Patients with ANCA-associated vasculitis (AAV) are at increased risk of osteoporosis due to multiple disease- and treatment-related factors. However, real-world data on osteoporosis screening practices in this population remain limited. The aim of this study was to assess osteoporosis screening practices and the prevalence of reduced bone mineral density (BMD) in patients with AAV using a nationwide registry, and to identify factors associated with osteoporosis. This nationwide, retrospective, web-based study was conducted using the Turkish Vasculitis Study Group (TRVaS) database, including patients diagnosed with AAV between January 2000 and December 2023. Patients were evaluated for osteoporosis screening using dual-energy X-ray absorptiometry (DXA) and categorized according to BMD status. Clinical characteristics and potential risk factors were analyzed, and multivariable logistic regression was performed to identify independent predictors of osteoporosis. A total of 528 patients were included (median age 56 years [interquartile range 43–66]; 57.8

Objective: This study evaluates the effectiveness, retention rate and safety of baricitinib, including a comparison between baricitinib and a tumour necrosis factor inhibitor (adalimumab) in a real-life cohort of patients with rheumatoid arthritis (RA). Methods: RA patients from the Hacettepe University Biological Prospective Database who received at least one dose of baricitinib or adalimumab between June 2020 and January 2023 were analyzed. Drug survival analysis included patients with at least one dose, while efficacy and safety analyses required at least one follow-up visit. Adverse events, major adverse cardiovascular events (MACE), malignancies, and medication adherence were assessed. The European Alliance of Associations for Rheumatology (EULAR) response classified patients as either good responders or non-responders. Results: A total of 280 patients (86 baricitinib, 194 adalimumab) were included, with a mean age of 52.4 (±13.6) years; 77.5% were female. Baricitinib significantly improved disease activity parameters. High patient global assessment [odds ratio (OR): 1.05 (95% confidence interval (CI): 1.02-1.09)] predicted a good response, while RF positivity [OR: 7.66 (95% CI: 1.46-40.07)] indicated a poor response. MACE occurred in 2 patients (2.5%) on baricitinib and in 4 patients (2.5%) on adalimumab, with rates of 15.3 and 9.1 per 1000 patient-years, respectively (p=0.20). Conclusion: Baricitinib improved disease activity parameters and a high patient global assessment predicted a good EULAR response. MACE incidence was comparable to that with adalimumab.

The clinical benefit of combining leflunomide (LEF) with tumor necrosis factor inhibitors (TNFi) in psoriatic arthritis (PsA) remains uncertain. We aimed to evaluate the efficacy and treatment durability of LEF-TNFi compared with non-LEF regimens (predominantly methotrexate (MTX)-TNFi and TNFi monotherapy). This retrospective cohort included 492 biologic-naive PsA patients initiating TNFi (2003–2020): LEF–TNFi (n = 85) versus non-LEF (n = 407). Multiple imputation addressed missing data, and propensity score matching (7 covariates; caliper 0.2 standard deviations of the logit-propensity score) addressed confounding by indication. Longitudinal outcomes were analyzed using linear mixed-effects models; treatment modification was evaluated via Cox models. Reasons for treatment modification were examined descriptively using a competing risks framework. Substantial baseline imbalances (23 of 36 variables with standardized mean difference > 0.10) were eliminated by propensity score matching (0 of 7 matching covariates with SMD > 0.10; 96.9

OBJECTIVES:To integrate evidence-based data with expert opinion to provide guidance for the diagnosis, follow-up and treatment of giant cell arteritis (GCA). METHODS:A systematic literature review (SLR) was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. To structure the key clinical questions, the task force employed the Population, Intervention, Comparison Outcome (PICO) format. The Oxford system was subsequently applied to grade the quality of the evidence and determine the strength of each recommendation. RESULTS:This guideline provides 16 recommendations. We recommend the use of methotrexate in addition to glucocorticoids as first-line treatment in all patients with GCA without ischaemic symptoms. We recommend leflunomide, azathioprine and mycophenolate mofetil as alternatives in these patients if methotrexate is not tolerated. We recommend tocilizumab in GCA patients with ischaemic symptoms or with refractoriness to at least one conventional immunosuppressive. We also recommend upadacitinib as an alternative to tocilizumab in patients with low cardiovascular risk. To our knowledge, our recommendations are the first recommending upadacitinib as an alternative treatment option for the treatment of GCA. CONCLUSIONS:The large RCTs assessing and comparing new effective options are still required in GCA. Assessment of the value of conventional immunosuppressives, which are more cost-effective options compared to biologic agents, is another research area in GCA treatment especially for developing countries. Upadacitinib seems to be a promising option in GCA. However, more real-life experience is needed to assess the safety of upadacitinib in the elderly population with especially high cardiovascular risk.

Background: Traumatic dental avulsion is a severe dental injury that requires immediate management to preserve the periodontal ligament and ensure tooth survival. Because many clinical factors interact, predicting the prognosis is difficult. This study evaluated the performance of 5 conversational artificial intelligence (AI) models—ChatGPT-4o, Google Gemini, Microsoft Copilot, Perplexity AI, and Grok—in predicting avulsion prognosis compared with a guideline- based reference derived from the International Association of Dental Traumatology (IADT). Methods: A total of 120 synthetically generated avulsion scenarios were created by combining clinical parameters including extraoral dry time, storage medium, and root development stage. Each model predicted both numerical (0-12) and categorical (good/guarded/poor) prognosis twice (T1 and T2, 48 hours apart) under deterministic conditions. Agreement with the guideline- based reference was assessed using accuracy, macro-F1, and Cohen’s κ, while temporal stability was analyzed via McNemar’s test. Consensus accuracy was determined through majority voting. Results: None of the models achieved full agreement with the guideline-based reference. Perplexity demonstrated the highest κ value at T1 (0.575), while ChatGPT-4o achieved the highest accuracy at T2 (0.783). Gemini showed the greatest temporal stability (92.5%), and the majority-vote consensus improved overall reliability (κ = 0.698). Mean absolute errors ranged between 1.56 and 2.65, indicating moderate numerical concordance. Conclusion: Conversational AI models exhibited moderate agreement with IADT-based prognosis predictions but differed in temporal consistency. The consensus approach yielded superior reliability, underscoring the potential of ensemble AI strategies as supportive—not substitutive— tools in clinical decision-making for dental trauma management.

Objectives: To evaluate clinical characteristics, biological disease-modifying antirheumatic drugs (bDMARD) treatment response and drug retention in patients with axial spondyloarthritis (axSpA) with advanced spinal ankylosis or bamboo spine, compared with patients without syndesmophytes. Methods: Patients from the Hacettepe University Rheumatology Biologic Registry who had available cervical and lumbar radiographs were classified into three groups: advanced spinal ankylosis, bamboo spine, and a control group with at least ten-year disease duration and without syndesmophytes. Baseline characteristics, treatment responses [Bath Ankylosing Spondylitis Disease Activity Index 50 (BASDAI50) and Assessment of Spondyloarthritis International Society partial remission (ASAS-PR)], and retention of first bDMARDs were evaluated. Results: Of 770 patients, 99 had advanced spinal ankylosis, 78 had bamboo spine, and 92 constituted the control group. Patients with advanced structural damage were older, more often male, and had higher body mass index, greater smoking exposure, and more frequent hip involvement. Baseline disease activity was similar across groups. At follow-up, BASDAI50 and ASAS‑PR responses were comparable among advanced spinal ankylosis, bamboo spine, and controls. Median retention of first bDMARDs did not differ significantly between groups (log‑rank p=0.86). One‑year retention rates were 75% (no syndesmophytes), 84% (advanced spinal ankylosis), and 78% (bamboo spine); at 5 years, retention rates were 67%, 64%, and 60%, respectively; and at 10 years, retention rates were 50%, 41%, and 43%, respectively. Median drug survival ranged from 104 to 126 months across groups. Conclusion: Patients with advanced spinal ankylosis or bamboo spine achieve meaningful clinical improvement with bDMARD therapy and demonstrate long-term drug retention comparable to that of axSpA patients without syndesmophytes, supporting the initiation and continued use of bDMARDs in this population.

Objective: To perform the cultural adaptation of the Health Literacy in Dentistry Scale-29 (HeLD-29) for Turkish adults and to evaluate its validity and reliability. Design: The Turkish version of the HeLD-29 was adapted through a forward-backward translation procedure consistent with the original 29-item, seven-subscale structure. The scale was first translated into Turkish by two independent translators and then back-translated into English by two different translators. The final analytical sample included 298 adults aged 19-70 years (117 females, 181 males). To assess temporal stability, 60 randomly selected participants completed the scale again after 7-10 days. Results: Test-retest reliability demonstrated excellent agreement using the Intraclass Correlation Coefficient (ICC = 0.912; p < 0.001). The Spearman rank-order correlation also indicated very strong temporal stability (r = 0.920; p < 0.001). After excluding two outliers, EFA revealed adequate communalities (0.546-0.894) and supported the multidimensional structure, with the final 26-item version explaining 78.07% of the total variance. Internal consistency was high across subscales (α = 0.84-0.93) and for the total scale (α = 0.936), and split-half coefficients further confirmed strong reliability. CFA verified the validity of the multidimensional construct, demonstrating acceptable model fit after minor modifications (RMSEA = 0.063; GFI = 0.900; AGFI = 0.850; CFI = 0.943; χ2 = 606.465; p < 0.001). Conclusion: The Turkish version of the HeLD-29 was demonstrated to be a reliable and valid instrument for assessing oral health literacy in Turkish adults.

Objective: This study aimed to investigate the frequency and progression of pelvic and hip entheseal structural changes in PsA patients initiating biologic therapy. Methods: Records from the Hacettepe University Rheumatology Biologic Therapy Registry (HUR-BIO) were retrospectively reviewed. PsA patients with pelvic radiographs obtained within ±1 year of biologic therapy initiation were included. Radiographs were assessed according to the modified New York criteria, and entheseal involvement at the ischium, symphysis pubis, iliac wings and greater/ lesses trochanter was graded from 0 (none) to 4 (florid new bone formation). Grade 2 or higher was considered clinically relevant. Demographic and clincal characteristics were compared between patients with/ without structural changes and progression of these lesions were assessed. Results: A total of 108 patients (68.5% female; mean age 41.5 ± 11.6 years; mean PsA duration 2.2 years) were included. Baseline mNY positivity was detected in 45.4%. Bilateral relevant entheseal involvement was observed in 21.9% at the ischium, 15.3% at the symphysis pubis, and 7.7% at the iliac wings. Greater trochanteric enthesopathy was 2% on the right side. Male patients, with higher BMI and older age with family history tended to have more structural lesions. After a mean follow-up of 38.6 months, data from 48 patients were available. Most progression was limited to a one-grade increase at the ischium (28%). Conclusion: Major pelvic entheseal lesions, predominantly at the ischium and symphysis pubis, are relatively common in PsA but show minimal radiographic progression under biologic therapy.

OBJECTIVES:Pain in PsA is common and multifactorial, involving nociceptive, neuropathic and nociplastic mechanisms. We hypothesized that PsA patients with entheseal pain exhibit distinct brain activation patterns on functional MRI (fMRI), depending on the presence of US-detected inflammation. METHODS:PsA patients underwent clinical evaluation, US assessment of the Achilles tendon and fMRI brain imaging. Participants were grouped as follows: Group 1-clinical Achilles enthesitis with active US findings (hypoechogenicity and Doppler ≥grade-2); Group 2-clinical enthesitis but negative US; Group 3-no clinical or US evidence of enthesitis. The primary comparison (Groups 1 vs 2) evaluated whether US-confirmed inflammation is associated with distinct fMRI patterns. The secondary comparison (Groups 1 vs 3) aimed to distinguish inflammation-specific responses from general disease-related changes. RESULTS:Sixteen PsA patients were included. Group 1 showed significantly higher activation in brain regions involved in pain modulation, cognitive processing and attention compared with Group 2 [(middle frontal gyrus T-score: 6.92, P-value: 0.009), (inferior triangularis T-score: 4.53, P-value: 0.009), (inferior parietal lobule triangularis T-score: 5.94, P-value: 0.015), (supramarginal gyrus T-score: 5.28, P-value: 0.015), (superior medial FG T-score: 4.88, P-value: 0.022)]. Regarding comparison for pain-positive vs pain-negative patients, Group 1 had more activity than Group 3 in the supramarginal gyrus and inferior parietal lobule. CONCLUSION:US-detected entheseal inflammation may be associated with distinct central pain-processing features, supporting the role of US as a useful tool for identifying underlying inflammatory mechanisms in PsA-related pain. Understanding the interaction between peripheral inflammation and central sensitization may guide more personalized and effective pain management strategies.

Psoriatic arthritis (PsA) is a chronic inflammatory musculoskeletal disease that develops in a substantial proportion of patients with psoriasis (PsO). Understanding its epidemiology is essential for improving early recognition, risk stratification, and preventive strategies. This review summarizes current evidence on the global prevalence and incidence of PsA in both the general population and among individuals with PsO. Population-based studies estimate PsA prevalence at approximately 0.1-0.2%, with considerable geographic variability. Among patients with PsO, approximately 20% develop PsA, although this proportion varies according to age, disease severity, classification criteria, and region. Incidence rates in the general population range from 3 to 41 per 100,000 person-years, with evidence of increasing prevalence over time in several countries, likely reflecting improved recognition and diagnostic practices. Risk factors for PsA development include severe PsO, nail involvement, obesity, and the presence of musculoskeletal symptoms, particularly inflammatory arthralgia. Emerging data suggest that advanced systemic therapies for PsO may influence future PsA incidence, although prospective evidence is still needed. Significant heterogeneity in epidemiological estimates is driven by methodological differences, diagnostic criteria, healthcare systems, and underdiagnosis. A better understanding of epidemiological trends and transition phases from PsO to PsA may support earlier identification and optimized multidisciplinary management strategies.

Objective: The pathogenesis of ankylosing spondylitis (AS) involves both genetic and environmental factors. This study aimed to investigate whether shared living spaces increase the risk of AS development in the spouses of patients with AS. Methods: The study included consecutive AS patients from the Hacettepe University Rheumatology Clinic (November 2021-June 2022) diagnosed using the Assessment of SpondyloArthritis international Society (ASAS) criteria. This research was conducted using a cross-sectional design. Spouses with reported AS were evaluated to confirm diagnoses. Confirmed AS cases were included, while undiagnosed inflammatory low back pain cases were excluded. Two rheumatologists independently assessed the spouses using pelvic radiography and sacroiliac magnetic resonance imaging, if needed. Standardized incidence ratios (SIRs) were calculated by dividing the observed number of cases by the expected number of cases, derived from age- and sex-specific incidence rates applied to the person-years at risk. Results: Among the 680 patients, 582 (85.6%) had AS, 72 (10.6%) had non-radiographic axial spondyloarthritis, and 26 (3.8%) had peripheral spondyloarthritis. The mean follow-up was 10.6 (±7.9) years. Spouses of 7 patients (1.2%, 95% CI: 0.5-2.5) met the ASAS criteria for AS. Excluding 2 patients diagnosed before marriage, the prevalence of AS among spouses was 5/580 (0.86%, 95% CI: 0.3-2). Over 12 635 person-years of marriage, 5 new AS cases were observed vs. 0.82 expected (SIR: 6.1, 95% CI: 2.0-14.2). Among unrelated spouses, 3 post-marriage AS cases were observed over 12 613 person-years, yielding an SIR of 3.65 (95% CI: 0.75-10.68). Conclusion: Among spouses living in the same environment, the diagnosis of AS increased by approximately sixfold. Even after excluding consanguineous couples, the incidence of AS remained higher than expected among unrelated spouses, although the statistical significance was limited by the small number of observed cases. This observation may suggest a role for shared environmental factors in the development of AS.

Objectives Behçet disease (BD) is a complex vasculitis with both autoimmune and autoinflammatory features. Despite specific clinical features, no laboratory tests are available for the diagnosis of BD. We recently found that BD sera exhibited immunoreactivity against neurofilament medium protein (NF-M). This study aimed to replicate this finding in an independent cohort and to assess the specificity and sensitivity of NF-M immunoreactivity in serum samples obtained from BD, systemic lupus erythematosus (SLE), multiple sclerosis (MS), psoriatic arthritis (PsA) and non-Behçet uveitis (NBU) patients as well as healthy donors.Methods Serum samples from 76 patients (33 BD, 16 MS, 15 SLE, 9 PsA and 3 NBU) and 22 healthy donors (totalling 98 sera) were analysed. Mouse brain tissue sections were immunolabelled with the sera and examined using confocal microscopy.Results 97% (32/33) of BD patient sera exhibited a distinct fine filamentous staining pattern consistent with NF-M protein immunolabelling in axons, while sera from healthy controls and patients with SLE, MS, PsA and NBU showed no similar staining. Conversely, MS patient sera displayed a thick filamentous staining pattern attributed to oligodendrocytes and their myelin-forming processes. SLE patient sera intensely labelled all cell nuclei, conforming to immunoreactivity against nuclear antigens.Conclusions These findings reveal the ubiquitous presence of NF-M immunoreactivity, reportedly cross-reacting with bacterial heat shock protein 65, in BD sera. This common and specific immunoreactivity may serve as a valuable tool for diagnosing BD. Additionally, the data confirm the unique potential of connective tissue-poor brain sections for identifying sero-immunoreactivity.

Objectives:There is no consensus on how musculoskeletal ultrasound (US), especially power Doppler (PD) positivity, should inform treatment decisions in RA. We aimed to summarize the literature on whether PD positivity can predict response to intensification of RA therapies in patients with moderate to high clinical disease activity. Methods:A systematic literature review was performed using a predefined PICO strategy. The titles and abstracts, and subsequently full texts, were independently screened and reviewed by two reviewers and any disagreement was resolved by a third investigator. Studies that investigated the predictive value of PD were included. Results:Among 2580 abstracts/titles, 13 studies were included. Studies were heterogeneous regarding the inclusion criteria, baseline and new treatments, scanned joints and follow-up duration. In eight studies, patients with higher baseline PD activity had a better response to treatment, mostly with higher reductions in clinical indices. In contrast, two studies found that the probability of achieving clinical remission decreased as the baseline PD score increased. There was no association between baseline PD and the achievement of clinical remission at the follow-up in the remaining three studies. Conclusion:The baseline Doppler severity may suggest better improvement with higher reductions in composite scores, but this may not be enough to predict a remission state. How US can be used to predict response in RA management requires a well-designed study that will need to be shaped by the existing observations, most importantly identifying the outcome measure that will also be important for daily practice.

PURPOSE:In this study, we aimed to characterize the role of magnetic resonance imaging (MRI) in making a specific diagnosis of inflammatory hand arthritis (IHA), particularly in early stages or ambiguous cases. METHODS:Patients aged ≥18 years with suspicious IHA in at least one joint were enrolled in this single-center prospective study. Three Tesla MRI (3T-MRI) with a fine-tuned protocol was utilized, whereby differential diagnoses were made by radiologists according to the predominant involvement of synovium or synovioentheseal complex (SEC) and/or specific degenerative findings. Physical examination, laboratory findings, treatment response, and already-established classification criteria were used to reach the final diagnostic groups: psoriatic arthritis (PsA), rheumatoid arthritis (RA), erosive osteoarthritis or calcium pyrophosphate dihydrate deposition disease (EOA/CPPD), and arthritis with distal interphalangeal joint (DIPJ) involvement (ADIPI) not otherwise classified into any group. Statistical analyses mainly included pairwise comparisons of MRI findings across diagnostic groups. RESULTS:Of 80 patients enrolled, 57 [42 women; mean age, 54 years (range, 28-79 years)] constituted the final group with eventual clinical diagnoses of 11 PsA, 14 RA, 11 EOA/CPPD, and 21 ADIPI. MRI revealed no difference between the PsA and ADIPI groups, except for nailbed enthesitis (P = 0.048, effect size: 0.416). A comparison between PsA and RA revealed that enthesitis, excluding pulley enthesitis, was more frequently observed in PsA (P = 0.033, effect size: 0.497). Periarticular soft tissue edema was also more common in PsA than RA (P = 0.042, effect size: 0.461). When the ADIPI and PsA groups were combined, enthesitis and periarticular soft tissue edema were more common than in other groups (P < 0.001). CONCLUSION:SEC inflammation and periarticular edema on MRI strongly predict PsA, especially in patients with DIPJ arthritis who do not meet rheumatological classification criteria. CLINICAL SIGNIFICANCE:3T-MRI with a fine-tuned protocol enables a more accurate differential diagnosis of hand inflammatory arthritis, potentially guiding earlier and more targeted interventions.

OBJECTIVE:This study aims to assess the incidence and factors linked to venous thromboembolic events (VTE) in a large national cohort of antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) from the Turkish Vasculitis Study Group (TR-VaS). METHOD:This retrospective analysis included patients with granulomatosis with polyangiitis, microscopic polyangiitis, renal-limited vasculitis, and eosinophilic granulomatosis with polyangiitis. VTE that occurred within 3 months before the diagnosis of AAV or during the follow-up period was classified as AAV-associated VTE (AAV-VTE). Demographic, clinical, and disease-related features, along with the presence of well-known VTE risk factors, were compared between AAV patients with and without VTE. Multivariate analyses were performed to identify independent risk factors linked to the development of AAV-VTE. RESULTS:A total of 559 patients were included, and VTE was detected in 43 (7.7%). In univariate analysis, baseline body mass index (BMI) (HR: 1.13, 95% CI: 1.02-1.25, p = 0.01), erythrocyte sedimentation rate (HR: 1.01, 95% CI: 1.00-1.02, p = 0.04), BVAS score (HR: 1.05, 95% CI: 1.01-1.09, p = 0.01), renal involvement (HR: 2.01, CI: 0.96-4.20, p = 0.06), the presence of immobilization (HR: 11.4, 95% CI: 5.64-23.37, p < 0.001), and trauma (HR: 28.84, 95% CI: 3.5-215.7, p < 0.001) were identified as risk factors for VTE-AAV. In multivariate analysis, baseline BMI (HR: 1.14, CI: 1.02-1.26, p = 0.002) was the only independent risk factor for the development of VTE. CONCLUSION:Our findings suggest that physicians caring for AAV patients should be cautious about the risk of VTE in patients with an elevated BMI and active disease, along with other recognized risk factors for VTE.

Objective:There are national and international guidelines on the optimal use of disease-modifying anti-rheumatic drugs. In this study, we aimed to provide critical insights into the real-world efficacy and adherence of these DMARDs, providing a data-driven basis for optimizing treatment paradigms for RA within the national healthcare framework. Methods:This nationwide cohort study utilized data from the Turkish Ministry of Health National Electronic Database, known as E-Pulse between January 2016 and December 2022. In this analysis, cases of RA were identified using ICD-10 codes two times at least 30 days apart Treatment prescriptions were recorded based on their prescription at baseline and follow-up. Results:There were a total of 347,902 RA (79.5% female) patients in the E-Pulse system. The mean (SD) age of RA patients was 59.1 (14.8) years Methotrexate and sulfasalazine (35.1% vs 30.5%, OR 95% CI 0.81 usage was more common in men and hydroxychloroquine was more common in women 46.764 (13.4%) patients were prescribed bDMARD and/or tsDMARD 494.499 times. AntiTNF drugs are the most commonly prescribed drugs. This is followed by B-cell blockers, JAK inhibitors, anti-IL6 and T-cell blockers. Conclusion:Turkish national health database highlights the widespread use of synthetic DMARDs in treating rheumatoid arthritis (RA). While traditional DMARDs like methotrexate and hydroxychloroquine are favored the cautious use of advanced therapies, particularly anti-TNFs, suggests a potential for optimizing treatment protocols.

Background: The literature suggests the possibility of an increased prevalence of cervical diffuse idiopathic skeletal hyperostosis (DISH) in spondyloarthritis (SpA), based on case reports or studies that were not designed to investigate this specific question. Objectives: Our aim is to compare the frequency of cervical DISH in SpA vs age and sex-matched controls to see whether there is a true increased frequency and if the presence of SpA impacts the onset age of DISH. Methods: Adult patients with age ≥18 were included. The SpA population included patients who were diagnosed with axial or peripheral SpA, followed at the Arthritis Centre and had cervical spine x-rays for screening purposes in keeping with the standard of practice of a single rheumatologist between 2016-2020. The control group included patients who presented to the Emergency Department and had a cervical spine x-rays for any reason, and there were 4 control patients for each SpA patient who were age and sex-matched. An investigator meeting on the definitions took place prior to the study, followed by an agreement exercise. Two radiologists independently scored the xrays for the level of confidence for the presence of DISH, on a scale between 0-5. The ICC of the two radiologists were 0,935. For the study, the xrays were read by one of the two radiologists for any new bone formation, flowing ossification, bony spur, osteophyte, exuberant osteophytosis, syndesmophyte, floating mineralization, bridging and facet joint ankylosis and overall impression; equally distributing the cases and controls among the two radiologists. The confidence of ≥Grade 3 was considered DISH positive. Here, we present the data on DISH only. Results: One hundred ninety-one SpA and 764 age- and sex-matched controls were included. The mean (SD) age of SpA patients was 45.6 (13.4) years and 87 (45.5%) were women, being similar to the controls (p=1.00 and p=1.00, respectively). Eighty-three patients (43.4%) were diagnosed with psoriatic arthritis, 78 (40.8%) patients with radiographic axial SpA, 20 (10.5%) patients with non-radiographic axial SpA, and 10 (5.3%) patients with inflammatory bowel disease-related SpA. Within the whole group, 81 (42.4%) had isolated axial involvement according to the following rheumatologist, 36 (18.8%) had peripheral involvement, and 74 (38.7%) had axial and peripheral involvement. DISH was observed in 26 (13.6%) SpA patients and 108 (14.1%) controls, with similar frequency (p=0.852). The age of DISH+ patients was statistically significantly lower in the SpA group than the control group (median (IQR); 54 (16) vs 59 (13); p=0.026) (Figure 1). DISH was higher in males in both SpA and control groups (p=0.04 and p=0.003, respectively). There were 143 (74.9%) SpA patients with known HLA-B27 status. The frequency of DISH in HLA-B27(-) SpA patients was higher than HLA-B27(+) SpA patients numerically (n=14/65 (21.5%) vs n=8/78 (10.3%); p=0.063). Interestingly, HLA-B27 had different effects on the presence of DISH in subgroups: AxSpA patients (radiographic and non-radiographic combined) had more DISH if they were HLA-B27 positive (12.5% vs 8.7%), unlike the psoriatic arthritis patients, who had DISH exclusively if they were HLA-B27 negative (28.2% vs 0%). Conclusion: The frequency of DISH in SpA patients was found to be similar to the general population. However, SpA patients tended to develop DISH at an earlier age. Our observation on the differential impact of HLA-B27 on axSpA vs PsA may be a signal on the different mechanisms impacting the spine in both diseases. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: Sibel Aydin Abbvie, Jannsen, Novartis, Pfizer, and UCB, Abbvie, Celgene, Eli Lilly, Novartis, Pfizer, Sanofi, and UCB, Abbvie, Celgene, Eli Lilly, Jannsen, Novartis, Pfizer, Sanofi, Novartis, and UCB, Nicole Hryciw: None declared, Baljot Chahal: None declared, Seyyid Bilal Açikgöz: None declared, Gizem Ayan: None declared, Ummugulsum Gazel: None declared, Zaid Jibri: None declared, Marcos Loreto Sampaio: None declared.