Ultrasound Evaluation of the Entheses in Daily Clinical Practice during Tumor Necrosis Factor-α Blocking Therapy in Patients with Ankylosing Spondylitis

Radiographic entheseal lesions of the pelvic region are more prevalent in radiographic axSpA than in age- and sex-matched controls and are associated with more severe spinal disease

OBJECTIVES

In axial spondyloarthritis (axSpA), entheseal involvement is common, which contributes significantly to disease burden and may also lead to structural damage. Although radiographs of the pelvis are widely available in axSpA, information on entheseal damage and associated characteristics are lacking. Therefore, we assessed the prevalence of radiographic entheseal lesions at the pelvic region in radiographic (r-) axSpA compared with controls and explored associations with patient and disease characteristics.

METHODS

Pelvic radiographs of 167 consecutive r-axSpA patients were randomized with 100 pelvic radiographs from age- and sex-matched controls. Radiographs were blinded for patient information and sacroiliac joints and bilaterally evaluated for erosions/cortical irregularities, enthesophytes, and calcifications by two trained readers at the greater and lesser trochanter, os ischium, and iliac crest.

RESULTS

Entheseal lesions were observed in 127 (76%) of r-axSpA patients and 58 (58%) controls. R-axSpA patients showed significantly more (bilateral) entheseal lesions than controls at all entheseal sites. Most lesions were found at the os ischium, erosions/cortical irregularities were most prevalent, and calcification was the most specific lesion in r-axSpA. Patients with lesions were significantly older, had longer symptom duration, and more severe spinal radiographic damage than patients without lesions. Enthesophytes were found significantly more often in patients with body mass index (BMI) ≥ 25.

CONCLUSION

Structural entheseal lesions observed at pelvic radiographs are not specific but occur often in r-axSpA patients. Treating physicians should keep in mind that these entheseal lesions are associated with more severe axial disease and high BMI which may be relevant for treatment decisions. Key Points • Pelvic radiographic entheseal lesions are significantly more prevalent in r-axSpA patients than in controls. • Radiographic entheseal lesions are associated with longer symptom duration and more spinal radiographic damage. • Pelvic enthesophytes are found significantly more often in r-axSpA patients with BMI ≥ 25.

Achilles enthesitis on physical examination leads to worse outcomes after 2 years of follow up in patients with ankylosing spondylitis from REGISPONSER-AS registry

BACKGROUND

Enthesitis represents one of the most important peripheral musculoskeletal manifestations in patients with axial spondyloarthritis (axSpA). However, studies specifically evaluating Achilles tendon enthesitis and its impact over time are scarce. The objectives of this study were to evaluate the impact of Achilles' tendon enthesitis found at baseline during physical examination on the outcome measures after 2 years of follow-up in patients with ankylosing spondylitis (AS).

METHODS

This was an observational and prospective study conducted during 2 years of follow-up in the REGISPONSER-AS registry. Linear regression models adjusted for age, body mass index (BMI), and anti-TNF intake were conducted to evaluate the association between the presence of Achilles enthesitis at baseline and the patient-reported outcome (PRO) scores at baseline. The impact of this feature on PROs over 2 years of follow-up was evaluated using mixed models for repeated measures adjusted for age, BMI, and anti-TNF intake.

RESULTS

Among the 749 patients included, 46 patients (6.1%) showed Achilles' tendon enthesitis during physical examination at the baseline study visit. Patients with Achilles enthesitis had an increase in the global VAS score, BASDAI, mBASDAI, ASDAS-CRP, and BASFI scores in comparison with patients without this feature. In addition, the mean global VAS, BASDAI, and ASDAS-CRP scores were significantly higher among patients with Achilles enthesitis over the 2 years of follow-up after adjusting for age, BMI, and current anti-TNF intake. The percentage of patients achieving ASDAS low disease activity (ASDAS < 2.1) after 2 years of follow-up was 15.9% and 31.5% for patients with and without Achilles enthesitis, respectively (p = 0.030).

CONCLUSIONS

In patients with AS, the presence of Achilles' tendon enthesitis was associated with worse scores on the outcome measures after 2 years of follow-up, leading to a lower probability of achieving low disease activity.

A clinical practice guideline for the screening and assessment of enthesitis in patients with spondyloarthritis

OBJECTIVE

The aim of this review is to provide guidance on the selection of approaches to the screening and assessment of enthesitis in patients with spondyloarthritis (SpA).

METHODS

Twenty-four questions regarding the approaches to the screening and assessment of enthesitis and the implementation details were devised, followed by a systemic literature review. The Grading of Recommendations Assessment, Development, and Evaluation methodology was employed in the development of this guideline, with modifications to evaluate non-interventional approaches under comprehensive consideration of costs, accessibility, and evidence strength. A consensus from the voting panel was required for the inclusion of the final recommendations and the strength of each recommendation.

RESULTS

Seventeen recommendations (including five strong recommendations) were included in this guideline. The voting panel expressed unequivocal support for the necessity of screening and assessment of enthesitis in patients with SpA. It was agreed unanimously that symptom evaluation and physical examination should serve as the initial steps to the recognition of enthesitis, whereas Maastricht Ankylosing Spondylitis Enthesitis Score is a reliable tool in both clinical trials and daily medical practice. Ultrasound examination is another reliable tool, with power Doppler ultrasound as an informative addition. Notwithstanding its high resolution, MRI is limited by the costs and relatively low accessibility, whereas radiographs had low sensitivity and therefore should be rendered obsolete in the assessment of enthesitis. PET/CT was strongly opposed in the detection of enthesitis.

CONCLUSION

This guideline provides clinicians with information regarding the screening and assessment of enthesitis in patients with SpA. However, this guideline does not intend on dictating choices, and the ultimate decisions should be made in light of the actual circumstances of the facilities.

The EFSUMB Guidelines and Recommendations for Musculoskeletal Ultrasound - Part I: Extraarticular Pathologies

The first part of the guidelines and recommendations for musculoskeletal ultrasound, produced under the auspices of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB), provides information about the use of musculoskeletal ultrasound for assessing extraarticular structures (muscles, tendons, entheses, ligaments, bones, bursae, fasciae, nerves, skin, subcutaneous tissues, and nails) and their pathologies. Clinical applications, practical points, limitations, and artifacts are described and discussed for every structure. After an extensive literature review, the recommendations have been developed according to the Oxford Centre for Evidence-based Medicine and GRADE criteria and the consensus level was established through a Delphi process. The document is intended to guide clinical users in their daily practice.

A Narrative Review of the Design of Ultrasound Indices for Detecting Enthesitis

With the increased utilization of musculoskeletal ultrasound in clinical practice, there has been rapid proliferation of publications on sonographic evaluation of enthesitis. This has led to the development of multiple new approaches to scoring sonographic findings in the detection of enthesitis, with variations including entheseal sites and sonographic features that limit cross-study comparisons. Furthermore, despite efforts to standardize the definition of enthesitis, there is still heterogeneity in the sonographic features included in existing ultrasound scores, and additional adjustments are required to distinguish active inflammatory changes from non-inflammatory conditions and to adjust for demographic features associated with increased prevalence of abnormal sonographic findings. This review provides an update on the current landscape of ultrasound scoring systems for enthesitis and emphasizes the importance of future data-based ultrasound scoring systems to improve the distinction between inflammatory and non-inflammatory or degenerative changes of the enthesis.

Hidden in plain sight: Is there a crucial role for enthesitis assessment in the treatment and monitoring of axial spondyloarthritis?

OBJECTIVE

To review the evidence surrounding the pathophysiology of enthesitis in axial spondyloarthritis (axSpA), its prevalence and contribution to the overall disease burden, and response to treatment at axial and peripheral sites.

METHODS

Literature searches of the Cochrane Library, PubMed, and Embase / Medline using the terms "enthesitis", "enthesopathy", "spondyloarthritis", "axial spondyloarthritis", and "ankylosing spondylitis" were conducted. Publications mentioning enthesitis or enthesopathy in the context of pathophysiology, diagnosis, or treatment were included.

RESULTS

Enthesitis is a common symptom of axSpA, occurring with high prevalence at axial and several peripheral sites. Inflammation at the site of enthesis is an early key manifestation of axSpA. Clinically evaluable enthesitis contributes significantly to the burden of disease, correlating with worse symptomatology and downstream structural damage. Despite its importance in driving axSpA disease processes, enthesitis is somewhat neglected in current approaches to disease assessment and management. Enthesitis is excluded from some commonly used disease activity measures, is not routinely assessed in clinical practice, and many methods of clinical assessment omit key accessible axial sites, such as the spinous processes.

CONCLUSION

Enthesitis plays a central role in driving the pathophysiology of axSpA. There is a need for a renewed focus on the early detection, measurement and treatment of enthesitis.

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.

Peripheral Enthesitis Detected by Ultrasonography in Patients With Axial Spondyloarthritis-Anatomical Distribution, Morphology, and Response to Tumor Necrosis Factor-Inhibitor Therapy

Objectives: To investigate the anatomical distribution, morphological abnormalities and response to adalimumab therapy of ultrasound(US)-detected peripheral enthesitis in patients with axial spondyloarthritis (SpA).

Methods: In a randomized, placebo-controlled, double-blinded, investigator-initiated trial (NCT01029847), patients with axial SpA according to the Assessment of Spondyloarthritis International Society criteria were randomized to subcutaneous adalimumab 40 mg every other week or placebo from baseline to week 6. From week 6 to 24, all patients received adalimumab 40 mg every other week. Of 49 patients enrolled, 21 patients participated in our observational US sub-study. US assessment applying the OMERACT US definitions for enthesitis of 10 peripheral entheseal regions of the upper and lower extremities and clinical examination were performed at baseline, weeks 6 and 24. US was performed by one experienced investigator. Hypo-echogenicity, increased thickness and Doppler activity of the enthesis were considered signs of active inflammation, whereas insertional bone erosions, intratendinous calcifications, and enthesophytes were regarded as signs of structural lesions.

Results: Enthesitis on US was mostly present in the lower limbs, especially in the Achilles tendon (81%), the quadriceps tendon (62%), and the greater femoral trochanter (52%). Structural lesions were predominant (38 vs. 12% of examined entheses with inflammatory changes), particularly in the entheses of the lower limbs, and exhibited no change during treatment.

Conclusion: US-detected structural lesions were common while inflammatory lesions were relatively rare in patients initiating adalimumab due to axial SpA. Structural lesions did not appear to change during 24 weeks follow-up, suggesting that these lesions may not be helpful outcome measures in short-term clinical trials.

Strain Ultrasound Elastography in the Achilles Tendon of Ankylosing Spondylitis Patients Treated With Anti-TNF-α: A Preliminary Study

BACKGROUND/AIM

To compare patients affected by ankylosing spondylitis (AS) treated with anti-TNF-α for two years with controls in terms of Achilles tendon stiffness, ultrasound structure and thickness.

PATIENTS AND METHODS

B-mode ultrasound evaluation and strain ultrasound elastography were performed in longitudinal and transverse planes on 22 Achilles tendons of 11 AS patients and 26 of 13 controls.

RESULTS

There were no significant differences in thickness and stiffness of the Achilles tendon between AS patients and controls, except for an increased thickness in the middle third of the tendon in the AS patients (p=0.04). The Achilles tendon stiffness ratio of AS patients was 1.02±0.36 vs. 1.14±0.38 in the controls (p=0.2).

CONCLUSION

AS patients had an Achilles tendon thickness greater than controls at the middle third, but no difference in the stiffness was found among them. Strain ultrasound elastography may be useful to exclude early changes in mechanical properties of tendons.

Association of Physical Activity and Medication with Enthesitis on Ultrasound in Psoriatic Arthritis

OBJECTIVE

Enthesitis is a manifestation of psoriatic arthritis (PsA), but its symptoms are difficult to interpret clinically. We investigated the associations of ultrasonographic changes in entheses with clinical characteristics in patients with PsA, and compared enthesis changes of patients aged 35 to 60 years with healthy volunteers of that age.

METHODS

Consecutive patients with PsA participated in this cross-sectional study, irrespective of enthesitis complaints and age. We collected data about complaints, physical activity and activity avoidance, medication, and clinical enthesitis. Inflammatory and structural enthesis changes were scored with the modified MAdrid Sonographic Enthesitis Index (MASEI). Among all patients, associations between ultrasound (US) scores and clinical characteristics were investigated using linear regression. We compared US scores of healthy volunteers and patients with PsA aged 35-60 years using Wilcoxon rank-sum tests.

RESULTS

Eighty-four patients with PsA and 25 healthy volunteers participated. In patients with PsA, we found a small association between higher inflammatory-modified MASEI score and older age (β 0.07, 95% CI 0-0.13) and current use of biologics (β 1.56, 95% CI 0.16-2.95). Patients who reported avoiding activities had significantly lower inflammatory-modified MASEI scores (β -1.71, 95% CI -3.1 to -0.32) than those who did not. The patients with PsA aged 35-60 years (n = 50) had similar inflammatory scores as healthy volunteers but higher structural scores (median 6 vs 2; p = 0.01).

CONCLUSION

Within patients with PsA, avoiding physical activity, younger age, and not using biologics were associated with less enthesis inflammation. Patients with PsA and healthy volunteers aged 35 to 60 years displayed similar levels of inflammatory changes of the entheses, but patients had more structural damage.

Effect of metformin on ossification and inflammation of fibroblasts in ankylosing spondylitis: An in vitro study

Ankylosing spondylitis (AS) is an autoimmune disease characterized by fibroblasts ossification. However, effective drug therapy for AS is lacking. As an antidiabetic drug, metformin has demonstrated an antiosteogenic effect on osteoblasts in vitro. And it is also a kind of specific agonists for adenosine 5'-monophosphate activated protein kinase (AMPK), which is blocked in the process of AS. Given the role in antiosteogenesis and AMPK activating, metformin was investigated of its effect on fibroblasts harvested from capsular ligament of patients with femoral neck fracture and AS. Osteogenic specific makers (Alp, Bglap, Runx2, Bmp2, and Col1) in fibroblasts administered with metformin (20 μg/mL) were detected by ALP staining, alizarin red staining, qPCR, and Western blotting after 7 and 14 days of culture. Inflammation genes (il1-β and il6) and pathway (Pi3k, Akt, and Ampk) associated markers were also evaluated. Our results showed that osteogenic specific markers were greatly downregulated and ossification was effectively inhibited in AS fibroblasts after addition of metformin. Levels of inflammation markers were also decreased by metformin. Thus, metformin exerts potent effect on suppression of ossification and inflammation in AS fibroblasts via the activation of Pi3k/Akt and AMPK pathways, which may be developed as a potential agent for treatment of AS.