Comparison of established and preliminarily proposed ASAS MRI working group cut-offs for inflammatory MRI lesions in the sacroiliac joints in radiographic and non-radiographic axial spondyloarthritis.

BACKGROUND: A consensus definition for active sacroiliitis by MRI, mentioned in the Assessment of SpondyloArthritis International Society (ASAS) classification criteria for axial spondyloarthritis (axSpA), was published in 2009 and included a qualitative and quantitative MRI cut-off component. In 2021, updates to the quantitative component were preliminarily proposed. This post hoc analysis of part A of the phase 3 open-label C-OPTIMISE study (NCT02505542) explores the differences by applying the 2009 and preliminary 2021 inflammatory cut-offs on clinical outcomes of axSpA patients treated with certolizumab pegol. METHODS: Baseline MRI scans were used to classify 657 patients as MRI+ or MRI- according to the quantitative components of the 2009 and preliminary 2021 MRI cut-offs for inflammatory lesions. Clinical outcomes, including ASAS ≥40% improvement (ASAS40), Ankylosing Spondylitis Disease Activity Score and Bath Ankylosing Spondylitis Disease Activity Index, were reported to week 48. RESULTS: Across all analysed outcomes, 2009 MRI+ and preliminary 2021 MRI+ subgroups showed similar results. Notably, clinical outcomes for the discordant group (2009 MRI+but preliminary 2021 MRI- group; 53/657 [8.1%]) were close to those seen in MRI- patients according to either 2009 or preliminary 2021 inflammatory cut-offs, and notably different from the totality of MRI+ subgroups. CONCLUSION: This analysis suggests that the preliminary 2021 cut-offs for MRI inflammatory lesions may slightly increase the specificity of the quantitative part of the 2009 MRI inflammatory lesion definition. The effects of the updated MRI cut-offs need to be assessed on the basis of efficacy outcomes and with the inclusion of aspects of structural changes. TRIAL REGISTRATION NUMBER: NCT02505542.

Bone marrow edema detection for diagnostic support of axial spondyloarthritis using MRI.

PURPOSE: This study proposes a process for detecting slices with bone marrow edema (BME), a typical finding of axSpA, using MRI scans as the input. This process does not require manual input of ROIs and provides the results of the judgment of the presence or absence of BME on a slice and the location of edema as the rationale for the judgment. METHODS: First, the signal intensity of the MRI scans of the sacroiliac joint was normalized to reduce the variation in signal values between scans. Next, slices containing synovial joints were extracted using a slice selection network. Finally, the BME slice detection network determines the presence or absence of the BME in each slice and outputs the location of the BME. RESULTS: The proposed method was applied to 86 MRI scans collected from 15 hospitals in Japan. The results showed that the average absolute error of the slice selection process was 1.49 slices for the misalignment between the upper and lower slices of the synovial joint range. The accuracy, sensitivity, and specificity of the BME slice detection network were 0.905, 0.532, and 0.974, respectively. CONCLUSION: This paper proposes a process to detect the slice with BME and its location as the rationale of the judgment from an MRI scan and shows its effectiveness using 86 MRI scans. In the future, we plan to develop a process for detecting other findings such as bone erosion from MR scans, followed by the development of a diagnostic support system.

Exploratory analysis of the potential disconnect between objective inflammatory response and clinical response following certolizumab pegol treatment in patients with active axial spondyloarthritis.

INTRODUCTION: This post hoc analysis evaluated the relationship between objective measures of inflammation and clinical outcomes following 12 weeks of certolizumab pegol (CZP) treatment in patients with active axial spondyloarthritis (axSpA). METHODS: We report the proportion of patients achieving ≥50% and ≥75% improvements in clinical composite outcome measures of disease activity (Axial Spondyloarthritis Disease Activity Score [ASDAS], Bath Ankylosing Spondylitis Disease Activity Index [BASDAI]) and objective measures of inflammation (C reactive protein [CRP], Ankylosing Spondylitis spine MRI score [ASspiMRI-a] Berlin score and Spondyloarthritis Research Consortium of Canada [SPARCC] MRI Sacroiliac Joints [SIJ] score) following 12 weeks of CZP treatment. Data from two independent readers over four MRI reading campaigns were pooled using a mixed model with repeated measures for each variable. RESULTS: 136 patients (radiographic axSpA [r-axSpA]: 76; non-radiographic axSpA [nr-axSpA]: 60) were included. Following CZP treatment, CRP, ASspiMRI-a Berlin score and SPARCC SIJ score were reduced by ≥50% in most patients (CRP: 136/136 [100.0%]; Berlin: 73/136 [53.7%]; SPARCC SIJ: 71/136 [52.2%]), and often by ≥75%. Less than half of patients with r-axSpA and nr-axSpA showed ≥50% reduction in clinical responses (BASDAI: 64/136 [47.1%]; ASDAS: 66/136 [48.5%]). These results were also observed at the individual patient level; ≥50% improvements in MRI/CRP inflammatory measures did not translate into similar improvements in clinical responses for most patients. CONCLUSION: There is a potential disconnect between objective measures of inflammation and clinical outcome responses in patients with axSpA. The use of only clinical response measures as trial endpoints may underestimate anti-inflammatory treatment effects. TRIAL REGISTRATION NUMBER: NCT01087762.

Diagnosis challenges in inception cohorts in axial spondyloarthritis: the case of the French national DESIR cohort.

BACKGROUND: Inception cohorts aim to describe chronic diseases from diagnosis and over years of follow-up. Axial spondyloarthritis (axSpA) diagnosis might be challenging during the first years of the disease. Thus, identifying the features that will be associated with a confirmed diagnosis over time is key. OBJECTIVES: To assess the frequency and the predisposing factors for a change of an initial diagnosis in an inception axSpA cohort. METHODS: DESIR is an ongoing national multicentre inception axSpA cohort with currently 12.5 years of follow-up. At the entry visit and confirmed at each visit, the diagnosis of axSpA was based on the opinion of the treating rheumatologist. Follow-up was interrupted in case of a change in this initial diagnosis. Multiple imputation was used to estimate the probability of a change in the initial diagnosis of axSpA for each patient lost to follow-up. Factors predisposing to an unchanged diagnosis of axSpA were then assessed using a multivariate logistic regression model on the imputed data sets. RESULTS: Of the 708 patients included, over 10 years of follow-up, 45 (6.4%) were excluded due to a diagnosis change and 300 (42.4%) patients were lost to follow-up. Based on the imputation of these 300 patients, a change in their initial axSpA diagnosis was estimated in 42 (14.0%). Factors predisposing to an unchanged initial axSpA diagnosis during follow-up were (ORs (95% CIs)): radiographic sacroiliitis: 17.0 (4.1 to 71.0); psoriasis: 5.3 (2.0 to 14.3); CRP≥6 mg/L: 2.7 (1.3 to 5.3); good NSAID response: 2.5 (1.5 to 4.2); HLA B27+: 2.0 (1.3 to 3.3); anterior chest wall pain: 2.0 (1.2 to 3.3) and female sex: 1.9 (1.2 to 3.0). CONCLUSION: These data suggest that a change in diagnosis in recent onset axSpA exists, but is not frequent, and is less likely to occur in the presence of objective features at baseline.

Sensitivity to change of structural outcomes in axial spondyloarthritis after 10 years of follow up. Data from the DESIR cohort.

OBJECTIVE: To evaluate the sensitivity to change in structural imaging outcomes over 10 years of follow-up in patients with axial spondyloarthritis (axSpA). METHODS: Patients with axSpA from the Devenir des Spondyloarthropathies Indifferénciées Récentes cohort were included. Radiographs and MRIs of the sacroiliac joints (SIJ) and spine were obtained at baseline and at 1, 2, 5 and 10 years. The yearly rate of change of each structural outcome was analysed using generalised estimating equation models, including all patients with ≥1 score from ≥1 reader from ≥1 reading wave, using the time (years) as an explanatory variable and adjusting for reader and wave. All outcomes were standardised, and the relative standardised rate of change was calculated (ie, the standardised rate of an outcome divided by the rate of a reference outcome). RESULTS: A total of 659 patients (46% males and mean age 33.6 years) were included. The most sensitive outcome to change in the SIJ (both MRI and radiographs) was the presence of ≥3 fatty lesions at a specific timepoint, with a relative standardised rate of change per year of 5.28 using the modified New York criteria as reference.Similarly, the most sensitive to change (in both MRI and radiographs) outcome in the spine was the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS; relative standardised yearly change 1.76) using ≥1 syndesmophyte as reference. CONCLUSION: MRI structural outcomes in the SIJ (ie, fatty lesions) are more sensitive to change than radiographic outcomes. Conversely, the mSASSS remains the most sensitive method, even when compared with MRI of the spine.

Comparative evaluation of screening tools for sarcopenia in patients with axial spondyloarthritis.

Sarcopenia is linked to chronic inflammation and muscle wasting. This research aims to compare the screening accuracy of tools for sarcopenia in axial spondyloarthritis (axSpA). A cross-sectional study involving 104 axSpA patients was conducted at Phramongkutklao Hospital between January 2020 and February 2021. Sarcopenia was diagnosed according to the AWGS 2019 criteria. Appendicular skeletal muscle mass was measured using DXA. SARC-F, SARC-CalF, and SARC-F+EBM, muscle strength, and physical performance were assessed. The screening tests were evaluated using ROC curves. The optimal cutoffs were identified with the Youden index. Most patients were male (74%), with a mean (SD) age and disease duration of 42.6 (12.22) and 8.3 (8.5), respectively. The prevalence of sarcopenia was 22.1%. The AUCs (95% CI) for calf circumference, SARC-F, SARC-CalF, SARC-F+EBM, handgrip strength, chair stand time, gait speed, and time and go test were 0.830 (0.734, 0.925), 0.509 (0.373-0.645), 0.782 (0.670-0.894), 0.856 (0.758-0.954), 0.710 (0.594-0.825), 0.640 (0.508-0.772), 0.689 (0.539-0.839), and 0.711 (0.576-0.846), respectively. The optimal cutoffs for SARC-F, SARC-CalF, and SARC-F+EBM were 1, 10, and 10, with sensitivity/specificity of 81.0%/29.7%, 90.5%/68.9%, and 77.3%/87.2%, respectively. Calf circumference, SARC-CalF, and SARC-F+EBM had the best performance to screen for sarcopenia in axSpA patients. Lowering the thresholds would potentially enhance the performances of SARC-CalF and SARC-F+EBM.

International Map of Axial Spondyloarthritis (IMAS): results from the perspective of 5557 patients from 27 countries around the globe.

BACKGROUND: The International Map of Axial Spondyloarthritis (IMAS) is a global initiative aimed to assess the impact and burden of axial spondyloarthritis (axSpA) and identify the unmet needs from the patient's perspective. METHOD: IMAS is a collaboration between the Axial Spondyloarthritis International Federation (ASIF), the University of Seville, Novartis Pharma AG and steered by a scientific committee. IMAS collected information through an online cross-sectional survey (2017-2022) from unselected patients with axSpA from Europe, Asia, North America, Latin America and Africa who completed a comprehensive questionnaire containing over 120 items. RESULTS: 5557 patients with axSpA participated in IMAS. Mean age was 43.9 ±12.8 years, 55.4% were female, 46.2% had a university education and 51.0% were employed. The mean diagnostic delay was 7.4 ±9.0 years (median: 4.0), and the mean symptom duration was 17.1 ±13.3 years. 75.0% of patients had active disease (Bath Ankylosing Spondylitis Disease Activity Index ≥4), and 59.4% reported poor mental health (12-item General Health Questionnaire ≥3). In the year before the survey, patients had visited primary care physicians 4.6 times and the rheumatologist 3.6 times. 78.6% had taken non-steroidal anti-inflammatory drug ever, 48.8% biological disease-modifying antirheumatic drugs and 43.6% conventional synthetic disease-modifying antirheumatic drugs. Patients's greatest fear was disease progression (55.9%), while the greatest hope was to be able to relieve pain (54.2%). CONCLUSIONS: IMAS shows the global profile of patients with axSpA, highlighting unmet needs, lengthy delays in diagnosis and high burden of disease in patients with axSpA worldwide. This global information will enable more detailed investigations to obtain evidence on the critical issues that matter to patients around the world to improve their care and quality of life.

Inflammation in the posterior elements, in particular the facet joint and facet joint ankylosis over 2-year follow-up in radiographic axial spondyloarthritis.

OBJECTIVES: To assess the association of posterior element (PE) and facet joint (FJ) inflammation with subsequent new FJ ankylosis (FJA) on MRI, in patients with radiographic axial spondyloarthritis (r-axSpA). METHODS: Patients from the Sensitive Imaging in Ankylosing Spondylitis cohort, inclusion criteria r-axSpA and ≥1 radiographic spinal syndesmophyte, were studied. MRI of the full spinal was performed at baseline, 1 and 2 years. PE/FJ inflammatory lesions and FJA were assessed per vertebral unit (VU) level by three readers. With multilevel time-lagged autoregressive generalised estimated equations, the association between PE/FJ inflammation and the subsequent development of FJA was investigated, taking the reader and VU levels into account. RESULTS: Out of the 58 patients with at least 2 reader scores available, mean age 49 (SD 10) years, 84% men, 59% had baseline PE inflammation, 24% had FJ inflammation and 26% had FJA. PE inflammation was more prevalent in the lower thoracic spine and FJ inflammation in the upper thoracic spine. VU with PE or FJ inflammation showed subsequent new FJA in two and one VU levels, respectively. The probability of developing FJA doubled with prior FJ inflammation. In multilevel analysis, FJ inflammation was associated with subsequent FJA (OR=3.8, 95% CI: 1.5 to 9.8), while no association was found between PE inflammation and new FJA (OR=1.2 (0.6-2.4)). CONCLUSIONS: FJ inflammation is rare in severe r-axSpA, but when present, the likelihood of developing subsequent FJA is over three times higher compared with FJ without inflammation. This finding contributes to the understanding of the relationship between inflammation and ankylosis at the same anatomical location in patients with axSpA.

Raftlin - a potential biomarker for axial spondyloarthritis and psoriatic arthritis: An observational study.

Our aim is to evaluate serum Raftlin levels as a biomarker for diagnosing and monitoring disease activity in patients with axial spondyloarthritis (axSpA) and Psoriatic arthritis (PsA). This trial included 40 axSpA patients, 40 PsA patients, and 40 healthy participants as the control group. Disease activity was assessed with Ankylosing Spondylitis Disease Activity Score for axSpA patients and The Disease Activity Index for Psoriatic Arthritis for PsA patients. The Spondyloarthritis Research Consortium of Canada index, health assessment questionnaire-disability index, and numeric rating scale were used to evaluate the enthesitis severity, disability, and pain status of all patients. Serum Raftlin levels were determined using the ELISA method. The 3 groups had no statistical differences regarding gender, age, weight, height, BMI, educational status, and exercise habits. The axSpA group had higher Raftlin levels than the PsA and control groups, and Raftlin levels were statistically significant in predicting the likelihood of axSpA. We found no statistically significant differences between the PsA and control groups. We found no statistically significant difference in Raftlin levels in HLA-B27 positive versus HLA-B27 negative patients in both axSpA and PsA groups. Our results also did not detect any correlation of Raftlin levels with Ankylosing Spondylitis Disease Activity Score, C-reactive protein, erythrocyte sedimentation rate, health assessment questionnaire-disability index, numeric rating scale, and Spondyloarthritis Research Consortium of Canada index in axSpA patients. Receiver operating characteristic analysis determined that Raftlin level ≥ 6.31 ng/mL discriminates axSpA from normal individuals with 92.5% sensitivity, 59% specificity, and an area under the curve of 0.738. Our results demonstrate that although serum Raftlin levels are elevated in axSpA patients, Raftlin cannot be used as an alone diagnostic marker for axSpA. Furthermore, it was not found to be related to the monitoring of disease activity, the level of pain, disability, or severity of enthesitis. This study is prospectively registered at www.clinicaltrials.gov (ID: NCT05771389).

Knowledge, perceptions, and practices of axial spondyloarthritis diagnosis and management among healthcare professionals: an online cross-sectional survey.

Spondyloarthritis (SpA) is a group of inflammatory disorders, including axial SpA (axSpA), characterized by inflammation in the spine and sacroiliac joints. Healthcare professionals have a crucial role in diagnosing and managing axSpA. Assessing their knowledge, perceptions, and practices is essential to enhance patient care. The objective of this study is to evaluate these factors by conducting an online survey. This online survey was performed using SurveyMonkey.com to assess healthcare professionals' knowledge, perceptions, and practices related to axSpA diagnosis, management, and monitoring. The questionnaire included questions about definitions, management strategies, monitoring approaches, treatment options, and barriers to care. Convenience sampling was used, and the data were analyzed descriptively by Microsoft Excel. One hundred sixty-four healthcare professionals participated; most respondents were rheumatologists from various geographic locations (27 countries). Most participants were familiar with axSpA definitions and diagnostic criteria, demonstrating high expertise. Variations were seen in follow-up intervals and diagnostic preferences, reflecting clinical heterogeneity. Seventy-two (43.9%) individuals had a multidisciplinary team, frequently including rheumatologists, physiotherapists, and radiologists. Of the participants, 73 (44.5%) had online/telephone follow-up sessions. The pharmacological and non-pharmacological treatment approaches varied, pointing to the importance of personalized care. Glucocorticoid use varied among countries. Recognizing inflammatory back pain, interpreting radiographs, and diagnosing early was essential to medical education. This study provides beneficial data on healthcare professionals' knowledge, perceptions, and practices regarding axSpA. While diagnostic familiarity and multidisciplinary approach are positives, there is a potential to standardize management, improve telemedicine services, remove barriers to physical activity, and optimize treatment options.

Exploring complement biomarkers in suspected axial spondyloarthritis.

OBJECTIVES: To investigate lectin pathway proteins (LPPs) as biomarkers for axial spondyloarthritis (axSpA) in a cross-sectional cohort with a suspicion of axSpA, comprising newly diagnosed axSpA and chronic low back pain (cLBP) individuals. METHODS: Serum samples from 515 participants within the OptiRef cohort, including 151 axSpA patients and 364 cLBP patients, were measured using immunoassays for LPPs (mannan-binding lectin (MBL), collectin liver-1 (CL-L1), M-ficolin, H-ficolin and L-ficolin, MBL-associated serine proteases (MASP)-1, -2 and -3, MBL-associated proteins (MAp19 and MAp44) and the complement activation product C3dg). RESULTS: Serum levels of L-ficolin, MASP-2 and C3dg were elevated in axSpA patients, whereas levels of MASP-3 and CL-L1 were decreased, and this remained significant for C3dg and MASP-3 after adjustment for C reactive protein (CRP). A univariate regression analysis showed serum levels of CL-L1, MASP-2, MASP-3 and C3dg to predict the diagnosis of axSpA, and MASP-3 and C3dg remained significant in a multivariate logistic regression analysis. Assessment of the diagnostic potential showed that a combination of human leukocyte antigen B27 (HLA-B27) and measurements of L-ficolin, MASP-3 and C3dg increased the diagnostic specificity for axSpA, however, with a concomitant loss of sensitivity. CONCLUSIONS: Serum levels of complement activation, that is, C3dg, and MASP-3 differed significantly between axSpA and cLBP patients after adjustment for CRP. Although combining HLA-B27 with measurements of L-ficolin, MASP-3 and C3dg increased the diagnostic specificity for axSpA, this seems unjustified due to the concomitant loss of sensitivity. However, both C3dg and MASP-3 were associated with axSpA diagnosis in multivariate logistic regression, suggesting an involvement of complement in the inflammatory processes and possibly pathogenesis in axSpA.

Navigating the complexity of pain in psoriatic arthritis and axial spondyloarthritis.

PURPOSE OF REVIEW: Pain is the most common and often most troublesome feature of chronic autoimmune diseases such as psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA). A predominant concept is that the main source of pain is from disease-induced tissue inflammation and structural damage, activating peripheral nerve fibers which relay to the central nervous system. This mechanism is nociceptive pain and the presumption has been that controlling inflammation will be sufficient to reduce this form of pain. However, despite control of inflammation, patients may still have significant residual pain. RECENT FINDINGS: We are learning that there are additional pain mechanisms, neuropathic and nociplastic, that are often operative in patients with rheumatologic conditions, that can significantly influence pain experience, quantitation of disease activity, and may benefit from therapeutic approaches distinct from immunotherapy. Neuropathic pain arises from diseased or damaged nerve tissue and nociplastic pain reflects sensitization of the central nervous system due to multiple genetic, neurobiologic, neural network dysregulation, and psychosocial factors. Pain arising from these mechanisms influence assessment of disease activity and thus needs to be factored into decision-making about immunotherapy efficacy. SUMMARY: This review addresses the importance of accurately assessing the complex mechanisms of pain experience in patients with PsA and AxSpA to more appropriately manage immunomodulatory, neuromodulatory, and nonpharmacologic therapies.

Disease modification in axial spondyloarthritis - still a controversy?

PURPOSE OF REVIEW: This review evaluates recent advancements in disease-modifying therapies for axial spondyloarthritis (axSpA). RECENT FINDINGS: A recent study could not demonstrate an additional effect of NSAID therapy on golimumab [Tumor Necrosis Factor-α inhibitor (TNFi)] on structural progression; however, this might be due to the fact that the study was underpowered. While DMARDs have shown promise in suppressing inflammation, their impact on structural progression remains uncertain. A well powered trial showed no difference in spinal progression between secukinumab [Interleukin17A inhibitor (IL17Ai)] and adalimumab-biosimilar (TNFi). Preliminary data on Janus kinase inhibitors (JAKi) focus on MRI findings but lack evidence on radiographic spinal progression. While some studies suggest promising outcomes, others reveal limitations and inconclusive findings. SUMMARY: Recent studies explore the effectiveness of NSAIDs, biological disease-modifying antirheumatic drugs like TNFi and IL-17i, as well as JAK inhibitors in axSpA. Conflicting evidence surrounds these therapies' ability to impede structural progression, with challenges in study design and interpretation. Moreover, changes in demographics and treatment methods underscore the importance of examining trends over time when assessing disease outcomes. Ultimately, ongoing research could benefit from new imaging tools when evaluating therapeutic strategies for modifying disease progression in axSpA.

Diagnosis, monitoring, and management of axial spondyloarthritis.

Axial spondyloarthritis (axSpA) is a chronic condition predominantly affecting the spine and sacroiliac joints. This article provides an in-depth overview of the current approaches to diagnosing, monitoring, and managing axSpA, including insights into developing terminology and diagnostic difficulties. A substantial portion of the debate focuses on the challenging diagnostic procedure, noting the difficulty of detecting axSpA early, particularly before the appearance of radiologic structural changes. Despite normal laboratory parameters, more than half of axSpA patients experience symptoms. X-ray and magnetic resonance imaging (MRI) are essential for evaluating structural damage and inflammation. MRI can be beneficial when there is no visible structural damage on X-ray as it can help unravel bone marrow edema (BME) as a sign of ongoing inflammation. The management covers both non-pharmacological and pharmacological approaches. Lifestyle modifications, physical activity, and patient education are essential components of the management. Pharmacological therapy, including nonsteroidal anti-inflammatory drugs (NSAIDs) and biologic disease-modifying anti-rheumatic drugs (bDMARDs), are explored, emphasizing individualized treatment. To effectively manage axSpA, a comprehensive and well-coordinated approach is necessary, emphasizing the significance of a multidisciplinary team. Telehealth applications play a growing role in axSpA management, notably in reducing diagnostic delays and facilitating remote monitoring. In conclusion, this article underlines diagnostic complexities and emphasizes the changing strategy of axSpA treatment. The nuanced understanding offered here is designed to guide clinicians, researchers, and healthcare providers toward a more comprehensive approach to axSpA diagnosis and care.

Comparative study of two laboratory techniques for the detection of HLA-B27 in patients with axial spondyloarthritis: a cross-sectional analysis.

BACKGROUND: The diagnostic and prognostic relevance of Human Leukocyte Antigen B-27 (HLA-B27) in Axial Spondyloarthritis (AxSpA) is undeniable, with 70% of Ankylosing Spondylitis (AS) patients carrying the B27 gene, contrasted with a mere 4.35% in the general population. Flow cytometry (FC) and Polymerase Chain Reaction (PCR) have emerged as the predominant techniques for routine HLA-B27 typing. While various studies have compared these methods, none have catered to the unique characteristics of the Brazilian demographic. Therefore, this research aims to compare FC and PCR in a Brazilian cohort diagnosed with AxSpA. METHODS: An analytical cross-sectional study was undertaken involving 62 AxSpA outpatients from a Brazilian University Hospital. Both FC and PCR-SSP assays were utilized to ascertain HLA-B27 typing. The outcomes (either confirming or refuting the allele's presence) underwent rigorous scrutiny. Agreement between the methodologies was assessed using the kappa statistic. A p-value of < 0.05 was deemed statistically significant. RESULTS: Of the participants, 90.3% (n = 56) were HLA-B27 positive according to FC, while 79% (n = 49) were identified as positive using the PCR method. FC exhibited a sensitivity rate of 98% paired with a specificity of 38.5%. The Positive Predictive Value for FC stood at 85.7%, and the Negative Predictive Value was 83.5%. Consequently, the overall accuracy of the FC method was gauged at 85.5%. A kappa coefficient of κ = 0.454 was derived. CONCLUSIONS: FC demonstrated noteworthy sensitivity and satisfactory accuracy in HLA-B27 detection, albeit with a reduced specificity when contrasted with PCR-SSP. Nevertheless, given its cost-effectiveness and streamlined operation relative to PCR, FC remains a pragmatic option for preliminary screening in clinical practice, especially in low-income regions. To optimize resource allocation, we advocate for a refined algorithm that initiates by assessing the relevance of HLA-B27 typing based on Choosing Wisely recommendations. It then leans on FC, and, if results are negative yet clinical suspicion persists, advances to PCR. This approach aims to balance diagnostic accuracy and financial prudence, particularly in regions contending with escalating medical costs.

Comparison of clinical characteristics between patients with axial spondyloarthritis with and without acute anterior uveitis: a multicentre study of the Chinese Spondyloarthritis Registry.

OBJECTIVES: This study explores the clinical characteristics associated with the occurrence of acute anterior uveitis (AAU) in patients with axial spondyloarthritis (axSpA) within a large, multicentre database. METHODS: This observational, cross-sectional study of patients with axSpA used data from the Chinese Spondyloarthritis Registry between August 1, 2018, and March 31, 2020. The demographic and clinical features of patients with and without AAU were compared. Univariate and multivariate analyses were performed to determine the association between variables and uveitis. RESULTS: A total of 4304 patients were included in this study. The prevalence of AAU in patients with axSpA was 10.59%. Multivariate logistic regression analysis revealed a positive correlation between AAU and age at diagnosis (odds ratio [OR], 1.026; p<0.001), disease duration (OR, 2.117; p<0.001), current or past Achilles tendinitis (OR, 1.692; p<0.001), current or past dactylitis (OR, 1.687; p=0.002), current or past psoriasis (OR, 3.932; p<0.001), presence of human leukocyte antigen-B27 (HLA-B27) (OR, 2.787; p<0.001), and a good response to non-steroidal anti-inflammatory drugs (NSAIDs) (OR, 1.343; p=0.027). CONCLUSIONS: AAU was the most common extra-articular manifestation in the Chinese Spondyloarthritis Registry. In Chinese patients with axSpA, older age at diagnosis, longer disease duration, presence of HLA-B27, current or past Achilles tendinitis, current or past dactylitis, current or past psoriasis, and a good response to NSAIDs were positively associated with AAU.