Axial involvement in patients with early peripheral spondyloarthritis: a prospective MRI study of sacroiliac joints and spine

ASAS consensus definition of early axial spondyloarthritis

OBJECTIVES

To develop a consensual definition for the term 'early axial spondyloarthritis-axSpA'-and 'early peripheral spondyloarthritis-pSpA'.

METHODS

The ASAS (Assessment of SpondyloArthritis international Society-Spondyloarthritis EARly definition) steering committee convened an international working group (WG). Five consecutive steps were followed: (1) systematic literature review (SLR); (2) discussion of SLR results within the WG and ASAS community; (3) a three-round Delphi survey inviting all ASAS members to select the items that should be considered for the definition; (4) presentation of Delphi results to the WG and ASAS community and (5) ASAS voting and endorsement (2023 annual meeting).

RESULTS

Following the SLR, consensus was to proceed with an expert-based definition for early axSpA (81% in favour) but not for pSpA (54% against). Importantly, early axSpA should be based on symptom duration taking solely axial symptoms into account. 151-164 ASAS members participated in the Delphi surveys. Consensus was achieved for considering the following items within early axSpA definition: duration of symptoms ≤2 years; axial symptoms defined as cervical/thoracic/back/buttock pain or morning stiffness; regardless of the presence/absence of radiographic damage. The WG agreed that in patients with a diagnosis of axSpA 'early axSpA' should be defined as a duration of ≤2 years of axial symptoms. Axial symptoms should include spinal/buttock pain or morning stiffness and should be considered by a rheumatologist as related to axSpA. The ASAS community endorsed this proposal (88% in favour).

CONCLUSIONS

Early axSpA has newly been defined, based on expert consensus. This ASAS definition should be adopted in research studies addressing early axSpA.

Advances in the Evaluation of Peripheral Enthesitis by Magnetic Resonance Imaging in Patients With Psoriatic Arthritis

Enthesitis is a key disease manifestation in patients with psoriatic arthritis (PsA) that considerably contributes to pain, lower physical function, and reduced quality of life. Clinical assessment of enthesitis lacks sensitivity and specificity, and therefore better methods are urgently needed. Magnetic resonance imaging (MRI) allows detailed assessment of the components of enthesitis, and consensus-based validated MRI scoring systems exist. These include the Outcome Measures in Rheumatology (OMERACT) Heel Enthesitis MRI Scoring System (HEMRIS) method, which assesses the entheses of the heel region in a detailed manner, and the OMERACT MRI Whole-Body Score for Inflammation in Peripheral Joints and Entheses (MRI-WIPE) method, which provides an overall assessment of the inflammatory burden in the peripheral entheses and joints in the entire body using whole-body MRI. At an MRI workshop at the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) 2022 meeting in Brooklyn, the MRI appearances of peripheral enthesitis were described, as were the scoring methods. The utility of MRI for improved assessment of enthesitis was demonstrated with examples of patient cases. Clinical trials in PsA that evaluate enthesitis by MRI as a key endpoint should include the presence of MRI enthesitis as an inclusion criterion, and apply validated MRI outcomes to assess the effect of therapeutics on enthesitis are recommended.

A mixed methods study to uncover impediments to accurate diagnosis of nonradiographic axial spondyloarthritis in the USA

INTRODUCTION/OBJECTIVES

Delayed diagnosis of axial spondyloarthritis (axSpA) is well documented; little is known about the diagnostic journey and impediments for US patients with nonradiographic axSpA (nr-axSpA). It is hypothesized that impediments are varied and exist at both the healthcare provider (HCP) and patient levels. This study aims to understand patient experiences and contributors to delayed nr-axSpA diagnosis in the USA.

METHOD

Interviews of adults with rheumatologist-diagnosed nr-axSpA, recruited through Spondylitis Association of America outreach and patient panels, and of rheumatologists, explored the diagnostic journey and diagnostic barriers. Emerging themes were further explored in an online patient survey. A multiple logistic regression analysis evaluated the main outcome variable, factors affecting time to nr-axSpA diagnosis.

RESULTS

Interviews were conducted with 25 patients and 16 rheumatologists. Survey responses from 186 eligible patients revealed median time from symptom onset to diagnosis of nr-axSpA was 3.25 years. Delayed diagnosis was significantly more likely for women and people in rural areas. Most patients consulted ≥4 different types of HCPs before a rheumatologist and ≥2 rheumatologists before diagnosis. Impediments to timely diagnosis included insidious chronic pain; episodic symptom patterns attributed to activity; symptoms other than chronic lumbosacral back pain requiring medical consultation; and unfamiliarity with and misperceptions about nr-axSpA among HCPs, radiologists, and rheumatologists.

CONCLUSIONS

Delayed nr-axSpA diagnosis is common and reflects HCP knowledge gaps and frequent patient presentation with dominant nonaxial symptoms. Targeted HCP education, research into early disease patterns, and interventions sensitive to the broader spectrum of nr-axSpA manifestations are needed to improve timely diagnosis. Key Points • Patients with nr-axSpA often see multiple types of HCPs, and multiple rheumatologists, before receiving a diagnosis. • Both patients and HCPs are unfamiliar with nr-axSpA and its symptoms, lacking understanding that nr-axSpA can occur in young people, females, and those presenting with normal x-rays. • Disease recognition by nonrheumatology HCPs is key for early referral. • Education on cardinal features, epidemiology, burden, and benefits of timely nr-axSpA diagnosis is warranted for HCPs who commonly manage back pain.

MRI in axial spondyloarthritis: understanding an 'ASAS-positive MRI' and the ASAS classification criteria

In 2009, the Assessment of SpondyloArthritis international Society (ASAS) published a definition of 'active sacroiliitis on magnetic resonance imaging (MRI) for classification of axial spondyloarthritis'. This new definition of an 'ASAS-positive MRI' was integral to new classification criteria for axial spondyloarthritis that were published in the same year. The ASAS MRI definition had the considerable advantage of simplicity and the definition gained popularity as guidance for interpreting MRI of the sacroiliac joints in clinical practice. However, classification criteria are not designed for use in clinical practice with the consequence that overreliance on the presence of bone marrow edema, which is the principal determinant of an 'ASAS-positive MRI', may result in a tendency to overcall inflammatory sacroiliitis in the clinical setting. This article aims to inform the reader about the rationale behind the ASAS definition of a positive MRI and ASAS classification criteria, their proper use in research and why they should not be used in clinical practice. The article also contains guidance for an updated imaging protocol and interpretation of images including typical imaging findings, differential diagnosis, and common pitfalls.

Australian Consensus Statements for the Assessment and Management of Non-radiographic Axial Spondyloarthritis

Background

The understanding of non-radiographic axial spondyloarthritis (nr-axSpA) has accelerated over the last decade, producing a number of practice-changing developments. Diagnosis is challenging. No diagnostic criteria exist, no single finding is diagnostic, and other causes of back pain may act as confounders.

Aim

To update and expand the 2014 consensus statement on the investigation and management of non‐radiographic axial spondyloarthritis (nr-axSpA).

Methods

We created search questions based on our previous statements and four new topics then searched the MEDLINE and Cochrane databases. We assessed relevant publications by full-text review and rated their level of evidence using the GRADE system. We compiled a GRADE evidence summary then produced and voted on consensus statements.

Results

We identified 5145 relevant publications, full-text reviewed 504, and included 176 in the evidence summary. We developed and voted on 22 consensus statements. All had high agreement. Diagnosis of nr-axSpA should be made by experienced clinicians, considering clinical features of spondyloarthritis, blood tests, and imaging. History and examination should also assess alternative causes of back pain and related conditions including non-specific back pain and fibromyalgia. Initial investigations should include CRP, HLA-B27, and AP pelvic radiography. Further imaging by T1 and STIR MRI of the sacroiliac joints is useful if radiography does not show definite changes. MRI provides moderate-to-high sensitivity and high specificity for nr-axSpA. Acute signs of sacroiliitis on MRI are not specific and have been observed in the absence of spondyloarthritis. Initial management should involve NSAIDs and a regular exercise program, while TNF and IL-17 inhibitors can be used for high disease activity unresponsive to these interventions. Goals of treatment include improving the frequent impairment of social and occupational function that occurs in nr-axSpA.

Conclusions

We provide 22 evidence-based consensus statements to provide practical guidance in the assessment and management of nr-axSpA.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-021-00416-7.

Beyond the sacro-Iliac joints: Vertebral involvement in axial spondylarthritis

Imaging plays a central role in the diagnosis of axial spondylarthritis (axSpA). Commonly the sacroiliac joints are involved but vertebral involvement can occur in isolation in 1 out of 4 patients. Recognizing vertebral involvement patterns in axSpA can help establishing a diagnosis early and initiate therapy before irreversible changes have occurred. Magnetic resonance imaging (MRI) is considered the reference standard for early detection of inflammatory changes of the disease. Aims of this review are to present an overview of the imaging findings of vertebral involvement in axSpA, and to detail the current recommendations on the role of imaging in the diagnosis of axSpA in patients with isolated vertebral involvement.

Method for Diagnosing the Bone Marrow Edema of Sacroiliac Joint in Patients with Axial Spondyloarthritis Using Magnetic Resonance Image Analysis Based on Deep Learning

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease of the sacroiliac joints. In this study, we develop a method for detecting bone marrow edema by magnetic resonance (MR) imaging of the sacroiliac joints and a deep-learning network. A total of 815 MR images of the sacroiliac joints were obtained from 60 patients diagnosed with axSpA and 19 healthy subjects. Gadolinium-enhanced fat-suppressed T1-weighted oblique coronal images were used for deep learning. Active sacroiliitis was defined as bone marrow edema, and the following processes were performed: setting the region of interest (ROI) and normalizing it to a size suitable for input to a deep-learning network, determining bone marrow edema using a convolutional-neural-network-based deep-learning network for individual MR images, and determining sacroiliac arthritis in subject examinations based on the classification results of individual MR images. About 70% of the patients and normal subjects were randomly selected for the training dataset, and the remaining 30% formed the test dataset. This process was repeated five times to calculate the average classification rate of the five-fold sets. The gradient-weighted class activation mapping method was used to validate the classification results. In the performance analysis of the ResNet18-based classification network for individual MR images, use of the ROI showed excellent detection performance of bone marrow edema with 93.55 ± 2.19% accuracy, 92.87 ± 1.27% recall, and 94.69 ± 3.03% precision. The overall performance was additionally improved using a median filter to reflect the context information. Finally, active sacroiliitis was diagnosed in individual subjects with 96.06 ± 2.83% accuracy, 100% recall, and 94.84 ± 3.73% precision. This is a pilot study to diagnose bone marrow edema by deep learning based on MR images, and the results suggest that MR analysis using deep learning can be a useful complementary means for clinicians to diagnose bone marrow edema.

The value of magnetic resonance imaging for assessing disease extent and prediction of relapse in early peripheral spondyloarthritis

OBJECTIVE

We aimed to assess the inflammatory burden in pSpA by lower-extremity MRI in an early remission-induction strategy study with TNF blockade. Furthermore, we sought to determine the value of MRI to predict disease relapse versus sustained remission after treatment discontinuation.

METHODS

Thirty-two early pSpA patients with lower limb involvement on clinical examination and confirmed by ultrasonography, participated in a remission-induction trial with a TNF-inhibitor (TNFi). Patients underwent MRI of joints and entheses of the lower extremities at baseline and at clinical remission, after which TNFi treatment was withdrawn. Images were evaluated for joint effusion, joint osteitis, entheseal soft tissue inflammation (STI), and entheseal osteitis.

RESULTS

Joint effusion and enthesitis on clinical examination and ultrasonography correlated well with MRI abnormalities. In addition, a substantial amount of subclinical involvement was seen on MRI, mainly in ankle joints and heel entheses. Inflammation scores were markedly lower in the subclinical joints and entheses versus those clinically involved. Inflammatory load on MRI decreased significantly upon TNFi treatment. Whereas 80% of the clinically involved joints at baseline showed no effusion on remission MRI, two out of three involved entheses at baseline showed residual inflammation. In addition, patients relapsing after treatment discontinuation displayed more entheseal STI on remission MRI compared to those maintaining drug-free remission.

CONCLUSION

Our findings delineate a differential response of synovitis and enthesitis, with enthesitis on MRI responding less upon TNFi treatment. Furthermore, residual entheseal inflammation might be indicative for the need for continuous therapy.

Unveiling axial involvement in psoriatic arthritis: An ancillary analysis of the ASAS-perSpA study

OBJECTIVE

To determine the clinical profile of axial psoriatic arthritis (PsA) in a worldwide setting. Secondly, to identify factors associated with the development of axial involvement in patients with PsA.

METHODS

Data from 3684 patients with axial spondyloarthritis (axSpA) or PsA from the ASAS-perSpA study were analysed. The ASAS-perSpA is a cross-sectional study that recruited consecutive patients with SpA (as diagnosed by their rheumatologist) from 68 centers worldwide and collected patient and disease data. First, 2651 axSpA patients and 367 PsA patients with any history of axial involvement (axPsA) were compared using logistic regression to later identify predictive factors for rheumatologist diagnosis of axPsA. Secondly, 367 axPsA patients were compared with 666 PsA patients lacking axial involvement (peripheral PsA [pPsA]) and the characteristics associated with axial manifestations were explored by logistic regression analysis.

RESULTS

Patients with axPsA were older and less frequently males or HLA*B27 positive in comparison with axSpA patients. Additionally, while patients with axPsA had more peripheral manifestations and psoriasis, other extra-musculoskeletal manifestations (IBD and uveitis) were more frequent in those with axSpA. In the multivariable analysis, older age at diagnosis (OR = 1.04), peripheral arthritis (OR = 7.32) and dactylitis (OR = 2.82) were significantly associated with the diagnosis of axPsA. However, uveitis (OR = 0.22), IBD (OR = 0.12), HLA*B27 carriership (OR = 0.26) or sacroiliitis on imaging (OR = 0.5) were inversely associated with axPsA diagnosis as compared to axSpA. Axial involvement in patients with PsA was significantly associated with male gender (OR = 1.68), elevated CRP (OR = 2.87) and the absence of psoriasis (OR = 0.33).

CONCLUSION

In this worldwide setting axPsA was defined by rheumatologists as a unique phenotype, with disease features lying between axSpA and pure pPsA.