Evaluation of the current use of MRI to aid the diagnosis of axial spondyloarthritis in the UK: results from a freedom of information request.

AIM: To evaluate the impact of recommendations from the 2019 consensus exercise conducted by radiologists and rheumatologists on the use of magnetic resonance imaging (MRI) to investigate axial spondyloarthritis (axSpA) in clinical practice. MATERIALS AND METHODS: A freedom of information (FOI) request was used to assess the use of MRI in the diagnosis of axSpA and radiologists' awareness of the 2019 guidance across all NHS Trusts and Health Boards in the UK, including England, Scotland, Northern Ireland, and Wales. RESULTS: The FOI request was sent to 150 Trusts/Health Boards, and 93 full responses were received. Of the 93 respondents (97%), 90 reported familiarity with the term axSpA and 70/93 (75%) reported familiarity with the 2019 recommendations. Awareness of recommendations regarding specific MRI features supportive of the diagnosis of axSpA was 74/93 (80%) for the sacroiliac joints (SIJs) and 66/93 (71%) for the spine. The median wait for MRI acquisition was 2-3 months. Fifty-two of the 93 (56%) reported at least some outsourcing of axSpA MRI (33%/29% for specialist/non-specialist outsourcing respectively); 32/93 (34%) reported some scans being reported in-house by non-musculoskeletal radiologists. CONCLUSION: There have been several positive developments in the understanding and use of MRI for the diagnosis of axSpA in the UK since the 2017 survey, although substantial scope for further improvement remains. Several new challenges have also emerged, including the increase in waiting times, reliance on outsourcing, and the reporting of MRI by non-musculoskeletal radiologists.

Have Therapeutics Enhanced Our Knowledge of Axial Spondyloarthritis?

PURPOSE OF REVIEW: An overview of how the treatment landscape of axial spondyloarthritis (axSpA) has shaped our understanding of the disease. RECENT FINDINGS: Prior to the millennium, non-steroidal anti-inflammatory drugs (NSAIDs) were the only treatment for axSpA, yet only 30% of patients responded and many developed side effects. In 2003, the first biological disease-modifying drug (bDMARD) was licensed for axSpA which substantially improved outcomes in comparison to NSAIDs. In 2022, there are now several bDMARDs for axSpA; however, they too are not universally efficacious in treating axial inflammation and may have deleterious effects on extramusculoskeletal manifestations. Nevertheless, successful or not, each bDMARD gives invaluable insight into axSpA immunobiology. This review discusses how much we have learned from the use of bDMARDs in axSpA, how this has redefined our understanding of the disease, and how we might use this knowledge to develop new and better treatments for axSpA in the future.

Chest pain mimicking pulmonary embolism may be a common presentation of COVID-19 in ambulant patients without other typical features of infection.

BACKGROUND: Radiological and pathological studies in severe COVID-19 pneumonia (SARS-CoV-2) have demonstrated extensive pulmonary immunovascular thrombosis and infarction. This study investigated whether these focal changes may present with chest pain mimicking pulmonary emoblism (PE) in ambulant patients. METHODS: CTPAs from outpatients presenting with chest pain to Leeds Teaching Hospital NHS Trust 1st March to 31 May 2020 (n = 146) and 2019 (n = 85) were compared. Regions of focal ground glass opacity (GGO), consolidation and/or atelectasis (parenchymal changes) were determined, and all scans were scored using British Society for Thoracic Imaging (BSTI) criteria for COVID-19, and the 2020 cohort was offered SARS-CoV-2 antibody testing. RESULTS: Baseline demographic and clinical data were similar between groups with absence of fever, normal lymphocytes and marginally elevated CRP and D-Dimer values. Evidence of COVID-19 or parenchymal changes was observed in 32.9% (48/146) of cases in 2020 compared to 16.5% (14/85) in 2019 (P = 0.007). 11/146 (7.5%) patients met BSTI criteria for COVID-19 in 2020 compared with 0/14 in 2019 (P = 0.008). 3/39 patients tested had detectable COVID-19 antibodies (2 with parenchymal changes and 1 with normal parenchyma) however 0/6 patients whose CTPA met BSTI criteria "likely/suspicious for COVID-19" and attended antibody testing were SARS-CoV-2 antibody positive. CONCLUSIONS: 32.8% ambulatory patients with suspected PE in 2020 had parenchymal changes with 7.5% diagnosed as COVID-19 infection by imaging criteria, despite the absence of other COVID-19 symptoms. These findings suggest that localized COVID-19 pneumonitis with immunothrombosis occurs distal to the bronchiolar arteriolar circulation, causing pleural irritation and chest pain without viraemia, accounting for the lack of fever and systemic symptoms.

Risk-mitigating behaviours in people with inflammatory skin and joint disease during the COVID-19 pandemic differ by treatment type: a cross-sectional patient survey.

BACKGROUND: Registry data suggest that people with immune-mediated inflammatory diseases (IMIDs) receiving targeted systemic therapies have fewer adverse coronavirus disease 2019 (COVID-19) outcomes compared with patients receiving no systemic treatments. OBJECTIVES: We used international patient survey data to explore the hypothesis that greater risk-mitigating behaviour in those receiving targeted therapies may account, at least in part, for this observation. METHODS: Online surveys were completed by individuals with psoriasis (globally) or rheumatic and musculoskeletal diseases (RMDs) (UK only) between 4 May and 7 September 2020. We used multiple logistic regression to assess the association between treatment type and risk-mitigating behaviour, adjusting for clinical and demographic characteristics. We characterized international variation in a mixed-effects model. RESULTS: Of 3720 participants (2869 psoriasis, 851 RMDs) from 74 countries, 2262 (60·8%) reported the most stringent risk-mitigating behaviour (classified here under the umbrella term 'shielding'). A greater proportion of those receiving targeted therapies (biologics and Janus Kinase inhibitors) reported shielding compared with those receiving no systemic therapy [adjusted odds ratio (OR) 1·63, 95% confidence interval (CI) 1·35-1·97]. The association between targeted therapy and shielding was preserved when standard systemic therapy was used as the reference group (OR 1·39, 95% CI 1·23-1·56). Shielding was associated with established risk factors for severe COVID-19 [male sex (OR 1·14, 95% CI 1·05-1·24), obesity (OR 1·37, 95% CI 1·23-1·54), comorbidity burden (OR 1·43, 95% CI 1·15-1·78)], a primary indication of RMDs (OR 1·37, 95% CI 1·27-1·48) and a positive anxiety or depression screen (OR 1·57, 95% CI 1·36-1·80). Modest differences in the proportion shielding were observed across nations. CONCLUSIONS: Greater risk-mitigating behaviour among people with IMIDs receiving targeted therapies may contribute to the reported lower risk of adverse COVID-19 outcomes. The behaviour variation across treatment groups, IMIDs and nations reinforces the need for clear evidence-based patient communication on risk-mitigation strategies and may help inform updated public health guidelines as the pandemic continues.

European League Against Rheumatism (EULAR) recommendations for the management of psoriatic arthritis with pharmacological therapies: 2015 update.

BACKGROUND: Since the publication of the European League Against Rheumatism recommendations for the pharmacological treatment of psoriatic arthritis (PsA) in 2012, new evidence and new therapeutic agents have emerged. The objective was to update these recommendations. METHODS: A systematic literature review was performed regarding pharmacological treatment in PsA. Subsequently, recommendations were formulated based on the evidence and the expert opinion of the 34 Task Force members. Levels of evidence and strengths of recommendations were allocated. RESULTS: The updated recommendations comprise 5 overarching principles and 10 recommendations, covering pharmacological therapies for PsA from non-steroidal anti-inflammatory drugs (NSAIDs), to conventional synthetic (csDMARD) and biological (bDMARD) disease-modifying antirheumatic drugs, whatever their mode of action, taking articular and extra-articular manifestations of PsA into account, but focusing on musculoskeletal involvement. The overarching principles address the need for shared decision-making and treatment objectives. The recommendations address csDMARDs as an initial therapy after failure of NSAIDs and local therapy for active disease, followed, if necessary, by a bDMARD or a targeted synthetic DMARD (tsDMARD). The first bDMARD would usually be a tumour necrosis factor (TNF) inhibitor. bDMARDs targeting interleukin (IL)12/23 (ustekinumab) or IL-17 pathways (secukinumab) may be used in patients for whom TNF inhibitors are inappropriate and a tsDMARD such as a phosphodiesterase 4-inhibitor (apremilast) if bDMARDs are inappropriate. If the first bDMARD strategy fails, any other bDMARD or tsDMARD may be used. CONCLUSIONS: These recommendations provide stakeholders with an updated consensus on the pharmacological treatment of PsA and strategies to reach optimal outcomes in PsA, based on a combination of evidence and expert opinion.

Development of a health index in patients with ankylosing spondylitis (ASAS HI): final result of a global initiative based on the ICF guided by ASAS.

OBJECTIVES: The burden of disease in patients with ankylosing spondylitis (AS) can be considerable. However, no agreement has been reached among expert members of Assessment of SpondyloArthritis International Society (ASAS) to define severity of AS. Based on the International Classification of Functioning, Disability and Health (ICF), a core set of items for AS has been selected to represent the entire spectrum of possible problems in functioning. Based on this, the objective of this study was to develop a tool to quantify health in AS, the ASAS Health Index. METHODS: First, based on a literature search, experts' and patients' opinion, a large item pool covering the categories of the ICF core set was generated. In several steps this item pool was reduced based on reliability, Rasch analysis and consensus building after two cross-sectional surveys to come up with the best fitting items representing most categories of the ICF core set for AS. RESULTS: After the first survey with 1754 patients, the item pool of 251 items was reduced to 82. After selection by an expert committee, 50 items remained which were tested in a second cross-sectional survey. The results were used to reduce the number of items to a final set of 17 items. This selection showed the best reliability and fit to the Rasch model, no residual correlation, and absence of consistent differential item function and a Person Separation Index of 0.82. CONCLUSIONS: In this long sequential study, 17 items which cover most of the ICF core set were identified that showed the best representation of the health status of patients with AS. The ASAS Health Index is a linear composite measure which differs from other measures in the public domain.

Association study of genes related to bone formation and resorption and the extent of radiographic change in ankylosing spondylitis.

OBJECTIVE: To identify genetic associations with severity of radiographic damage in ankylosing spondylitis (AS). METHOD: We studied 1537 AS cases of European descent; all fulfilled the modified New York Criteria. Radiographic severity was assessed from digitised lateral radiographs of the cervical and lumbar spine using the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). A two-phase genotyping design was used. In phase 1, 498 single nucleotide polymorphisms (SNPs) were genotyped in 688 cases; these were selected to capture >90% of the common haplotypic variation in the exons, exon-intron boundaries, and 5 kb flanking DNA in the 5' and 3' UTR of 74 genes involved in anabolic or catabolic bone pathways. In phase 2, 15 SNPs exhibiting p<0.05 were genotyped in a further cohort of 830 AS cases; results were analysed both separately and in combination with the discovery phase data. Association was tested by contingency tables after separating the samples into 'mild' and 'severe' groups, defined as the bottom and top 40% by mSASSS, adjusted for gender and disease duration. RESULTS: Experiment-wise association was observed with the SNP rs8092336 (combined OR 0.32, p=1.2×10(-5)), which lies within RANK (receptor activator of NFκB), a gene involved in osteoclastogenesis, and in the interaction between T cells and dendritic cells. Association was also found with the SNP rs1236913 in PTGS1 (prostaglandin-endoperoxide synthase 1, cyclooxygenase 1), giving an OR of 0.53 (p=2.6×10(-3)). There was no observed association between radiographic severity and HLA-B*27. CONCLUSIONS: These findings support roles for bone resorption and prostaglandins pathways in the osteoproliferative changes in AS.

EULAR recommendations for the use of imaging in the diagnosis and management of spondyloarthritis in clinical practice.

A taskforce comprised of an expert group of 21 rheumatologists, radiologists and methodologists from 11 countries developed evidence-based recommendations on the use of imaging in the clinical management of both axial and peripheral spondyloarthritis (SpA). Twelve key questions on the role of imaging in SpA were generated using a process of discussion and consensus. Imaging modalities included conventional radiography, ultrasound, magnetic resonance imaging, computed tomography (CT), positron emission tomography, single photon emission CT, dual-emission x-ray absorptiometry and scintigraphy. Experts applied research evidence obtained from systematic literature reviews using MEDLINE and EMBASE to develop a set of 10 recommendations. The strength of recommendations (SOR) was assessed by taskforce members using a visual analogue scale. A total of 7550 references were identified in the search process, from which 158 studies were included in the systematic review. Ten recommendations were produced using research-based evidence and expert opinion encompassing the role of imaging in making a diagnosis of axial SpA or peripheral SpA, monitoring inflammation and damage, predicting outcome, response to treatment, and detecting spinal fractures and osteoporosis. The SOR for each recommendation was generally very high (range 8.9-9.5). These are the first recommendations which encompass the entire spectrum of SpA and evaluate the full role of all commonly used imaging modalities. We aimed to produce recommendations that are practical and valuable in daily practice for rheumatologists, radiologists and general practitioners.

The role of biomechanical factors in ankylosing spondylitis: the patient's perspective.

Biomechanical factors including occupational joint physical stressing and joint injury have been linked to spondyloarthritis. We explored such factors in ankylosing spondylitis (AS). A retrospective, online survey was developed alongside the UK National Ankylosing Spondylitis Society (NASS). Questions on early entheseal symptoms, potential precipitating trauma, sporting activity, and physiotherapy were asked. A total of 1026 patients responded with 44% recalling an instance of injury or trauma as a potential trigger for their AS. After symptom onset, 55% modified sporting activities and 28% reported that the initial AS recommended exercises exacerbated symptoms. Patients report physical trauma, exercise and physiotherapy as potential triggers for AS symptoms. These findings further support the experimental evidence for the role of biomechanical factors in disease.

Comparison of three screening tools to detect psoriatic arthritis in patients with psoriasis (CONTEST study).

BACKGROUND: Multiple questionnaires to screen for psoriatic arthritis (PsA) have been developed but the optimal screening questionnaire is unknown. OBJECTIVES: To compare three PsA screening questionnaires in a head-to-head study using CASPAR (the Classification Criteria for Psoriatic Arthritis) as the gold standard. METHODS: This study recruited from 10 U.K. secondary care dermatology clinics. Patients with a diagnosis of psoriasis, not previously diagnosed with PsA, were given all three questionnaires. All patients who were positive on any questionnaire were invited for a rheumatological assessment. Receiver operating characteristic (ROC) curves were used to compare the sensitivity, specificity and area under the curve of the three questionnaires according to CASPAR criteria. RESULTS: In total, 938 patients with psoriasis were invited to participate and 657 (70%) patients returned the questionnaires. One or more questionnaires were positive in 314 patients (48%) and 195 (62%) of these patients attended for assessment. Of these, 47 patients (24%) were diagnosed with PsA according to the CASPAR criteria. The proportion of patients with PsA increased with the number of positive questionnaires (one questionnaire, 19·1%; two, 34·0%; three, 46·8%). Sensitivities and specificities for the three questionnaires, and areas under the ROC curve were, respectively: Psoriatic Arthritis Screening Evaluation (PASE), 74·5%, 38·5%, 0·594; Psoriasis Epidemiology Screening Tool (PEST), 76·6%, 37·2%, 0·610; Toronto Psoriatic Arthritis Screen (ToPAS), 76·6%, 29·7%, 0·554. The majority of patients with a false positive response had degenerative or osteoarthritis. CONCLUSION: Although the PEST and ToPAS questionnaires performed slightly better than the PASE questionnaire at identifying PsA, there is little difference between these instruments. These screening tools identify many cases of musculoskeletal disease other than PsA.

Validation of the ASAS criteria and definition of a positive MRI of the sacroiliac joint in an inception cohort of axial spondyloarthritis followed up for 8 years.

BACKGROUND: The new Assessment of SpondyloArthritis international Society (ASAS) criteria classify axial spondyloarthritis (SpA) into human leucocyte antigen-B27 and/or imaging-based arms. To aid implementation, ASAS has proposed a definition of a positive MRI for active sacroiliitis. OBJECTIVE: The authors aimed to test the diagnostic and predictive value of the ASAS criteria and definition of a 'positive' MRI. METHODS: Baseline MRI scans on 29 patients with early inflammatory back pain and 18 controls were read independently by four experienced rheumatologists. Both arms of the criteria were tested against a 'gold standard' of physician diagnosis of SpA. MRI abnormalities were assessed according to a global assessment of MRI and the ASAS definition. Sensitivity, specificity and likelihood ratios for individual and concordant reader data were calculated for axial SpA diagnosis at baseline and the development of radiographic sacroiliitis, fulfilling the modified New York criteria at 8 years. RESULTS: All patients were classified as having axial SpA, with more patients fulfilling the imaging arm (83%, n=24/29) than the human leucocyte antigen B27 arm (62%, n=18/29). Concordant reader data showed that the baseline MRI had high diagnostic utility for SpA according to global assessment (sensitivity/specificity: 66%/94%, LR+ (positive likelihood ratio) 11.8, LR- (negative likelihood ratio) 0.4) and ASAS definition (sensitivity/specificity: 79%/89%, LR+ 7.1, LR- 0.2). Likewise, a positive baseline MRI had 100% sensitivity for subsequent radiographic sacroiliitis by either assessment, although specificity was lower (56% for global assessment and 33% for ASAS definition). CONCLUSION: Both arms of the ASAS criteria have good diagnostic utility in early SpA, although they are of limited value for the prediction of radiographic progression. This may be due to the definition of a positive MRI for sacroiliitis that lacks specificity at baseline.

European League Against Rheumatism recommendations for the management of psoriatic arthritis with pharmacological therapies.

BACKGROUND: Psoriatic arthritis (PsA) is a clinically heterogeneous disease. Clear consensual treatment guidance focused on the musculoskeletal manifestations of PsA would be advantageous. The authors present European League Against Rheumatism (EULAR) recommendations for the treatment of PsA with systemic or local (non-topical) symptomatic and disease-modifying antirheumatic drugs (DMARD). METHODS: The recommendations are based on evidence from systematic literature reviews performed for non-steroidal anti-inflammatory drugs (NSAID), glucocorticoids, synthetic DMARD and biological DMARD. This evidence was discussed, summarised and recommendations were formulated by a task force comprising 35 representatives, and providing levels of evidence, strength of recommendations and levels of agreement. RESULTS: Ten recommendations were developed for treatment from NSAID through synthetic DMARD to biological agents, accounting for articular and extra-articular manifestations of PsA. Five overarching principles and a research agenda were defined. CONCLUSION: These recommendations are intended to provide rheumatologists, patients and other stakeholders with a consensus on the pharmacological treatment of PsA and strategies to reach optimal outcomes, based on combining evidence and expert opinion. The research agenda informs directions within EULAR and other communities interested in PsA.

Imaging of the Achilles tendon in spondyloarthritis: a comparison of ultrasound and conventional, short and ultrashort echo time MRI with and without intravenous contrast.

OBJECTIVES: To compare conventional MRI, ultrashort echo time MRI and ultrasound for assessing the extent of tendon abnormalities in spondyloarthritis. METHODS: 25 patients with spondyloarthritis and Achilles symptoms were studied with MRI and ultrasound. MR images of the Achilles tendon were acquired using T1-weighted spin echo, gradient echo and ultrashort echo time (UTE) sequences with echo times (TE) between 0.07 and 16 ms, before and after intravenous contrast medium. Greyscale and power Doppler ultrasound were also performed. The craniocaudal extent of imaging abnormalities measured by a consultant musculoskeletal radiologist was compared between the different techniques. RESULTS: Abnormalities were most extensive on spoiled gradient echo images with TE = 2 ms. Contrast enhancement after intravenous gadolinium was greatest on the UTE images (TE = 0.07 ms). Fewer abnormalities were demonstrated using unenhanced UTE. Abnormalities were more extensive on MRI than ultrasound. Contrast enhancement was more extensive than power Doppler signal. CONCLUSIONS: 3D spoiled gradient echo images with an echo time of 2 ms demonstrate more extensive tendon abnormalities than the other techniques in spondyloarthritis. Abnormalities of vascularity are best demonstrated on enhanced ultrashort echo time images.

Bone loss in very early inflammatory back pain in undifferentiated spondyloarthropathy: a 1-year observational study.

OBJECTIVE: Bone loss in patients with inflammatory back pain (IBP) suspicious of early undifferentiated spondyloarthropathy is poorly defined. The aim of this study was to examine changes in bone mineral density (BMD) at the hip, lumbar spine and hand in patients with early IBP and to look for possible biomarkers associated with this change. METHODS: In 30 patients with early IBP, clinical data were collected and BMD assessed using dual energy x-ray absorptiometry at baseline, 6 and 12 months. Further imaging performed included MRI of the sacroiliac joints (SIJs) and spine at baseline and x-rays of the SIJs at baseline and after 8 years. RESULTS: After 12 months no significant reduction in hip, spine and hand BMD was seen at the group level. However, hip bone loss was found to be associated with raised baseline C-reactive protein levels, baseline MRI bone marrow oedema of the SIJs and the presence of radiographic sacroiliitis after 8 years. No association was found with change in spine and hand BMD. CONCLUSION: Systemic bone loss in the hip is an early feature of the inflammatory disease process in patients with IBP in undifferentiated spondyloarthropathy and is related to disease activity. These data highlight the importance of aggressive intervention in the early stages of disease in undifferentiated spondyloarthropathy.

The fatty Romanus lesion: a non-inflammatory spinal MRI lesion specific for axial spondyloarthropathy.

BACKGROUND: Fatty changes at vertebral corners have been reported on MRI in ankylosing spondylitis but the distribution or specificity of these lesions to early axial spondyloarthropathy (axial-SpA) has not been determined. OBJECTIVE: To assess the diagnostic utility of fatty Romanus lesions (FRLs) for axial-SpA in a population with chronic back pain. METHODS: Axial-skeleton TI SE and fat-suppressed MRI were performed on 174 patients with back pain and 11 controls. MRI lesions including FRLs were scored blind. An imaging diagnosis was given on MRI findings alone and compared with the 'gold standard' treating doctor's diagnosis. RESULTS: Twenty-nine patients had FRLs: 31% (20/64) of patients with spondyloarthropathy, 13% (6/45) with degenerative arthritis, 4% (2/45) with spinal malignancy, 5% (1/20) with 'other' diagnoses; none of 11 normal subjects had FRLs. The majority of the FRLs in SpA 60% (135/226) were present in the thoracic spine. The diagnostic utility of FRLs for SpA (likelihood ratio (LR) = 4.7) was significantly (p<0.05) greater than for other diagnoses and increased further (LR = 12.6, p<0.05) when more than five FRLs were present. Of note 5/20 (25%) patients with SpA with FRLs had no diagnostic bone-oedema lesions on fat-suppressed MRI, suggesting that FRLs may be useful diagnostically in axial-SpA. CONCLUSION: This study defines the FRL as a diagnostic imaging feature of axial-SpA, which may be useful where inflammatory changes are absent on fat-suppression MRI and where radiography is normal.

Baseline and 1-year magnetic resonance imaging of the sacroiliac joint and lumbar spine in very early inflammatory back pain. Relationship between symptoms, HLA-B27 and disease extent and persistence.

BACKGROUND: The precise anatomical location of pathology associated with inflammatory back pain (IBP) in early spondyloarthropathy (SpA) remains unclear. OBJECTIVE: To use MRI to study the sacroiliac joint (SIJ) and lumbar spine (LS) and explore the relationship between sites and extent of inflammation and HLA-B27 status over 12 months. METHODS: 54 patients with IBP; median duration 24 weeks (54% HLA-B27 positive; median Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) 5.65) and 22 control subjects (11 with mechanical back pain; 11 volunteers) were recruited and 63% (n = 34) were reassessed at 1 year. Fat saturation and T1-weighted MRI was performed with images being scored for active bone marrow oedema (BMO) lesions representative of inflammation. RESULTS: At baseline 46/54 (85%) patients had BMO (SIJs and LS) compared with 40% in the control group. The majority of affected patients had inflammation at the SIJ level (96% (n = 44); 23.5% (n = 12) LS) and 28.3% (n = 13) at both sites simultaneously. The SIJ activity score confirmed more severe inflammation (BMO grade 2 or 3: 52.2%) in the IBP group (controls = BMO grade 1: 100%; p<0.001). HLA-B27 was associated with both the severity (p = 0.009) and number of baseline SIJ lesions (p = 0.045) and with persistence (SIJ or LS) at 1 year (p = 0.02). 90% of reattenders fulfilled European Spondyloarthropathy Study Group criteria; 73.5% showed MRI inflammation despite clinical improvement (median BASDAI 5.65 to 3.05; p<0.009). CONCLUSION: LS and SIJ involvement may occur simultaneously in very early SpA and may be differentiated from non-inflammatory back pain by the severity of MRI lesions. HLA-B27 is associated with both the severity of osteitis and its persistence.

MRI and clinical findings in patients with ankylosing spondylitis eligible for anti-tumour necrosis factor therapy after a short course of etoricoxib.

OBJECTIVE: To describe and assess the response to short-term etoricoxib as shown by MRI and clinical variables in patients with ankylosing spondylitis (AS) selected for eligibility for anti-tumour necrosis factor therapy. METHODS: In a 6-week open-label study, 22 patients with AS and eligible for biological therapy were treated with 90 mg of etoricoxib daily. Clinical and laboratory parameters were obtained and MRI of the sacroiliac joints and the lower thoracic and lumbar spine performed at baseline and at week 6. The primary end point was the proportion of patients fulfilling the SpondyloArthritis international Society (ASAS) response criteria for biological therapies (ASASBIO) while secondary end points included the change in MRI-determined bone lesions. RESULTS: Eight of 20 completers improved enough to meet the ASASBIO response criteria and most clinical variables improved significantly. Fifteen patients had a total of 63 MRI-detectable lesions; overall, 13/60 lesions with paired scans either resolved completely or improved, while five lesions worsened or appeared during treatment. CONCLUSION: Etoricoxib is an effective symptomatic treatment for patients with AS; however, its effect on MRI-detected lesions is small. Further studies are needed to determine the effect of etoricoxib on MRI-determined bone oedema.