Tocilizumab use in giant cell arteritis: comparing Pharmaceutical Benefits Scheme eligible and ineligible cases in South Australia.

Tocilizumab (TCZ) is increasingly used as a steroid-sparing agent in giant cell arteritis (GCA), but there are strict Pharmaceutical Benefits Scheme (PBS) restrictions for its use in Australia. Patients who do not meet the PBS criteria can obtain TCZ through public hospital individual patient use (IPU) schemes which may not be universally accessible. We compared patients receiving IPU-approved TCZ with patients receiving PBS-subsidised TCZ and found IPU approvals were granted mainly for visual loss, a serious complication of GCA, in patients who otherwise failed to meet PBS criteria. Further studies demonstrating that TCZ is comparatively more effective than prednisolone monotherapy, as well as cost-effective, are needed to substantiate the rationale for expanding PBS approval criteria.

Antiplatelet therapy to prevent ischemic events in giant cell arteritis: protocol for a systematic review and meta-analysis.

BACKGROUND: Giant cell arteritis (GCA) is the most common systemic vasculitis in adults. Presenting features include new-onset headaches, constitutional symptoms, jaw claudication, polymyalgia rheumatica, and visual symptoms. Arterial inflammation with subsequent stenosis and occlusion may cause tissue ischemia, leading to blindness, strokes, and myocardial infarction. Oral antiplatelet therapy has been hypothesized to reduce GCA-related ischemic events. However, previous studies have demonstrated conflicting results regarding the efficacy of antiplatelet agents in GCA. The objective of this systematic review is to assess the safety and efficacy of antiplatelet therapy for the prevention of these events in adults with giant cell arteritis. METHODS: In this systematic review, we will include randomized controlled trials (RTCs), quasi-randomized trials, non-randomized intervention studies, cohort studies, and case-control studies on patients with new-onset or relapsing GCA. The intervention of interest will be pre-existing use or initiation of an oral antiplatelet medication (aspirin, clopidogrel, prasugrel, or ticagrelor) at GCA onset or relapse. The comparator of interest will be the absence of antiplatelet therapy. Endpoints will be evaluated after 6 and 12 months of follow-up. The primary outcome will be GCA-related ischemic events, including permanent blindness, stroke, myocardial infarction, and ischemic event-related deaths. Adverse events such as major bleeding and death caused by a bleeding event will be assessed. DISCUSSION: GCA-related ischemic events are catastrophic, sudden, often irreversible, and lead to significant morbidity. Antiplatelet agents are affordable, accessible, and could be effective for the prevention of these events. Nevertheless, the potential benefits of platelet aggregation inhibition must be weighed against their associated risk of bleeding. Assessing the efficacy and safety of antiplatelet therapy in GCA is therefore clinically important. SYSTEMATIC REVIEW REGISTRATION: Our systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO, registration number CRD42023441574.

Serum leukemia inhibitory factor (LIF) levels in patients with Takayasu's and Giant cell arteritis: A cross-sectional study.

INTRODUCTION AND OBJECTIVES: In this study, we aimed to evaluate LIF levels and its possible relationship with disease activity in patients with Takayasu's (TAK) and Giant cell arteritis (GCA) patients. MATERIALS AND METHODS: 23 Takayasu's arteritis, 9 Giant cell arteritis patients and 25 healthy volunteers were included in the study. Serum LIF levels were measured ELISA. RESULTS: The mean age of Giant cell arteritis patients was statistically significantly higher than the other groups (p<0.001). The rate of women was found to be higher in Takayasu's arteritis (p=0.021). When healthy control, patients with GCA and Takayasu arteritis were compared, there was a difference in LIF values (p=0.018). In subgroup analyzes, LIF values were found to be higher in GCA patients compared to healthy controls (p<0.05). There was no statistically significant correlation between LIF and CRP (Rho=-0.038, p=0.778), ESR (Rho=0.114, p=0.399) and ITAS (Rho=-0.357, p=0.094). While CRP was statistically significantly higher in patients with disease activity (p=0.003), there was no statistically significant difference between patients in terms of ESR and LIF values. While there was a statistically significant relationship between CRP (OR=1.19 [1.03-1.37], p=0.018) and disease activity in univariate analyses, no statistically significant variable was found in multivariable analyses. CONCLUSIONS: LIF values were significantly higher in patients with Giant cell arteritis compared to healthy controls.

Identification of two autoantigens recognised by circulating autoantibodies as potential biomarkers for diagnosing giant cell arteritis.

OBJECTIVES: Giant cell arteritis (GCA) is a common vasculitis affecting patients aged 50 and older. GCA leads to chronic inflammation of large/medium-sized vessel walls with complications such as permanent vision loss and risk of stroke and aortic aneurysms. Early diagnosis is crucial and relies on temporal artery biopsy (TAB) and ultrasound imaging of temporal and axillary arteries. However, these methods have limitations. Serum biomarkers as autoantibodies have been reported but with inconclusive data for their use in the clinical setting. Additionally, C-reactive protein and erythrocyte sedimentation rate are non-specific and limited in reflecting disease activity, particularly in patients treated with IL-6 inhibitors. This study aimed to identify serum autoantibodies as new diagnostic biomarkers for GCA using a human protein array. METHODS: One commercial and one proprietary human protein array were used for antibody profiling of sera from patients with GCA (n=55), Takayasu (TAK n=7), and Healthy Controls (HC n=28). The identified candidate autoantigens were purified and tested for specific autoantibodies by ELISA. RESULTS: Antibodies against two proteins, VSIG10L (V-Set and Immunoglobulin Domain Containing 10 Like) and DCBLD1 (discoidin), were identified and found to be associated with GCA, with an overall prevalence of 43-57%, respectively, and high specificity as individual antibodies. A control series of TAK sera tested negative. CONCLUSIONS: Detecting GCA-specific autoantibodies may offer a new, non-invasive tool for improving our diagnostic power in GCA. Even though cell-mediated immune responses are crucial for GCA pathogenesis, this finding opens the way for investigating the additional role of humoral immune responses in the disease.

Effectiveness of janus kinase inhibitors in relapsing giant cell arteritis in real-world clinical practice and review of the literature.

BACKGROUND: A substantial proportion of patients with giant cell arteritis (GCA) relapse despite standard therapy with glucocorticoids, methotrexate and tocilizumab. The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signalling pathway is involved in the pathogenesis of GCA and JAK inhibitors (JAKi) could be a therapeutic alternative. We evaluated the effectiveness of JAKi in relapsing GCA patients in a real-world setting and reviewed available literature. METHODS: Retrospective analysis of GCA patients treated with JAKi for relapsing disease at thirteen centers in Spain and one center in United States (01/2017-12/2022). Outcomes assessed included clinical remission, complete remission and safety. Clinical remission was defined as the absence of GCA signs and symptoms regardless of the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) values. Complete remission was defined as the absence of GCA signs and symptoms along with normal ESR and CRP values. A systematic literature search for other JAKi-treated GCA cases was conducted. RESULTS: Thirty-five patients (86% females, mean age 72.3) with relapsing GCA received JAKi therapy (baricitinib, n = 15; tofacitinib, n = 10; upadacitinib, n = 10). Before JAKi therapy, 22 (63%) patients had received conventional synthetic immunosuppressants (e.g., methotrexate), and 30 (86%) biologics (e.g., tocilizumab). After a median (IQR) follow-up of 11 (6-15.5) months, 20 (57%) patients achieved and maintained clinical remission, 16 (46%) patients achieved and maintained complete remission, and 15 (43%) patients discontinued the initial JAKi due to relapse (n = 11 [31%]) or serious adverse events (n = 4 [11%]). A literature search identified another 36 JAKi-treated GCA cases with clinical improvement reported for the majority of them. CONCLUSIONS: This real-world analysis and literature review suggest that JAKi could be effective in GCA, including in patients failing established glucocorticoid-sparing therapies such as tocilizumab and methotrexate. A phase III randomized controlled trial of upadacitinib is currently ongoing (ClinicalTrials.gov ID NCT03725202).

Evaluation of the extracranial "multifocal arcuate sign," a novel MRI finding for the diagnosis of giant cell arteritis, on STIR and contrast-enhanced T1-weighted images.

BACKGROUND: While early diagnosis of giant cell arteritis (GCA) based on clinical criteria and contrast-enhanced MRI findings can lead to early treatment and prevention of blindness and cerebrovascular accidents, previously reported diagnostic methods which utilize contrast-enhanced whole head images are cumbersome. Diagnostic delay is common as patients may not be aware of initial symptoms and their significance. To improve current diagnostic capabilities, new MRI-based diagnostic criteria need to be established. This study aimed to evaluate the "multifocal arcuate sign" on short tau inversion recovery (STIR) and contrast-enhanced T1-weighted (CE-T1W) images as a novel extracranial finding for the diagnosis of GCA. METHODS: A total of 17 consecutive patients (including five with GCA) who underwent CE-T1W and whole-brain axial STIR imaging simultaneously between June 2010 and April 2020 were enrolled. We retrospectively reviewed their MR images. The "multifocal arcuate sign" was defined as "multiple distant arcuate areas with high signal intensity in extracranial soft tissues such as subcutaneous fat, muscles, and tendons." Extracranial abnormal high-signal-intensity areas were classified as "None," when no lesions were detected; "Monofocal," when lesions were detected only in one place; and "Multifocal," when lesions were detected in multiple places. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of "Multifocal" areas were calculated using cross tabulation. Fisher's exact test was used to compare "Multifocal" areas in five patients with GCA and those with other diseases. In addition, mean Cohen's kappa and Fleiss' kappa statistics were used to compare inter-reader agreement. RESULTS: The sensitivity, specificity, PPV, and NPV of the "multifocal arcuate sign" in patients with GCA were 60%, 92-100%, 75-100%, and 85-86%, respectively. Significantly more patients with GCA had "Multifocal" areas compared to those with other diseases (Fisher's exact test, p = 0.008-0.027). Mean Cohen's kappa and Fleiss' kappa for inter-reader agreement with respect to the five GCA patients were 0.52 and 0.49, respectively, for both STIR and CE-T1W sequences. CONCLUSIONS: The new radiologic finding of "multifocal arcuate sign" on STIR and CE-T1W images may be used as a radiologic criterion for the diagnosis of GCA, which can make plain MRI a promising diagnostic modality.

Updates in the Management of Giant Cell Arteritis.

PURPOSE OF THE REVIEW: To briefly review the latest updates in management in giant cell arteritis, an autoimmune vasculitis affecting the medium to large vessels. RECENT FINDINGS: Here, we review the known and newer trends in management of giant cell arteritis. While high dose glucocorticoids remain the mainstay of therapy, immunosuppressive medications are increasingly utilized to reduce the burden and risk of long-term glucocorticoid use. Published guidelines by the American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) suggest early use of steroid-sparing immunosuppressive medications in patients with recently diagnosed or relapsing giant cell arteritis. Immunosuppressive medications include oral small molecules such as methotrexate and leflunomide and biologics, including the recently Federal Drug Administration (FDA) approved tocilizumab. Glucocorticoids remain the cornerstone of management for newly diagnosed disease but with the increasing use of medications such as IL-6 inhibitors, patients are decreasing steroid use within weeks, thereby limiting risks associated with long-term steroid use.

Cranial and extracranial manifestations of giant cell arteritis: a single-center observational study.

INTRODUCTION: Giant cell arteritis (GCA) presents two major phenotypes - cranial (cGCA) and extracranial (exGCA). exGCA may be overlooked. The study aimed to compare the clinical characteristics between cGCA and exGCA. METHODS: Electronic medical records of patients treated between January 2015 and July 2023 at the Department of Rheumatology were searched for the diagnosis of GCA. The clinical characteristics of patients with cGCA, exGCA, and overlapping GCA manifestations were compared. RESULTS: Out of 32 patients with GCA, 20 had cGCA, 7 had exGCA, and 5 had overlap manifestations. The groups did not differ significantly in demographics, clinical signs/symptoms, or laboratory test results. Importantly, the combined group of patients with exGCA and overlap GCA had a statistically significant delay in initiating treatment (median 12 weeks) compared to patients with cGCA (median 4 weeks; p = 0.008). CONCLUSION: Our study confirmed the insidious nature of exGCA, which lacks distinctive clinical symptoms and consequently leads to delayed treatment.

Decoding CD4+ T cell transcriptome in giant cell arteritis: Novel pathways and altered cross-talk with monocytes.

BACKGROUND: Giant cell arteritis (GCA) is an immune-mediated large-vessels vasculitis with complex etiology. Although the pathogenic mechanisms remain poorly understood, a central role for CD4+ T cells has been demonstrated. In this context, understanding the transcriptome dysregulation in GCA CD4+ T cells will yield new insights into its pathogenesis. METHODS: Transcriptome analysis was conducted on CD4+ T cells from 70 patients with GCA with different disease activity and treatment status (active patients before treatment and patients in remission with and without glucocorticoid treatment), and 28 healthy controls. The study also evaluated potential impacts of DNA methylation on gene expression alterations and assessed cross-talk with CD14+ monocytes. RESULTS: This study has uncovered a substantial number of genes and pathways potentially contributing to the pathogenicity of CD4+ T cells in GCA. Specifically, CD4+ T cells from GCA patients with active disease exhibited altered expression levels of genes involved in multiple immune-related processes, including various interleukins (IL) signaling pathways. Notably, IL-2, a decisive interleukin for regulatory T cells homeostasis, was among the most significant. Additionally, impaired apoptotic pathways appear crucial in GCA development. Our findings also suggest that histone-related epigenetic pathways may be implicated in promoting an inflammatory phenotype in GCA active patients. Finally, our study observed altered signaling communication, such as the Jagged-Notch signaling, between CD4+ T cells and monocytes that could have pathogenic relevance in GCA. CONCLUSIONS: Our study suggests the participation of novel cytokines and pathways and the occurrence of a disruption of monocyte-T cell crosstalk driving GCA pathogenesis.

Polymyalgia rheumatica shows metabolomic alterations that are further altered by glucocorticoid treatment: Identification of metabolic correlates of fatigue.

OBJECTIVE: In polymyalgia rheumatica (PMR), glucocorticoids (GCs) relieve pain and stiffness, but fatigue may persist. We aimed to explore the effect of disease, GCs and PMR symptoms in the metabolite signatures of peripheral blood from patients with PMR or the related disease, giant cell arteritis (GCA). METHODS: Nuclear magnetic resonance spectroscopy was performed on serum from 40 patients with untreated PMR, 84 with new-onset confirmed GCA, and 53 with suspected GCA who later were clinically confirmed non-GCA, and 39 age-matched controls. Further samples from PMR patients were taken one and six months into glucocorticoid therapy to explore relationship of metabolites to persistent fatigue. 100 metabolites were identified using Chenomx and statistical analysis performed in SIMCA-P to examine the relationship between metabolic profiles and, disease, GC treatment or symptoms. RESULTS: The metabolite signature of patients with PMR and GCA differed from that of age-matched non-inflammatory controls (R2 > 0.7). There was a smaller separation between patients with clinically confirmed GCA and those with suspected GCA who later were clinically confirmed non-GCA (R2 = 0.135). In PMR, metabolite signatures were further altered with glucocorticoid treatment (R2 = 0.42) but did not return to that seen in controls. Metabolites correlated with CRP, pain, stiffness, and fatigue (R2 ≥ 0.39). CRP, pain, and stiffness declined with treatment and were associated with 3-hydroxybutyrate and acetoacetate, but fatigue did not. Metabolites differentiated patients with high and low fatigue both before and after treatment (R2 > 0.9). Low serum glutamine was predictive of high fatigue at both time points (0.79-fold change). CONCLUSION: PMR and GCA alter the metabolite signature. In PMR, this is further altered by glucocorticoid therapy. Treatment-induced metabolite changes were linked to measures of inflammation (CRP, pain and stiffness), but not to fatigue. Furthermore, metabolite signatures distinguished patients with high or low fatigue.

Risk loci involved in giant cell arteritis susceptibility: a genome-wide association study.

BACKGROUND: Giant cell arteritis is an age-related vasculitis that mainly affects the aorta and its branches in individuals aged 50 years and older. Current options for diagnosis and treatment are scarce, highlighting the need to better understand its underlying pathogenesis. Genome-wide association studies (GWAS) have emerged as a powerful tool for unravelling the pathogenic mechanisms involved in complex diseases. We aimed to characterise the genetic basis of giant cell arteritis by performing the largest GWAS of this vasculitis to date and to assess the functional consequences and clinical implications of identified risk loci. METHODS: We collected and meta-analysed genomic data from patients with giant cell arteritis and healthy controls of European ancestry from ten cohorts across Europe and North America. Eligible patients required confirmation of giant cell arteritis diagnosis by positive temporal artery biopsy, positive temporal artery doppler ultrasonography, or imaging techniques confirming large-vessel vasculitis. We assessed the functional consequences of loci associated with giant cell arteritis using cell enrichment analysis, fine-mapping, and causal gene prioritisation. We also performed a drug repurposing analysis and developed a polygenic risk score to explore the clinical implications of our findings. FINDINGS: We included a total of 3498 patients with giant cell arteritis and 15 550 controls. We identified three novel loci associated with risk of giant cell arteritis. Two loci, MFGE8 (rs8029053; p=4·96 × 10-8; OR 1·19 [95% CI 1·12-1·26]) and VTN (rs704; p=2·75 × 10-9; OR 0·84 [0·79-0·89]), were related to angiogenesis pathways and the third locus, CCDC25 (rs11782624; p=1·28 × 10-8; OR 1·18 [1·12-1·25]), was related to neutrophil extracellular traps (NETs). We also found an association between this vasculitis and HLA region and PLG. Variants associated with giant cell arteritis seemed to fulfil a specific regulatory role in crucial immune cell types. Furthermore, we identified several drugs that could represent promising candidates for treatment of this disease. The polygenic risk score model was able to identify individuals at increased risk of developing giant cell arteritis (90th percentile OR 2·87 [95% CI 2·15-3·82]; p=1·73 × 10-13). INTERPRETATION: We have found several additional loci associated with giant cell arteritis, highlighting the crucial role of angiogenesis in disease susceptibility. Our study represents a step forward in the translation of genomic findings to clinical practice in giant cell arteritis, proposing new treatments and a method to measure genetic predisposition to this vasculitis. FUNDING: Institute of Health Carlos III, Spanish Ministry of Science and Innovation, UK Medical Research Council, and National Institute for Health and Care Research.

Outcome and prognosis of isolated carotid vasculitis.

OBJECTIVE: To assess the prognosis and outcome of patients with isolated carotid vasculitis. METHODS: We performed a retrospective multicenter study of 36 patients (median age at diagnosis was 37 [IQR 27-45] years and 11 [31 %] patients were men) with initial presentation as isolated carotid vasculitis. Study endpoints included vascular complications, relapses, and progression to large vessel vasculitis (i.e. Giant cell arteritis or Takayasu). RESULTS: The most frequent involvement was the left internal carotid artery (39 %), and 81 % had stenosis. After a median follow-up of 32 months [IQR 12-96], 21 (58 %) patients had a vascular event, including 31 % of new onset vascular lesions and 25 % of stroke/transient ischemic attack. Patients with stroke had less carotidynia at diagnosis (33 % vs 74 %, p = 0.046), higher significant carotid stenosis (i.e. > 50 %) (89 % vs. 30 %, p = 0.026) and higher severe carotid stenosis (i.e. >70 %) (67 % vs 19 %, p = 0.012), compared to those without stroke. Twenty (52 %) patients experienced relapses. High CRP at diagnosis was associated with relapses (p = 0.022). At the end of follow-up, 21 (58 %) patients were classified as having Takayasu arteritis, 13 (36 %) as isolated carotid vasculitis, and two (6 %) as giant cell arteritis. CONCLUSION: Carotid vasculitis may occur as a topographically limited lesion and is associated with significant rate of vascular complications.

Diagnostic Strategy Using Color Doppler Ultrasound of Temporal Arteries in Patients With High Clinical Suspicion of Giant Cell Arteritis : A Prospective Cohort Study.

BACKGROUND: Giant cell arteritis (GCA) is the most prevalent systemic vasculitis in people older than 50 years. Any delay in diagnosis impairs patients' quality of life and can lead to permanent damage, particularly vision loss. OBJECTIVE: To evaluate a diagnostic strategy for GCA using color Doppler ultrasound of the temporal artery as a first-line diagnostic test, temporal artery biopsy (TAB) as a secondary test, and physician expertise as the reference method. DESIGN: Prospective multicenter study with a 2-year follow-up. (ClinicalTrials.gov: NCT02703922). SETTING: Patients were referred by their general practitioner or ophthalmologist to a physician with extensive experience in GCA diagnosis and management in one of the participating centers: 4 general and 2 university hospitals. PATIENTS: 165 patients with high clinical suspicion of GCA, aged 79 years (IQR, 73 to 85 years). INTERVENTION: The diagnostic procedure was ultrasound, performed less than 7 days after initiation of corticosteroid therapy. Only ultrasound-negative patients underwent TAB. MEASUREMENTS: Bilateral temporal halo signs seen on ultrasound were considered positive. Ultrasound and TAB results were compared with physician-diagnosed GCA based on clinical findings and other imaging. RESULTS: Diagnosis of GCA was confirmed in 44%, 17%, and 21% of patients by ultrasound, TAB, and clinical expertise and/or other imaging tests, respectively. Their diagnosis remained unchanged at 1 month, and 2 years for those with available follow-up data. An alternative diagnosis was made in 18% of patients. The proportion of ultrasound-positive patients among patients with a clinical GCA diagnosis was 54% (95% CI, 45% to 62%). LIMITATION: Small sample size, no blinding of ultrasound and TAB results, lack of an objective gold-standard comparator, and single diagnostic strategy. CONCLUSION: By using ultrasound of the temporal arteries as a first-line diagnostic tool in patients with high clinical suspicion of GCA, further diagnostic tests for patients with positive ultrasound were avoided. PRIMARY FUNDING SOURCE: Tender "Recherche CH-CHU Poitou-Charentes 2014."

Evaluation of baseline F-18 FDG positron emission tomography in the diagnosis and assessment of giant cell arteritis.

Background/aim: The aim of this study is to evaluate the baseline F18-FDG PET/CT findings of individuals diagnosed with giant cell arteritis (GCA) and to explore its association with clinical findings and classification criteria. Materials and methods: We analysed data from patients who underwent F18-FDG PET/CT scans to investigate large vessel (LV) involvement between 2010 and 2019. Only patients with a clinical diagnosis of GCA and at least 6 months of follow-up were included. We compared initial clinical features and laboratory findings based on the presence of LV vasculitis on PET/CT and the maximum standard uptake value (SUVmax) of vascular territories. Results: Twenty-nine patients (median age at diagnosis: 70, F/M: 24/5) were included in the study. Among them, 21 patients (72.4%) presented with cranial symptoms, while 8 patients (27.5%) had isolated LV-GCA. Twenty-two patients (75.9%) met the ACR/EULAR 2022 GCA classification criteria. LV vasculitis was detected on PET/CT in 23 patients (79.3%). A positive correlation was observed between SUVmax in the thoracic aorta and both CRP and ESR levels (r = 0.50, p = 0.026 and r = 0.63, p = 0.002, respectively). PET/CT positive patients were found to be younger (p = 0.016) and more frequently female (p = 0.017). They also exhibited fewer headaches (56.5% vs. 100%, p = 0.04), experienced fewer flares during follow-up (p = 0.03), and had a lower cumulative glucocorticoid dose at the 6th month (p = 0.036). Comparison of PET/CT-positive patients (n = 23) based on the fulfilment of the ACR/EULAR 2022 classification criteria revealed that patients who met these criteria were older (p = 0.02) and had significantly lower CRP levels at diagnosis (p = 0.02). Conclusion: The performance of F18-FDG PET/CT in diagnosing LV involvement in GCA is favourable, and the severity of FDG uptake in the vessel wall correlates with the acute phase response. Patients with extracranial involvement on PET/CT exhibit distinct features, including a younger age and female predominance. Additionally, these patients appear to experience fewer relapses and require lower doses of glucocorticoids. However, the clinical significance of PET/CT in patients who met ACR/EULAR classification criteria, predominantly consisting of patients with ischemic cranial symptoms, could not be determined in our study.