EULAR recommendations for the use of imaging in large vessel vasculitis in clinical practice: 2023 update.

OBJECTIVES: To update the EULAR recommendations for the use of imaging modalities in primary large vessel vasculitis (LVV). METHODS: A systematic literature review update was performed to retrieve new evidence on ultrasound, MRI, CT and [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) for diagnosis, monitoring and outcome prediction in LVV. The task force consisted of 24 physicians, health professionals and patients from 14 countries. The recommendations were updated based on evidence and expert opinion, iterating until voting indicated consensus. The level of agreement was determined by anonymous votes. RESULTS: Three overarching principles and eight recommendations were agreed. Compared to the 2018 version, ultrasound is now recommended as first-line imaging test in all patients with suspected giant cell arteritis, and axillary arteries should be included in the standard examination. As an alternative to ultrasound, cranial and extracranial arteries can be examined by FDG-PET or MRI. For Takayasu arteritis, MRI is the preferred imaging modality; FDG-PET, CT or ultrasound are alternatives. Although imaging is not routinely recommended for follow-up, ultrasound, FDG-PET or MRI may be used for assessing vessel abnormalities in LVV patients with suspected relapse, particularly when laboratory markers of inflammation are unreliable. MR-angiography, CT-angiography or ultrasound may be used for long-term monitoring of structural damage, particularly at sites of preceding vascular inflammation. CONCLUSIONS: The 2023 EULAR recommendations provide up-to-date guidance for the role of imaging in the diagnosis and assessment of patients with LVV.

Drug retention rate and predictive factors of drug survival for secukinumab in radiographic axial spondyloarthritis.

The drug retention rate has been an important indicator for evaluating the treatment tolerance. Unfortunately, our knowledge of the secukinumab retention rate in radiographic axial spondyloarthritis (r-AxSpA) is limited. The objective of this study was to assess the retention rate of secukinumab and evaluate predictive factors of drug survival based on data from a real-life cohort. We retrospectively assessed 147 r-AxSpA patients between May 2018 and January 2020 from the HUR-BIO database. Secukinumab retention rates were analyzed using the Kaplan-Meier method and Cox proportional hazard model was used for predictors factors. The global retention rate of secukinumab was 55% at 12 months. r-AxSpA patients with obesity had a lower frequency of secukinumab discontinuation (29% vs. 50%, p = 0.013) in comparison r-AxSpA patients without obesity. In multivariate analysis, multiple TNFi usage had a higher risk of secukinumab discontinuation [HR 1.99 (1.09-3.62), p = 0.024]; on the other hand, obesity had a lower risk [HR 0.45 (0.27-0.90), p = 0.008]. Except for not using multiple TNFi, this real-life analysis showed for the first time that obesity is not an adverse risk factor for secukinumab drug retention in r-AxSpA. Secukinumab, which is an interleukin-17A inhibitor, could act via a different pathway than tumor necrosis factor inhibitors (TNFi). The identification of predictive factors such as obesity that may affect the individual drug selection may provide more appropriate biologic treatment strategies for r-AxSpA.

Somatic mutations in rheumatological diseases: VEXAS syndrome and beyond.

Discovery of the VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome demonstrates that somatic mutations in haematological precursor cells can cause adult-onset, complex inflammatory disease. Unlike germline mutations, somatic mutations occur throughout the lifespan, are restricted to specific tissue types, and may play a causal role in non-heritable rheumatological diseases, especially conditions that start in later life. Improvements in sequencing technology have enabled researchers and clinicians to detect somatic mutations in various tissue types, especially blood. Understanding the relationships between cell-specific acquired mutations and inflammation is likely to yield key insights into causal factors that underlie many rheumatological diseases. The objective of this review is to detail how somatic mutations are likely to be relevant to clinicians who care for patients with rheumatological diseases, with particular focus on the pathogenetic mechanisms of the VEXAS syndrome.

Use of 18F-fluorodeoxyglucose positron emission tomography to standardize clinical trial recruitment in Takayasu's arteritis.

OBJECTIVES: To assess whether data from 18F-fluorodeoxyglucose (FDG) PET should be incorporated into eligibility criteria for clinical trials in Takayasu's arteritis (TAK). METHODS: The study was conducted in two parts. Part one was an international online survey among physicians with experience managing TAK to determine, using clinical vignettes, whether FDG-PET data influence decisions about enrolment in trials. Part two used patient data from an observational cohort study in TAK to assess agreement regarding decisions about enrolment into trials, based on clinical assessment with and without incorporation of FDG-PET data. RESULTS: In part one, 68 physicians responded to the survey. Most physicians had used FDG-PET to diagnose TAK (82%) or monitor disease activity (66%). In vignettes representing active clinical disease, FDG-PET findings increased physician confidence in disease assessment and reduced outlier assessments. The greatest variability in decisions regarding enrolment into trials was observed in vignettes representing constitutional symptoms alone and elevated acute-phase reactants. In these cases, FDG-PET findings influenced decisions about enrolment and improved physician confidence. In multivariable models, FDG-PET findings were 1.29 times more strongly associated with enrolment decisions compared with levels of acute-phase reactants. In part two, incorporation of FDG-PET data significantly improved agreement about enrolment decisions between raters [inter-rater reliability (IRR) = 0.68 (95% CI 0.67, 0.69) to IRR = 0.88 (95% CI 0.87, 0.89); P < 0.01]. CONCLUSIONS: Incorporation of FDG-PET data into assessment of TAK influences decisions about enrolment of patients into trials, improves physician confidence about clinical assessment and could help reduce variability in study populations. Future trials in TAK should consider incorporating FDG-PET data into eligibility criteria.

Is the impact of biologic agents in enteropathic spondylitis different from other spondylitis? Real life data from the HUR-BIO Registry.

OBJECTIVES: To compare enteropathic spondylitis (ES) with psoriatic spondylitis (PS) and ankylosing spondylitis (AS), in patients on biological disease-modifying anti-rheumatic drug (bDMARD) treatment. METHODS: Patients who were enrolled in the HUR-BIO registry were included. ES patients were considered as the main study group; AS and PS patients were included as the control groups. ES was defined as patients with inflammatory bowel disease (IBD) having inflammatory back pain/spine symptoms plus radiological sacroiliitis. RESULTS: Sixty-four ES patients (46.9% female), 128 AS patients (39.1% female), and 92 PS patients (62% female) were analysed. Baseline erythrocyte sedimentation rate (ESR) was significantly higher in the ES group than in the AS group. Both the baseline ESR and C-reactive protein were also higher in the ES group compared with the PS group. Among the first bDMARD use, infliximab use was higher in the ES group than the other groups. There was a marginal significant difference between the SpA subgroups in the retention rates of the first bDMARDs (log-rank, p=0.059). Ulcerative colitis was a significant predictor for switching of bDMARDs in comparison to Crohn's disease. Regarding the treatment responses, no significant differences were relevant for the three groups in terms of 50% improvement of the initial Bath Ankylosing Spondylitis Disease Activity Index score, the Assessment of Spondyloarthritis International Society partial remission score, and 20% improvement of ASAS score. CONCLUSIONS: A large majority of enteropathic spondyloarthritis patients on bDMARD treatment had radiographic sacroiliitis. ES patients had distinctive features that distinguish them from AS and PS patients.

Comprehensive assessment and outcomes of patients with chronic periaortitis.

OBJECTIVES: Chronic periaortitis (CP) is a less known but more frequently diagnosed fibro-inflammatory disorder, but we know little about it and data regarding follow-up and outcome are still very limited. This study aims to identify the clinicopathologic, laboratory, and radiologic features, as well as outcomes of CP patients. METHODS: Patients with CP from HUVAC database were included in the study. CP was diagnosed based on compatible imaging findings and histopathological evaluation (if available), in addition to clinical findings. Demographics, laboratory, clinical, and imaging data were retrospectively reviewed from medical records. RESULTS: A total of 51 (male/female:37/14) patients were included in the study. Median (IQR) age was 63 (53-69) years and follow-up duration was 40 (4-60) months. 32 of the patients were IgG4-related CP. The most common form of CP in our cohort was idiopathic retroperitoneal fibrosis (82%), followed by inflammatory abdominal aortic aneurysms (12%) and peri-aneurysmal retroperitoneal fibrosis (8%). 8 (15.6%) patients had thoracic periaortitis and 16 (31.6%) venous involvement. Cyclophosphamide (CYC) combined with steroids was the most preferred treatment modality (43%), followed by rituximab (RTX) (31.3%). Follow-up imaging was done after a median (IQR) of 7(3-11) months, 30% of the patients were stable and 64.1% showed regression. A total of 18 (35.2%) had been taken off therapy at the last visit. CONCLUSIONS: Idiopathic retroperitoneal fibrosis was the most frequent presentation, whereas 15.6% of patients had thoracic involvement. Venous involvement was also not uncommon. Optimal time for follow-up imaging was determined as 6-9 months. Steroids along with CYC/RTX had a favourable outcome in the treatment of these patients.

Investigation of anterior segment structures of the eye in Behçet's disease using in vivo confocal microscopy.

PURPOSE: We sought to investigate alterations in the corneal subbasal nerve plexus and endothelium in patients with Behçet's disease (BD). METHODS: This cross-sectional study included 64 patients with BD and 30 age- and gender-matched healthy control subjects. Those with BD were classified as having ocular or non-ocular disease. All subjects underwent a corneal endothelial and subbasal nerve density evaluation using in vivo confocal microscopy (IVCM). The differences among groups were analyzed using the Kruskal-Wallis test followed by Dunn's multiple comparison procedure. RESULTS: The mean age of study participants was 35.7 ± 10.2 years (16-58) in the ocular BD group, 39.6 ± 14.9 years (11-66) in the non-ocular BD group, and 34.1 ± 11.2 years (21-55) in the control group. No statistical significance was found in terms of age (p = 0.259) or sex (p = 0.560) between groups. The mean endothelial cell density determined with IVCM was 2124.9 [Formula: see text] 417.4 cells/mm2 (1811-3275) in the ocular group and 2546 [Formula: see text] 335 cells/mm2 (1798-3280) in the control group (p = 0.000). In the ocular group, the mean density of the subbasal nerve plexus was significantly lower (p = 0.004), and nerve tortuosity was significantly higher (p = 0.002). CONCLUSIONS: Ocular BD could be responsible for changes in the corneal layers, especially endothelial and corneal nerve structures. Nerve density and tortuosity differences could be inflammatory indicators for BD.

Pleuroparenchymal fibroelastosis in systemic sclerosis-associated interstitial lung disease.

BACKGROUND: To explore the frequency and clinical associations of radiologic pleuroparenchymal fibroelastosis (PPFE) in patients with systemic sclerosis-associated interstitial lung disease (SSc-ILD). METHODS: In this single-center retrospective study, high resolution computed tomography (HRCT) images of 105 patients with SSc-ILD were examined for the presence of PPFE. Demographic, clinical, laboratory, and pulmonary function test (PFT) data of patients with and without PPFE were compared. RESULTS: PPFE was detected in 19 (18.1%) patients ('definite PPFE' in 13 and 'consistent with PPFE' in 6 patients). Patients with PPFE had higher age and longer disease duration than PPFE (-) patients (p < 0.05 for both). Radiologic usual interstitial pneumoniae (UIP) pattern was more frequent (26.3% vs. 4.7%, p = 0.01) and median force vital capacity (FVC) was lower in patients with PPFE (64% vs. 82%, p = 0.005). Spontaneous pneumothorax developed in one patient with PPFE. More deaths occured in PPFE (+) group during follow-up (31% vs. 11%, p = 0.04).

Is Takayasu's arteritis more severe in children?

OBJECTIVES: Takayasu's arteritis (TAK) is a chronic vasculitis, affecting predominantly the aorta and/or its major branches. The aim of this study was to compare the differences between childhood and adult onset TAK. METHODS: We retrospectively evaluated 179 TAK patients followed between August 2005 and July 2019. Demographic characteristics, laboratory features, disease activity, echocardiographic data at diagnosis and treatment regimens in the disease course were compared between the paediatric and adult onset patients. RESULTS: Twenty-five paediatric-onset (<18 years of age at diagnosis) and 154 adult-onset patients (≥18 years of age at diagnosis) were enrolled. The mean age at diagnosis for children and adults were 13.6±4 and 35.6±13, respectively. Paediatric onset TAK patients had more intense inflammation at the time of diagnosis reflected in their clinical findings. Acute phase reactants were high in all paediatric patients and significantly higher in patients with paediatric-onset TAK (p=0.006 and p=0.005, respectively). Abdominal predominant disease was more common in the paediatric group, in contrast, focal disease and aortic arch predominant disease were more common in the adult group. Ascending aortic dilatation, left ventricular hypertrophy and moderate-severe aortic insufficiency were more frequent in echocardiography findings of paediatric onset TAK patients. In comorbidities, hypertension was more common in paediatric TAK patients during follow-up, whereas cerebrovascular disease was more common in adult patients. CONCLUSIONS: Our paediatric onset TAK patients presented with a more severe inflammation and more widespread vascular involvement. Multicentre studies from different geographic areas are needed to verify our observation and understand the underlying causes.

In the era of disease-modifying antirheumatic drugs, how close are we to treating rheumatoid arthritis without the use of glucocorticoids?

We wanted to see how close we could get to our goal of treating rheumatoid arthritis (RA) without the use of glucocorticoids (GCs) in the disease-modifying antirheumatic drugs (DMARDs) era using real-life data. Established in 2017, the TReasure database is a web-based, prospective, observational cohort for Turkey. As of May 2019, there were 2,690 RA patients recorded as receiving biologic and targeted synthetic DMARDs (bDMARDs and tsDMARDs) therapy. At the start of the bDMARDs or tsDMARDs, patients with follow-up visits of at least 3 months were registered. At the time of registration and the last visit, doses of GCs were recorded and it was determined if the target dose of ≤ 7.5 mg was achieved. During registration and follow-up, 23.4% of the patients did not receive GCs and 76.5% of the patients received GCs at any time. GCs could be stopped after 59 (25-116) months in 28.4% of these patients, but 71.6% of patients were still using GC. The target GC dose could not be achieved in 18.2% of these patients (n = 352). The rate of continuing to use GC was significantly higher in women, in the elderly, those with rheumatoid factor (RF) positive, with higher Visual Analog Scale (VAS) pain and Disease Activity Score (DAS)-28. The initial GC dose of ≥ 7.5 mg/day was found to be crucial in not reaching the GC target dose (p < 0.001, OR 39.0 (24.1-63.2)). The initial GC dose of ≥ 7.5 mg/day, female gender, age, RF positivity, high DAS28, and VAS pain level were all highly related for GC continuation. Despite the use of DMARDs, our data revealed that we are still far from achieving our goal of treating RA without using steroids.

Efficacy, retention, and safety of tofacitinib in real-life: Hur-bio monocentric experience

Background/aim: To assess the real-life efficacy, retention rate, and safety data of tofacitinib in rheumatoid arthritis (RA) patients. Materials and methods: We analyzed all patients registered in the HURBIO database who received at least 1 dose of tofacitinib. Patients who received at least one dose were included in retention analysis; patients with at least 1 control visit were included in efficacy and safety analysis. Factors predicting good response at the last follow-up visit were analyzed by logistic regression analysis. Drug retention rates were calculated using the Kaplan­Meier method and predictors of drug retention were determined by Cox proportional hazard model. Adverse events, reasons for switching, and discontinuation were also determined. Results: Two hundred and forty-seven (210, 85.0% female) patients were included in the study. The median duration of tofacitinib treatment was 10.2 (20.2) [med, (IQR)] months. Two hundred and four (82.6%) patients were included in safety and efficacy analysis; 45.6% of patients were in low-disease activity (LDA) state (DAS28-CRP ≤ 3.2). Predictors of LDA were being biologic-naïve [aOR 2.53 (1.31­4.88); 95% CI] and RF negativity [aOR 2.14 (1.12­4.07); 95% CI]. At 1 year, the overall tofacitinib retention rate was 63.9% with no relevant predicting factor. Response and retention rates of tofacitinib were similar in patients with and without concomitant csDMARDs. Treatment failure was the most common cause of discontinuation. The most common infectious and laboratory adverse events were herpes zoster infection (3.9 per 100 patient-years) and elevation in ALT (x3UNL: 9.7 per 100 patient-years), respectively. Conclusion: Tofacitinib is effective as monotherapy or in combination with csDMARDs. It is a well-tolerated treatment option in Turkish RA patients.

Management of Behcet's syndrome.

Behcet's syndrome (BS) is a variable vessel vasculitis with heterogeneous clinical features. Skin, mucosa and joint involvement can cause impairment of quality of life but do not cause permanent damage whereas untreated eye, vascular, nervous system and gastrointestinal system involvement can cause serious damage and even death. Management of BS as a multidisciplinary team enables a faster and more accurate diagnosis and well-integrated treatment strategies. Corticosteroids are the mainstay of therapy. Colchicine, AZA, ciclosporin-A, cyclophosphamide, IFN alpha, and tumour necrosis factor alpha inhibitors are other agents used as induction and/or maintenance therapy. Although biologic agents have been increasingly used, there are still unmet needs. Head-to-head comparison studies of some therapeutic options (e.g. TNF inhibitors vs IFN alpha in uveitis) are required. Novel therapeutic agents in the pipeline could change the standard of care for BS in the future.

The clinical features and outcomes of Turkish patients with IgG4-related disease:a single-center experience

Background/aim: Since the majority of the IgG4-related disease (IgG4-RD) patients in the literature are from the Far East and the United States, there is a lack of large series from other parts of the world. We aimed to identify the clinical characteristics and outcome of Turkish IgG4-RD patients from a tertiary center. Materials and methods: Fifty-two patients classified as having definite IgG4-RD according to comprehensive diagnostic criteria were included in the study. Patients not fulfilling the definite criteria due to lack of pathologic specimen and/or serum IgG4 levels were excluded (n = 47). Clinical, laboratory, and histopathological features and treatment approaches were analyzed. Results: Median age at diagnosis was 51.1 years and sex predominance was not observed (male/female: 26/26). Median follow-up duration was 18 (IQR 25­75: 8­35) months. Retroperitoneal fibrosis was the most frequent presentation. Twenty-four (46.1%) patients had localized involvement. Corticosteroids were the mainstay of treatment (92.5%). Rituximab had been used for cases resistant to previous treatment or with relapses in 19 (47.5%) patients. A complete response was achieved in 52.5% and partial response (<50% regression) in 40%. Conclusion: This large and first cohort of IgG4-RD patients from Turkey showed similar clinical features to European cohorts, except for the male predominance in previous cohorts. Corticosteroids and rituximab are effective in IgG4-RD but there is still uncertainty about the usage of corticosteroid-sparing agents.

Development of the Takayasu Arteritis Integrated Disease Activity Index.

OBJECTIVE: Accurate clinical assessment of disease activity in Takayasu arteritis (TAK) can be challenging. 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) can directly measure vascular inflammation. This study details the development of a new type of disease activity index called the Takayasu's Arteritis Integrated Disease Activity Index (TAIDAI). METHODS: Clinical symptoms for TAIDAI were identified from a literature review. Each symptom was paired with FDG-PET findings in corresponding arterial territories. Constitutional symptoms were paired with acute phase reactant levels. One point was given for each clinical symptom paired with supporting FDG-PET or laboratory abnormalities and summed into the TAIDAI score. A TAIDAI of ≥1 defined active disease. To assess performance of TAIDAI, face validity, content validity, and sensitivity to change were evaluated within a prospective observational cohort study of patients with TAK. RESULTS: Seventeen clinical symptoms were paired with imaging or laboratory abnormalities. In a cohort of 96 patients contributing 204 study visits, TAIDAI showed excellent sensitivity (96.3%) and good specificity (79.2%) compared to physician's clinical assessment. TAIDAI significantly correlated with physician global assessment, PET Vascular Activity Score, patient global assessment, and acute phase reactant levels. In patients treated with either tumor necrosis factor inhibitors or tocilizumab, a TAIDAI of 0 was achieved in 21 (91%) of 23 patients who met a predefined definition of clinical response. CONCLUSION: TAIDAI is new type of disease activity index in TAK in which clinical symptoms are integrated with specific laboratory and imaging findings. TAIDAI should be validated in future randomized controlled trials in TAK.

Clinical Characteristics and Outcomes of Polyarteritis Nodosa: An International Study.

OBJECTIVE: We describe the demographics, clinical features, disease course, and survival of polyarteritis nodosa (PAN) through an international collaboration (GLOBAL-PAN). METHODS: Patients with PAN were recruited between 1990 and 2020 from observational cohorts of nine countries across Europe, Japan, and North America. Eligibility was retrospectively defined using the European Medicines Agency classification algorithm. Patients with PAN related to hepatitis B virus (n = 12) and two monogenic diseases mimicking PAN, deficiency of adenosine deaminase 2 enzyme (n = 16) or familial Mediterranean fever (n = 11), were excluded. Data regarding organ involvement, relapse, disease-related damage, and survival were analyzed. RESULTS: Three hundred fifty-eight patients (female:male ratio 174:184), including those with systemic PAN (sPAN, n = 282) and cutaneous PAN (n = 76), were included. Twenty-five were pediatric onset. Mean ± SD age at diagnosis was 44.3 ± 18.1 years. Constitutional symptoms (71.5%), cutaneous involvement (70.5%), musculoskeletal findings (69.1%), and neurologic features (48.0%) were common manifestations. Among patients with sPAN, gastrointestinal involvement and proteinuria over 400 mg/day were reported in 52.2% and 11.2%, respectively. During a median (interquartile range) 59.6 (99.5) months of follow-up, relapse occurred in 48.5% of patients. One, 5- and 10-year survival rates for sPAN were 97.1%, 94.0%, and 89.0%, respectively. Predictors of death for sPAN included age ≥65 years at diagnosis, serum creatinine at diagnosis >140 µmol/L, gastrointestinal manifestations, and central nervous system (CNS) involvement. CONCLUSION: The spectrum of PAN remains a complex, multifaceted disease. Relapse is common. Age ≥65 years and serum creatinine >140 µmol/L at diagnosis, as well as gastrointestinal and CNS involvement, are independent predictors of death in sPAN.

Unveiling cancer risk in ANCA-associated vasculitis: result from the Turkish Vasculitis Study Group (TRVaS).

To investigate cancer incidence in patients with ANCA-associated vasculitis (AAV), compare it with the age/sex-specific cancer risk of the Turkish population, and explore independent risk factors associated with cancer. This multicenter, incidence case-control study was conducted using the TRVaS registry. AAV patients without cancer history before AAV diagnosis were included. Demographic and AAV-related data of patients with and without an incident cancer were compared. Standardized cancer incidence rates were calculated using age-/sex-specific 2017 Turkish National Cancer Registry data for cancers (excluding non-melanoma skin cancers). Cox regression was performed to find factors related to incident cancers in AAV patients. Of 461 AAV patients (236 [51.2%] male), 19 had incident cancers after 2022.8 patient-years follow-up. Median (IQR) disease duration was 3.4 (5.5) years, and 58 (12.6%) patients died [7 with cancer and one without cancer (log-rank, p = 0.04)]. Cancer-diagnosed patients were older, mostly male, and more likely to have anti-PR3-ANCA positivity. The cumulative cyclophosphamide dose was similar in patients with and without cancer. Overall cancer risk in AAV was 2.1 (SIR) ((1.3-3.2), p = 0.004); lung and head-neck [primary target sites for AAV] cancers were the most common. In Cox regression, male sex and ≥ 60 years of age at AAV diagnosis were associated with increased cancer risk, while receiving rituximab was associated with decreased cancer risk. Cancer risk was 2.1 times higher in AAV patients than the age-/sex-specific cancer risk of the Turkish population population, despite a high rate of rituximab use and lower dose of cyclophosphamide doses. Vigilance in cancer screening for AAV patients covering lung, genitourinary, and head-neck regions, particularly in males and the elderly, is vital.

IgG4-related pachymeningitis-Long term follow up and outcome of six patients.

OBJECTIVE: Our understanding of IgG4-RD and pachymeningitis has grown substantially, but the optimal approach for diagnosis, management, and long-term outcomes is still an area of uncertainty. METHODS: HUVAC is a database for IgG4-RD patients, this database was retrospectively evaluated for pachymeningeal disease. Demographic, clinical, serological, imaging, histopathological data, and treatment details were re-interpreted in patients with pachymeningitis. RESULTS: Among 97 patients with IgG4-RD, 6 (6.2%) had pachymeningitis. None of these patients had extracranial features, and also, in most of the patients, serum IgG4 levels were normal. Tentorium cerebelli and transverse sinus dura were the most commonly involved in the posterior fossa. During 18 months of median follow-up on steroid+-rituximab, none of them relapsed as pachymeningitis. CONCLUSION: Our patients were mainly older males with sole neurological involvement. Non-specific headache was the most common manifestation, and serum IgG4 levels were not useful for diagnosis. Typical radiology and tentorial thickening should suggest IgG4-RD and prompt an early biopsy. Moreover, accompanying hypophysitis could also be a clue. With steroids+ rituximab treatment, no relapse related to meningeal involvement was seen in long-term follow-up.