitis in clinical practice

PURPOSE OF REVIEW

Enthesitis is a hallmark feature of the spondyloarthropathies (SpA). This review provides an overview of recent insights on diagnosis and management of enthesitis.

RECENT FINDINGS

Recent studies support the use of imaging for diagnosis because of its higher sensitivity and specificity compared with clinical examination. Several new MRI and ultrasound scoring systems have been developed for enthesitis, which may facilitate the use of imaging in research. Enthesitis has been evaluated as a primary study outcome mainly in psoriatic arthritis (PsA); however, the use of different indices and definitions of improvement limits comparison across studies. There is very limited information about the efficacy of synthetic disease modifying antirheumatic drugs (DMARDs) for the treatment of enthesitis. In contrast, targeted and biologic DMARDs have all shown efficacy in treating enthesitis compared with placebo. There have been only a few head-to-head trials that compared two different cytokine inhibitors for the treatment of enthesitis. Preliminary data suggest that targeting IL-17 or IL12/23 may be more efficacious for controlling enthesitis than TNF inhibition.

SUMMARY

Emerging data suggest interleukin-17 and 12/23 inhibitors may be the first choice in PsA patients with enthesitis. Further head-to-head studies are needed before making definitive recommendations.