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.

A multidisciplinary approach to reproductive healthcare in women with rheumatic disease.

INTRODUCTION: Rheumatic disease (RD) patients when family planning must consider fertility, disease activity, and management from preconception to lactation. A clear understanding is necessary, especially for those receiving disease-modifying antirheumatic medications. Previous studies have highlighted unmet needs in the care of women with RDs with reproductive healthcare needs. This study describes the first published standardized reproductive care pathway for women with RDs and the outcomes of this approach. MATERIAL AND METHODS: We developed the care pathway with multidisciplinary input from rheumatologists, rheumatology nurse specialists, obstetricians, midwives, maternal medicine specialists, and pharmacists. We identified patients' emotional and healthcare needs, ensured access to expert advice, maintenance of good disease control, and positive reproductive outcomes. We prospectively followed the patients and report the results of the service. RESULTS: Ninety-eight women with median age (range) of 35 years (19-48) were assessed. The majority had an inflammatory arthritis. Seventy-six babies were born to 62 mothers. There were 12 miscarriages and one perinatal death. Breastfeeding rates at 6 weeks were low (28%). CONCLUSION: We describe the first published evidence-based integrated multidisciplinary reproductive care pathway for women with RDs and the results of this approach. Seventy percent of women successful in trying to conceive delivered a healthy baby, and 90% of patients were 'very satisfied' with the service.

Interleukin-6 does not upregulate pro-inflammatory cytokine expression in an ex vivo model of giant cell arteritis.

OBJECTIVE: The aim of this study was to examine the pro-inflammatory effects of IL-6 in ex vivo temporal artery explant cultures. METHODS: Patients meeting 1990 ACR classification criteria for GCA were prospectively recruited. Temporal artery biopsies were obtained and temporal artery explants cultured ex vivo with IL-6 (10-40 ng/ml) in the presence or absence of its soluble receptor (sIL-6R; 20 ng/ml) for 24 h. Explant supernatants were harvested after 24 h and assayed for IFN-γ, TNF-α, Serum amyloid A, IL-1ß, IL-17, IL-8, angiotensin II and VEGF by ELISA. Myofibroblast outgrowths, cytoskeletal rearrangement and wound repair assays were performed. RESULTS: IL-6 augmented production of VEGF, but not of any of the other pro-inflammatory mediators assayed. No differences were observed in the explants cultured in the presence or absence of the sIL-6R or between those with a positive (n = 11) or negative (n = 17) temporal artery biopsy. IL-6 did not enhance myofibroblast proliferation or migration. Western blot analysis confirmed signalling activation, with increased expression of pSTAT3 in response to IL-6+sIL-6R. CONCLUSION: IL-6 stimulation of temporal artery explants from patients with GCA neither increased expression of key pro-inflammatory mediators nor influenced myofibroblast proliferation or migration.

Performance characteristics and predictors of temporal artery ultrasound for the diagnosis of giant cell arteritis in routine clinical practice in a prospective cohort.

OBJECTIVES: The diagnosis of giant cell arteritis (GCA) is primarily a clinical one. Temporal artery (TA) ultrasound (US) has been proposed as a new diagnostic tool. We aimed to assess the performance characteristics of TA US in routine clinical practice. METHODS: All patients presenting with suspected GCA to our institution are recruited to a prospective registry. Patients who had both a TA US and biopsy (TAB) performed at the time of presentation were included in the current study. The performance characteristics of TA US was compared to physician diagnosis at six months following presentation. Predictive factors for a positive TA US were explored in univariate and multivariable logistic regression analyses. RESULTS: 162 patients were included, 123 (76%) with GCA. Mean (SD) duration of glucocorticoid therapy was 6.6 days (19.4) at the time of TA US. TA US had a sensitivity of 52.8% (95%CI 43.7, 61.9) and specificity of 71.8% (95%CI 54.9, 84.5) for the diagnosis of GCA. Glucocorticoid duration did not significantly impact the results. A sequential strategy of TA US followed by TAB in the case of a negative US had a sensitivity of 78.9% (95%CI 70.1, 85.5) and specificity of 71.8% (95%CI 54.9, 84.5), equivalent to a simultaneous testing strategy. The only factor independently predictive of a positive TA US was male sex (OR 5.53, 95% CI 2.72 to 11.22, p<0.001). CONCLUSIONS: TA US is potentially useful in the diagnosis of GCA; however, interpretation of its results requires knowledge of the performance characteristics in the target population.

Updated pharmacological management of rheumatoid arthritis for women before, during, and after pregnancy, reflecting recent guidelines.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic immune-mediated inflammatory disease which can cause significant disability, morbidity, mortality, and impaired fertility. It commonly affects women of childbearing age. Managing rheumatoid arthritis (RA) in the perinatal period poses challenges. There is concern about the teratogenic effects of many traditional disease-modifying anti-rheumatic drugs (DMARDs) and an ever-growing list of new therapeutic options with limited data in pregnancy and breastfeeding. AIMS: We aimed to create a standardized approach to pharmacological management of RA patients seen in our newly established Rheumatology and Reproductive Health Service. METHODS: We reviewed relevant publications on the use of anti-rheumatic drugs in pregnancy. These include recent guidelines from The British Society for Rheumatology (BSR) and British Health Professionals in Rheumatology (BHPR) and the European League Against Rheumatism (EULAR). RESULTS: After considering relevant publications, we developed a Saint Vincent's University Hospital/National Maternity Hospital consensus protocol for evidence-based medication in pregnancy in RA. CONCLUSIONS: RA tends to improve during pregnancy and flare postpartum. Several anti-rheumatic medication options during pregnancy and breastfeeding are now available including anti-tumor necrosis factor (anti-TNF) agents. Good disease control at all stages of reproduction is important to ensure best outcome for both mother and baby.

Diagnostic Utility of Computed Tomographic Angiography in Giant-Cell Arteritis.

Background and Purpose- The diagnosis of giant-cell arteritis (GCA) is challenging. Superficial temporal artery biopsy and ultrasound are positive in only 50%. We evaluated computed tomographic angiography (CTA) of the head in GCA. Methods- This case-control study was performed using a prospective GCA registry. Cases presented with stroke symptoms, had a CTA, and were subsequently diagnosed with GCA. Age- and sex-matched controls presented with stroke symptoms, had a CTA, and were not diagnosed with GCA. CTAs were evaluated for the presence of superficial temporal artery abnormalities. Results- Fourteen cases met the inclusion criteria and were matched with 14 controls. Blurred vessel wall margins and perivascular enhancement was found in 10 cases (71.4%) and 2 controls (14.3%). CTA has an accuracy of 78.6%, sensitivity of 71.4%, and a specificity of 85.7% for GCA. Conclusions- CTA detects superficial temporal artery abnormalities in GCA. This may facilitate early diagnosis and prompt implementation of potentially sight-saving and stroke-preventing treatment.

IL-16/miR-125a axis controls neutrophil recruitment in pristane-induced lung inflammation.

Severe lung inflammation and alveolar hemorrhage can be life-threatening in systemic lupus erythematosus (SLE) patients if not treated early and aggressively. Neutrophil influx is the driver key of this pathology, but little is known regarding the molecular events regulating this recruitment. Here, we uncover a role for IL-16/mir-125a in this pathology and show not only that IL-16 is a target for miR-125a but that reduced miR-125a expression in SLE patients associates with lung involvement. Furthermore, in the pristane model of acute "SLE-like" lung inflammation and alveolar hemorrhage, we observed reduced pulmonary miR-125a and enhanced IL-16 expression. Neutrophil infiltration was markedly reduced in the peritoneal lavage of pristane-treated IL-16-deficient mice and elevated following i.n. delivery of IL-16. Moreover, a miR-125a mimic reduced pristane-induced IL-16 expression and neutrophil recruitment and rescued lung pathology. Mechanistically, IL-16 acts directly on the pulmonary epithelium and markedly enhances neutrophil chemoattractant expression both in vitro and in vivo, while the miR-125a mimic can prevent this. Our results reveal a role for miR-125a/IL-16 in regulating lung inflammation and suggest this axis may be a therapeutic target for management of acute lung injury in SLE.

Interleukin 12 and interleukin 23 play key pathogenic roles in inflammatory and proliferative pathways in giant cell arteritis.

OBJECTIVES: The pathogenesis of giant cell arteritis (GCA) remains unclear. TH1 and TH17 pathways are implicated, but the proximal initiators and effector cytokines are unknown. Our aim was to assess the role of interleukin 12 (IL-12) and interleukin 23 (IL-23) in GCA pathogenesis. METHODS: IL-12 and IL-23 expression were quantified by immunohistochemistry in temporal artery biopsies (TABs). Temporal artery (TA) explant, peripheral blood mononuclear cell (PBMC) and myofibroblast outgrowth culture models were established. PBMCs and TA explants were cultured for 24 hours in the presence or absence of IL-12 (50 ng/mL) or IL-23 (10 ng/mL). Gene expression in TA was quantified by real-time PCR and cytokine secretion by ELISA. Myofibroblast outgrowths were quantified following 28-day culture. RESULTS: Immunohistochemistry demonstrated increased expression of interleukin 12p35 (IL-12p35) and interleukin 23p19 (IL-23p19) in biopsy-positive TAs, localised to inflammatory cells. IL-12p35 TA expression was significantly increased in those with cranial ischaemic complications (p=0.026) and large vessel vasculitis (p=0.006). IL-23p19 TA expression was increased in those with two or more relapses (p=0.007). In PBMC cultures, exogenous IL-12 significantly increased interleukin 6 (IL-6) (p=0.009), interleukin 22 (IL-22) (p=0.003) and interferon γ (IFN-γ) (p=0.0001) and decreased interleukin 8 (IL-8) (p=0.0006) secretion, while exogenous IL-23 significantly increased IL-6 (p=0.029), IL-22 (p=0.001), interleukin 17A (IL-17A) (p=0.0003) and interleukin 17F (IL-17F) (p=0.012) secretion. In ex vivo TA explants, IL-23 significantly increased gene expression of IL-8 (p=0.0001) and CCL-20 (p=0.027) and protein expression of IL-6 (p=0.002) and IL-8 (p=0.004). IL-12 (p=0.0005) and IL-23 (p<0.0001) stimulation increased the quantity of myofibroblast outgrowths from TABs. CONCLUSION: IL-12 and IL-23 play central and distinct roles in stimulating inflammatory and proliferative pathways relevant to GCA pathogenesis.

Successful reconstruction of an ocular defect resulting from granulomatosis with polyangiitis, following treatment with rituximab.

PURPOSE: To report a unique case of orbital inflammatory disease which was ultimately diagnosed as granulomatosis with polyangitis (GPA) and thus successfully treated. OBSERVATION: A 47 year-old man presented with a rapidly progressive necrotic soft tissue mass within the medial antero-superior aspect of the right eyelid and orbit. He also had transient retinal vasculitis in the left. Serology, histology and imaging were atypical of, but consistent with, GPA. He was thus successfully treated with intravenous rituximab followed by reconstruction of the medial eyelid. CONCLUSION AND IMPORTANCE: A high index of suspicion of GPA is required in orbital inflammatory disease, especially when typical diagnostic findings are absent.

Ustekinumab for refractory giant cell arteritis: A prospective 52-week trial.

OBJECTIVES: Giant cell arteritis (GCA) is the most common form of systemic vasculitis. Glucocorticoids are an effective treatment but have significant adverse events and relapses are common. Interleukins 12 (IL-12) and 23 (IL-23) stimulate TH1 and TH17 responses and are implicated in the pathogenesis of GCA. The aim of this study was to evaluate the efficacy and safety of IL-12/23 blockade with ustekinumab in GCA. METHODS: We performed a prospective open label study of ustekinumab in patients with refractory GCA. Ustekinumab 90mg was administered subcutaneously every 12 weeks. The primary outcome was the comparison of the median glucocorticoid dose prior to commencement of ustekinumab and at 52 weeks. Secondary outcomes included physician assessed relapse, acute phase reactants, and imaging assessment of large vessel vasculitis (LVV). RESULTS: Twenty-five GCA patients received ustekinumab. All patients had failed to taper glucocorticoids despite addition of a median of 1 other immunosuppressive agent. At week 52, median (IQR) daily prednisolone dose decreased from 20 (15, 25)mg to 5 (2.5, 5)mg (p < 0.001). Six patients (24%) stopped prednisolone completely. No patient experienced a relapse of GCA while receiving ustekinumab. Median (IQR) CRP decreased significantly from 12.9 (5.3, 42) to 6 (2.6, 12.5)mg/L (p = 0.006). CT angiography demonstrated improvement of LVV in all patients studied. No unexpected adverse events were observed with ustekinumab. CONCLUSIONS: Ustekinumab may be effective for the treatment of GCA and warrants further assessment in a randomized controlled trial.

A Genome-wide Association Study Identifies Risk Alleles in Plasminogen and P4HA2 Associated with Giant Cell Arteritis.

Giant cell arteritis (GCA) is the most common form of vasculitis in individuals older than 50 years in Western countries. To shed light onto the genetic background influencing susceptibility for GCA, we performed a genome-wide association screening in a well-powered study cohort. After imputation, 1,844,133 genetic variants were analyzed in 2,134 case subjects and 9,125 unaffected individuals from ten independent populations of European ancestry. Our data confirmed HLA class II as the strongest associated region (independent signals: rs9268905, p = 1.94 × 10-54, per-allele OR = 1.79; and rs9275592, p = 1.14 × 10-40, OR = 2.08). Additionally, PLG and P4HA2 were identified as GCA risk genes at the genome-wide level of significance (rs4252134, p = 1.23 × 10-10, OR = 1.28; and rs128738, p = 4.60 × 10-9, OR = 1.32, respectively). Interestingly, we observed that the association peaks overlapped with different regulatory elements related to cell types and tissues involved in the pathophysiology of GCA. PLG and P4HA2 are involved in vascular remodelling and angiogenesis, suggesting a high relevance of these processes for the pathogenic mechanisms underlying this type of vasculitis.

The Risk of Progressive Multifocal Leukoencephalopathy in the Biologic Era: Prevention and Management.

Progressive multifocal leukoencephalopathy (PML) is a rare, typically fatal, demyelinating central nervous system infection caused by reactivation of the John Cunningham virus that generally occurs in immunosuppressed patients. With an evolving understanding of a greater clinical heterogeneity of PML and significant implications for therapy, PML should be considered in the differential diagnosis of neurologic presentations of rheumatic diseases. Increased awareness of PML among rheumatologists is required, as earlier diagnosis and restoration of immune function may improve the otherwise grim prognosis associated with PML.

The role of toll like receptors in giant cell arteritis.

GCA is a common primary systemic vasculitis that results in granulomatous inflammation of medium to large arteries. Both innate and adaptive immune mechanisms combine to drive intimal hyperplasia, luminal stenosis and ultimately occlusion. While the pathogenesis of GCA is incompletely understood, the activation of resident adventitial dendritic cells via toll like receptors (TLRs) appears to be a crucial inciting event. Here we explore the role of TLRs in the pathogenesis of GCA, including their effects on dendritic cell and T cell activation and recruitment, putative infectious triggers for GCA and the potential of TLR inhibition as a novel therapeutic strategy in GCA.

Plasma fibrinogen along with patient-reported outcome measures enhances management of polymyalgia rheumatica: a prospective study.

OBJECTIVE: We sought to prospectively examine the responsiveness of a number of patient-reported outcome (PRO) measures in polymyalgia rheumatica (PMR), as well as their relationship to the biomarkers erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and plasma fibrinogen. METHODS: Sixty patients with PMR were divided into active (n = 25) or inactive (n = 35) disease groups based on symptoms; physician assessment; and the biomarkers ESR, CRP, and plasma fibrinogen. Groups underwent assessment at baseline and 6 weeks. Disease activity measures and relevant PRO measures were recorded. Measures of responsiveness were compared for all PRO and biomarkers. RESULTS: Visual analog scale disease activity (VASDA) and VAS quality of life (VASQOL) are more responsive to change in disease activity than VAS pain, morning stiffness, Health Assessment Questionnaire (HAQ), and PMR-activity score (AS). Analysis of PMR-AS versus VASDA, VASQOL, and HAQ showed correlation coefficients of 0.87 (p < 0.001), 0.80 (p < 0.001), and 0.68 (p < 0.001), respectively. Receiver-operating curve (ROC) analysis revealed VASDA to be more specific than either HAQ (0.95 vs 0.85; p < 0.001) or VASQOL (0.95 vs 0.93; p < 0.001) for the detection of response to treatment in active PMR. Overall, fibrinogen showed superior correlation coefficients with the various PRO than either of the standard biomarkers ESR or CRP. In addition, standardized response means for fibrinogen, ESR, and CRP were 1.63, 1.2, and 1.05, respectively, indicating that plasma fibrinogen was the most responsive biomarker for assessment of change in disease activity. CONCLUSION: VASDA and VASQOL are the most responsive PRO to changes in disease activity in PMR. In addition, plasma fibrinogen demonstrated greater responsiveness to changes in disease activity and superior correlation with the various PRO measures recorded than did the standard biomarkers ESR and CRP.