Development of aortic aneurysm/dilatation during the followup of patients with giant cell arteritis: a cross-sectional screening of fifty-four prospectively followed patients

Vascular disease persistence in giant cell arteritis: are stromal cells neglected?

Giant cell arteritis (GCA), the most common systemic vasculitis, is characterised by aberrant interactions between infiltrating and resident cells of the vessel wall. Ageing and breach of tolerance are prerequisites for GCA development, resulting in dendritic and T-cell dysfunction. Inflammatory cytokines polarise T-cells, activate resident macrophages and synergistically enhance vascular inflammation, providing a loop of autoreactivity. These events originate in the adventitia, commonly regarded as the biological epicentre of the vessel wall, with additional recruitment of cells that infiltrate and migrate towards the intima. Thus, GCA-vessels exhibit infiltrates across the vascular layers, with various cytokines and growth factors amplifying the pathogenic process. These events activate ineffective repair mechanisms, where dysfunctional vascular smooth muscle cells and fibroblasts phenotypically shift along their lineage and colonise the intima. While high-dose glucocorticoids broadly suppress these inflammatory events, they cause well known deleterious effects. Despite the emerging targeted therapeutics, disease relapse remains common, affecting >50% of patients. This may reflect a discrepancy between systemic and local mediators of inflammation. Indeed, temporal arteries and aortas of GCA-patients can show immune-mediated abnormalities, despite the treatment induced clinical remission. The mechanisms of persistence of vascular disease in GCA remain elusive. Studies in other chronic inflammatory diseases point to the fibroblasts (and their lineage cells including myofibroblasts) as possible orchestrators or even effectors of disease chronicity through interactions with immune cells. Here, we critically review the contribution of immune and stromal cells to GCA pathogenesis and analyse the molecular mechanisms by which these would underpin the persistence of vascular disease.

Relapses in giant cell arteritis: Updated review for clinical practice

Giant cell arteritis (GCA), the most common primary vasculitis in adults, is a granulomatous systemic vasculitis usually affecting the aorta and its major branches, particularly the carotid and vertebral arteries. Although remission can be achieved in most patients with GCA using high-dose glucocorticoids (GC), relapses are frequent, occurring in >40% of GC-only treated patients, mostly during the first two years after diagnosis. Relapsing courses lead to high GC exposure, increasing the risk of treatment-related adverse effects. Although tocilizumab is an efficacious GC-sparing therapy that allows increased sustained remission and reduced cumulative GC doses, relapses are common after drug discontinuation. This narrative review examines the most relevant features of relapses in GCA, including its definition, classification, frequency, clinical, laboratory, and imaging characteristics, chronology, probable pathophysiology, and predictive factors. In addition, we discuss treatment options for relapsing patients and the effect of relapses on patient outcomes.

Multimodality imaging to assess diagnosis and evaluate complications of large vesselarteritis

Different types of vasculitis can be distinguished according to the blood vessel's size that is preferentially affected: large-vessel, medium-vessel, and small-vessel vasculitides. Giant cell arteritis (GCA) and Takayasu's arteritis (TAK) are the main forms of large-vessel vasculitis, and may lead to lumen narrowing. Clinical manifestations of arterial narrowing on the short- and long term include vision loss, stroke, limb ischemia, and heart failure. Imaging tools are well established diagnostic tests for large-vessel vasculitis and may aid therapy monitoring in selected cases while providing important information regarding the occurrence of vascular damage, tissue and organ complications. This review aims to provide the current status of multimodality imaging for the diagnosis and identification of vascular complications in the field of large vessel vasculitis.

Polymyalgia rheumatica is a risk factor for more recalcitrant disease in giant cell arteritis: A retrospective cohort study

OBJECTIVES

To evaluate differences in presentation and outcome of giant cell arteritis (GCA) patients with and without polymyalgia rheumatica (PMR) symptoms.

METHODS

Consecutive patients diagnosed with GCA between 2000 and 2020 and followed for ≥12 months at the University Hospitals Leuven (Belgium), were included retrospectively.

RESULTS

We included 398 GCA patients, of which 181 (45%) with PMR symptoms. Patients with PMR symptoms had a longer symptom duration (11 vs 6 weeks, p < 0.001). They less frequently reported fever (19% vs 28%, p = 0.030) and fatigue (52% vs 64%, p = 0.015) and tended to have less permanent vision loss (12% vs 19%, p = 0.052). There was no difference in the cumulative oral GC dose at 2 years (4.4 vs 4.3 g methylprednisolone, p = 0.571). However, those with PMR symptoms were treated with higher GC doses during subsequent follow-up (p < 0.05 from 38 months after diagnosis) and had a lower probability of stopping GC (62% vs 71%, HR 0.74 [95%CI 0.58-0.94], p = 0.018) with a longer median duration of GC treatment (29 vs 23 months, p = 0.021). In addition, presence of PMR symptoms was associated with an increased risk of relapse (64% vs 51%, HR 1.38 [95%CI 1.06-1.79], p = 0.017) with a higher number of relapses (1.47 [95%CI 1.30-1.65] vs 1.16 relapses [95%CI 1.02-1.31], p = 0.007). Patients with PMR symptoms less frequently developed thoracic aortic aneurysms during follow-up (3% vs 11%, p = 0.005).

CONCLUSION

GCA patients with PMR symptoms had more recalcitrant disease with a higher risk of relapse and longer duration of GC treatment with need for higher GC doses.

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.

Evolution and outcomes of aortic dilations in giant cell arteritis

OBJECTIVES

To identify factors associated with the progression of giant cell arteritis (GCA)-related or associated aortic dilations.

METHODS

In this retrospective study, 47 GCA patients with aortic dilation were longitudinally analyzed. Each patient underwent ≥2 imaging scans of the aorta during the follow-up. Three progression statuses of aortic dilations were distinguished: fast-progressive (FP) defined by a progression of the aortic diameter ≥5 mm/year or ≥1 cm/2 years, slow progressive (SP) by a progression of the aortic diameter >1 mm during the follow-up, and not progressive (NP) when aortic diameter remained stable.

RESULTS

Among the 47 patients with aortic dilation, the thoracic section was involved in 87 % of patients. Within a total follow-up of 89 [6-272] months, we identified 13 (28 %) patients with FP dilations, and 16 (34 %) and 18 (38 %) patients with SP and NP dilations, respectively. No differences regarding baseline characteristics, cardiovascular risk factors or treatments were observed among the 3 groups. However, FP patients more frequently showed atheromatous disease (p = 0.04), with a more frequent use of statins (p = 0.04) and antiplatelet agents (p = 0.02). Among the 27 (57 %) patients with aortitis, aortic dilation developed on an inflammatory segment in 23 (85 %). Among the FP patients who underwent aortic surgery with available histology (n = 3), all presented active vasculitis.

CONCLUSION

This study suggests that aortic inflammation, as well as atheromatous disease, might participate in the fast progression of aortic dilation in GCA.

Effectiveness and safety of a 26-week taper regimen of glucocorticoid in GCA patients: Results from a prospective cohort study

OBJECTIVES

To assess the effectiveness and safety of the 26-week tapering regimen of glucocorticoids (GC) used in the GiACTA trial in a prospective cohort of treatment-naive, biopsy-proven GCA patients.

METHODS

Patients with a new diagnosis of biopsy-proven GCA enrolled in the GC arm of the START project (molecular stratification of patients with GCA to tailor GC and tocilizumab therapy) were included. All patients were treated with the 26-week taper regimen of GC used in the GiACTA trial. The primary endpoint was the rate of relapse-free remission at week 52. The secondary endpoints were the proportion of patients with incident aortic damage, cumulative GC doses and GC-related adverse events (AE).

RESULTS

22 patients were included between December 2018 and February 2022. At week 52, 10 patients (45 %, 95 % CI 24-68) were in relapse-free remission. After a median (IQR) follow-up of 35 (22-40) months, 7 patients (32 %, 95 % CI 14-55) were in relapse-free remission. 18 patients with baseline large-vessel imaging underwent CT angiography at the end of the follow-up. No patients had evidence of new aortic dilation, significant progression of aortic damage or large vessel stenosis. 15/22 patients (68 %) had at least one relapse during follow-up. No patients developed visual or cerebrovascular manifestations during relapses. 15/22 (68 %) patients had at least one GC-related AE.

CONCLUSIONS

A 26 week taper regimen of GC was effective and safe in inducing and maintaining remission in a sizeable proportion of newly diagnosed GCA patients. However, the frequency of GC-related adverse events was high.

Treatment of giant cell arteritis with ultra-short glucocorticoids and tocilizumab: the role of imaging in a prospective observational study

OBJECTIVES

To assess the impact of tocilizumab (TCZ) monotherapy after ultra-short-pulse glucocorticoids (GCs) on clinical manifestations, and vessel inflammation and damage in large vessel-GCA (LV-GCA).

METHODS

In this prospective observational study, we enrolled patients with active LV-GCA. All patients received 500 mg per day i.v. methylprednisolone for three consecutive days and weekly s.c. TCZ injections from day 4 until week 52. PET/CT was performed on all patients at baseline and at weeks 24 and 52. The primary end points were the reduction in the PET vascular activity score (PETVAS) at weeks 24 and 52 compared with baseline, and the proportion of patients with relapse-free remission at weeks 24 and 52. The secondary end point was the proportion of patients with new aortic dilation at weeks 24 and 52.

RESULTS

A total of 18 patients were included (72% female, mean age 68.5 years). Compared with the baseline value, a significant reduction in the PETVAS was observed at weeks 24 and 52, mean (95% CI) reductions -8.6 (-11.5 to -5.7) and -10.4 (-13.6 to -7.2), P = 0.001 and 0.002, respectively. The proportion of patients with relapse-free remission at weeks 24 and 52 was 10/18 (56%, 95% CI 31-78) and 8/17 (47%, 95% CI 23-72), respectively. At weeks 24 and 52, no patient had shown new aortic dilation. However, 4 patients who had shown aortic dilation at baseline showed a significant increase in aortic diameter (≥5 mm) at week 52.

CONCLUSION

TCZ monotherapy after ultra-short-pulse GCs controlled the clinical symptoms of GCA and reduced vascular inflammation.

TRIAL REGISTRATION

ClinicalTrials.gov, https://clinicaltrials.gov, NCT05394909.

Prevalence and characteristics of subclinical giant cell arteritis in polymyalgia rheumatica

OBJECTIVE

The main objective of this study was to analyse the prevalence and characteristics of subclinical GCA in patients with PMR.

METHODS

This was a cross-sectional multicentre international study of consecutive patients with newly diagnosed PMR without symptoms or signs suggestive of GCA. All patients underwent US of the temporal superficial, common carotid, subclavian and axillary arteries. Patients with halo signs in at least one examined artery were considered to have subclinical GCA. The clinical, demographic and laboratory characteristics of the PMR group without subclinical vasculitis were compared with subclinical GCA, and the pattern of vessel involvement was compared with that of a classical single-centre GCA cohort.

RESULTS

We included 346 PMR patients, 267 (77.2%) without subclinical GCA and 79 (22.8%) with subclinical GCA. The PMR patients with subclinical GCA were significantly older, had a longer duration of morning stiffness and more frequently reported hip pain than PMR without subclinical GCA. PMR with subclinical GCA showed a predominant extracranial large vessel pattern of vasculitic involvement compared with classical GCA, where the cranial phenotype predominated. The patients with PMR in the classical GCA group showed a pattern of vessel involvement similar to classical GCA without PMR but different from PMR with subclinical involvement.

CONCLUSION

More than a fifth of the pure PMR patients had US findings consistent with subclinical GCA. This specific subset of patients showed a predilection for extracranial artery involvement. The optimal screening strategy to assess the presence of vasculitis in PMR remains to be determined.

Association between the patterns of large-vessel lesions and treatment outcomes in patients with large-vessel giant cell arteritis

OBJECTIVES

We aimed to identify associations between patterns of large-vessel lesions of large-vessel giant cell arteritis (LV-GCA) and treatment outcomes.

METHODS

We extracted data on 68 newly diagnosed patients with LV-GCA from a retrospective, multi-centric, nationwide registry of GCA patients treated with glucocorticoids between 2007 and 2014. Patients with aortic lesions were identified based on the findings from contrast-enhanced computed tomography, magnetic resonance imaging, or positron emission tomography-computed tomography (Group 2, n = 49). Patients without aortic lesions were subdivided into LV-GCA with or without subclavian lesions defined as Group 1 (n = 9) or Group 3 (n = 10), respectively. The primary outcome evaluation was failure to achieve clinical remission by Week 24 and/or relapse within 104 weeks.

RESULTS

The mean age and proportion of patients with cranial lesions and polymyalgia rheumatica in Group 2 were numerically lower than in the other two groups. Large-vessel lesions in Group 3 included carotid, pulmonary, renal, hepatic, or mesenteric lesions. The cumulative rate of poor treatment outcomes >2 years was 11.1%, 55.3%, and 88.0% in Groups 1, 2, and 3, respectively (by Kaplan-Meier analysis). The mean time to poor outcome was significantly different between the groups.

CONCLUSIONS

Classification by subclavian and aortic lesions may be useful to determine treatment strategy.

Association Between Vascular 18F-Fluorodeoxyglucose Uptake at Diagnosis and Change in Aortic Dimensions in Giant Cell Arteritis : A Cohort Study

BACKGROUND

Previous studies have shown that patients with giant cell arteritis (GCA) who have vascular 18F-fluorodeoxyglucose (FDG) uptake at diagnosis are at increased risk for thoracic aortic complications.

OBJECTIVE

To measure the association between vascular FDG uptake at diagnosis and the change in aortic dimensions.

DESIGN

Prospective cohort study.

SETTING

University Hospitals Leuven.

PATIENTS

106 patients with GCA and FDG positron emission tomography (PET) imaging 3 days or less after initiation of glucocorticoids.

MEASUREMENTS

Patients had PET and computed tomography (CT) imaging at diagnosis and CT imaging yearly for a maximum of 10 years. The PET scans were scored 0 to 3 in 7 vascular areas and summed to a total vascular score (TVS). The PET scan results were positive when FDG uptake was grade 2 or greater in any large vessel. The association between vascular FDG uptake and aortic dimensions was estimated by linear mixed-effects models with random intercept and slope.

RESULTS

When compared with patients with a negative PET scan result, those with a positive scan result had a greater increase in the diameter of the ascending aorta (difference in 5-year progression, 1.58 mm [95% CI, 0.41 to 2.74 mm]), the diameter of the descending aorta (1.32 mm [CI, 0.38 to 2.26 mm]), and the volume of the thoracic aorta (20.5 cm³ [CI, 4.5 to 36.5 cm³]). These thoracic aortic dimensions were also positively associated with TVS. Patients with a positive PET scan result had a higher risk for thoracic aortic aneurysms (adjusted hazard ratio, 10.21 [CI, 1.25 to 83.3]).

LIMITATION

The lengthy inclusion and follow-up period resulted in missing data and the use of different PET machines.

CONCLUSION

Higher TVS was associated with greater yearly increase in thoracic aortic dimensions. Performing PET imaging at diagnosis may help to estimate the risk for aortic aneurysm formation.

PRIMARY FUNDING SOURCE

None.

Duration of Treatment With Glucocorticoids in Giant Cell Arteritis: A Systematic Review and Meta-analysis

ABSTRACT

The aim of this meta-analysis was to estimate the mean duration of glucocorticoid (GC) treatment in patients with giant cell arteritis. PubMed, EMBASE, and Cochrane databases were searched from inception until November 30, 2021. The outcome measures were the proportion of patients on GCs at years 1, 2, and 5 after diagnosis and the mean GC dose (in the entire cohort and expressed in prednisone equivalents) at these time points. Twenty-two studies involving a total of 1786 patients were included. The pooled proportions of patients taking GCs at years 1, 2, and 5 were 89.7% (95% confidence interval [CI], 83.2%-93.9%), 75.2% (95% CI, 58.7%-86.6%), and 44.3% (95% CI, 15.2%-77.6%), respectively. The pooled GC dose at years 1 and 2 was 9.1 mg/d (95% CI, 2.8-15.5 mg/d) and 7.8 mg/d (95% CI, 1.4-14.1 mg/d), respectively. The proportion of patients taking GCs at year 1 was lower in multicenter studies ( p = 0.003), in randomized controlled trials ( p = 0.01), and in studies using a GC-tapering schedule ( p = 0.01). There were no significant differences in the proportion of patients taking GCs at years 1 and 2 according to study design (retrospective vs. prospective), initial GC dose, use of pulse GCs, publication year, enrolment period, duration of follow-up, age, and sex. This meta-analysis showed that giant cell arteritis is a chronic disease that requires substantial and prolonged GC treatment in a considerable proportion of patients. A predefined GC-tapering schedule may help to avoid inadequately long GC treatment.

Persistent aortic inflammation in patients with giant cell arteritis

OBJECTIVES

To investigate the clinicopathologic features of patients with giant cell arteritis (GCA) who had thoracic aorta aneurysm or dissection surgery.

METHODS

Patients who had thoracic aorta surgery between January 1, 2000, and December 31, 2021, at the Mayo Clinic, Rochester, Minnesota, were identified with current procedural terminology (CPT) codes. The identified patients were screened for a prior diagnosis of GCA with diagnostic codes and electronic text search. The available medical records of all the patients of interest were manually reviewed. Thoracic aorta tissues obtained during surgery were re-evaluated in detail by pathologists. The clinicopathologic features of these patients were analyzed. Overall observed survival was compared with lifetable rates from the United States population.

RESULTS

Of the 4621 patients with a CPT code for thoracic aorta surgery, 49 had a previous diagnosis of GCA. Histopathologic evaluation of the aortic tissue revealed active aortitis in most patients with GCA (40/49, 82%) after a median (IQR) of 6.0 (2.6-10.3) years from GCA diagnosis. All patients were considered in clinical remission at the time of aortic surgery. The overall mortality compared to age and sex-matched general population was significantly increased with a standardized mortality ratio of 1.55 (95% CI, 1.05-2.19).

CONCLUSION

Histopathologic evaluation of the thoracic aorta obtained during surgery revealed active aortitis in most patients with GCA despite being considered in clinical remission several years after GCA diagnosis. Chronic, smoldering aortic inflammation likely contributes to the development of aortic aneurysm and dissection in GCA.

The role of autoimmunity and autoinflammation in giant cell arteritis: A systematic literature review

Giant cell arteritis is the most common form of large vessel vasculitis and preferentially involves large and medium-sized arteries in patients over the age of 50. Aggressive wall inflammation, neoangiogenesis and consecutive remodeling processes are the hallmark of the disease. Though etiology is unknown, cellular and humoral immunopathological processes are well understood. Matrix metalloproteinase-9 mediated tissue infiltration occurs through lysis of basal membranes in adventitial vessels. CD4+ cells attain residency in immunoprotected niches, differentiate into vasculitogenic effector cells and enforce further leukotaxis. Signaling pathways involve the NOTCH1-Jagged1 pathway opening vessel infiltration, CD28 mediated T-cell overstimulation, lost PD-1/PD-L1 co-inhibition and JAK/STAT signaling in interferon dependent responses. From a humoral perspective, IL-6 represents a classical cytokine and potential Th-cell differentiator whereas interferon-γ (IFN- γ) has been shown to induce chemokine ligands. Current therapies involve glucocorticoids, tocilizumab and methotrexate application. However, new agents, most notably JAK/STAT inhibitors, PD-1 agonists and MMP-9 blocking substances, are being evaluated in ongoing clinical trials.

18-Fluorodeoxyglucose positron emission tomography/computed tomography for large vessel vasculitis in clinical practice

Diagnosis, prognostic assessment, and monitoring disease activity in patients with large vessel vasculitis (LVV) can be challenging. Early recognition of LVV and treatment adaptation is essential because vascular complications (aneurysm, dilatations, ischemic complications) or treatment related side effects can occur frequently in these patients. 18-fluorodeoxyglucose positron emission tomography/computed tomography (2-[18F]FDG-PET/CT) is increasingly used to diagnose, follow, and evaluate treatment response in LVV. In this review, we aimed to summarize the current evidence on the value of 2-[18F]FDG-PET/CT for diagnosis, follow, and treatment monitoring in LVV.

Epidemiology and predictors of relapse in giant cell arteritis: A systematic review and meta-analysis

OBJECTIVES

The aim of this study was to estimate the timing of relapse, the prevalence of multiple relapses and the predictors of relapse in patients with giant cell arteritis (GCA).

METHODS

PubMed, Embase and Cochrane databases were searched from inception till November, 30 2021. Outcome measures include cumulative relapse rate (CRR) of first relapse at year 1, 2, and 5 after treatment initiation, CRR of second and third relapse and predictors of relapse.

RESULTS

Thirty studies (2595 patients) were included for timing of relapse, 16 studies (1947 patients) for prevalence of multiple relapses and 40 studies (4213 patients) for predictors of relapse. One-year, 2-year and 5-year CRRs were 32% [95% confidence interval (CI) 22-43%], 44% [95% CI 31-59%], and 47% [95% CI 27-67%], respectively. The duration of scheduled glucocorticoid therapy was negatively associated with the 1-year CRR (P=0.03). CRR of second and third relapse were 30% [95% CI 21-40] and 17% [95% CI 8-33%], respectively. Female sex (OR 1.43) and large vessel involvement (OR 2.04) were predictors of relapse.

CONCLUSION

Relapse occurred in almost half of GCA patients mainly during the first two years after diagnosis. One in three patients had multiple relapses. The optimal glucocorticoid tapering schedule, which seeks a balance between the lowest relapse risk and the shortest glucocorticoid duration, needs to be determined in future studies. Longer scheduled glucocorticoid therapy or early introduction of glucocorticoid-sparing agents may be warranted in female patients and patients with large vessel involvement.

Association of immunological parameters with aortic dilatation in giant cell arteritis: a cross-sectional study

Aortic dilatation (AD) occurs in up to 30% of patients with giant cell arteritis (GCA). Reliable biomarkers for AD development, however, are still absent. The aim of this exploratory study was to evaluate whether immunological parameters are associated with the occurrence of AD in GCA. Cross-sectional study on 20 GCA patients with AD, 20 GCA patients without AD, and 20 non-GCA controls without AD measuring leukocytes, neutrophils, lymphocytes, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), serum amyloid A (SAA), interferon (IFN)-α, IFN-γ, IFN-γ-induced protein 10 (IP-10), interleukin (IL) 5, IL-8, IL-10, IL-17A, IL-18, IL-1 receptor antagonist, tumor necrosis factor (TNF)-α, platelet-derived growth factor (PDGF), L-selectin, P-selectin, and soluble intercellular adhesion molecule 1 (sICAM-1). AD was measured by aortic contrast-enhanced computed tomography and defined by enlargement of the aorta above population-based aortic diameters adjusted by age, gender, and body surface area. No significant differences were observed between GCA patients with AD and GCA patients without AD concerning levels of leukocytes, neutrophils, lymphocytes, CRP, ESR, SAA, IL-8, IL-18, PDGF, IP-10, selectins, and sICAM-1. Values of IFN-α, IFN-γ, IL-5, IL-10, IL-17A, IL-1 receptor antagonist, and TNF-α were all below the detection limits in more than 70% of subjects. Lymphocytes and CRP revealed positive correlations with the diameter of the thoracic descending aorta. Immunological parameters were not useful to conclude on the presence of AD in GCA. Further studies are required to test if CRP and lymphocytes may be useful to predict future development of AD in GCA.

Giant cell arteritis: Update on clinical manifestations, diagnosis, and management

Giant cell arteritis (GCA) is the most common vasculitis affecting people older than 50 years. The last decades have shed new light on the clinical paradigm of this condition, expanding its spectrum beyond cranial vessel inflammation. GCA can be now considered a multifaceted vasculitic syndrome encompassing inflammation of cranial and extra-cranial arteries and girdles, isolated or combined. Such heterogeneity often leads to diagnostic delays and increases the likelihood of acute and chronic GCA-related damage. On the other hand, the approach to suspected GCA patients has been revolutionized by the introduction of vascular ultrasound which allows a rapid, cost-effective, and non-invasive GCA diagnosis. Likewise, the use of tocilizumab is now part of the therapeutic algorithm of GCA and ensures a satisfactory disease control even in steroid-refractory patients. Nonetheless, some aspects of GCA still need to be clarified, including the clinical correlation of different histological patterns, and the prevention of long-term vascular complications. This narrative review depicts the diagnostic and therapeutic aspects of GCA most relevant in clinical practice, with a focus on clinical updates and novelties introduced over the last decade.

Vascular/perivascular inflammation in IgG4-related disease

BACKGROUND

Immunoglobulin G4-related disease (IgG4-RD) is characterized by the infiltration of IgG4-positive plasma cells and fibrosclerotic inflammation in multiple organs. Although vascular complications are present in some patients with IgG4-RD, vascular and/or perivascular inflammatory activity compared to control subjects remains unknown. This study sought to investigate vascular/perivascular inflammation in IgG4-RD patients compared to control subjects using 18F-fluorodeoxyglucose-positron emission tomography combined with computed tomography (FDG-PET/CT).

METHODS

We examined 37 consecutive patients diagnosed as IgG4-RD (29 males, mean age of 64.3 ± 8.3 years old), who underwent FDG-PET/CT. Thirty-seven age- and gender-matched subjects without IgG4-RD were employed as controls. Vascular/perivascular inflammation was quantified by blood-normalized standardized uptake value, known as a target-to-background ratio (TBR).

RESULTS

All IgG4-RD patients presented with multiple region involvements. Twelve (32.4%) of the IgG4-RD patients had vascular complications, all of which appeared in the abdominal aorta. IgG4-RD patients had significantly higher TBR values in the descending aorta, abdominal aorta, and common iliac artery than control subjects. Also, IgG4-RD patients with vascular complication exhibited higher TBR values in the infra-renal aorta and common iliac artery than those without vascular complication.

CONCLUSIONS

We found that vascular FDG activity is significantly elevated in IgG4-RD patients regardless of vascular complication than control subjects. FDG-PET/CT is a useful modality for assessing vascular/perivascular inflammation, which may contribute vascular complication in IgG4-RD patients.

Unexplained chest pain in a patient with giant cell arteritis? Think aortic dissection

Giant cell arteritis (GCA) is the commonest of the large-vessel vasculitides. Aortic inflammation in patients with GCA was first described over 80 years ago, but it has only been possible to study this systematically following the development of more sophisticated imaging techniques such as computed tomography angiography, magnetic resonance angiography and positron emission tomography. Both NICE and the European League Against Rheumatism (EULAR) recognise that aortic dissection may complicate GCA but stop short of recommending routine imaging. We report a case that highlights a possible need for large-vessel imaging at the time of diagnosis and during follow-up to enable earlier recognition of aortitis and associated complications including dissection.

Blocking GM-CSF receptor α with mavrilimumab reduces infiltrating cells, pro-inflammatory markers and neoangiogenesis in ex vivo cultured arteries from patients with giant cell arteritis

BACKGROUND

Effective and safe therapies are needed for the treatment of patients with giant cell arteritis (GCA). Emerging as a key cytokine in inflammation, granulocyte-macrophage colony stimulating factor (GM-CSF) may play a role in promoting inflammation in GCA.

OBJECTIVES

To investigate expression of GM-CSF and its receptor in arterial lesions from patients with GCA. To analyse activation of GM-CSF receptor-associated signalling pathways and expression of target genes. To evaluate the effects of blocking GM-CSF receptor α with mavrilimumab in ex vivo cultured arteries from patients with GCA.

METHODS

Quantitative real time PCR, in situ RNA hybridisation, immunohistochemistry, immunofluorescence and confocal microscopy, immunoassay, western blot and ex vivo temporal artery culture.

RESULTS

GM-CSF and GM-CSF receptor α mRNA and protein were increased in GCA lesions; enhanced JAK2/STAT5A expression/phosphorylation as well as increased expression of target genes CD83 and Spi1/PU.1 were observed. Treatment of ex vivo cultured GCA arteries with mavrilimumab resulted in decreased transcripts of CD3ε, CD20, CD14 and CD16 cell markers, and reduction of infiltrating CD16 and CD3ε cells was observed by immunofluorescence. Mavrilimumab reduced expression of molecules relevant to T cell activation (human leukocyte antigen-DR [HLA-DR]) and Th1 differentiation (interferon-γ), the pro-inflammatory cytokines: interleukin 6 (IL-6), tumour necrosis factor α (TNFα) and IL-1β, as well as molecules related to vascular injury (matrix metalloprotease 9, lipid peroxidation products and inducible nitric oxide synthase [iNOS]). Mavrilimumab reduced CD34 + cells and neoangiogenesis in GCA lesions.

CONCLUSION

The inhibitory effects of mavrilimumab on multiple steps in the GCA pathogenesis cascade in vitro are consistent with the clinical observation of reduced GCA flares in a phase 2 trial and support its development as a therapeutic option for patients with GCA.

Increased risk of thoracic aortic complications among patients with giant cell arteritis: a nationwide, population-based cohort study

OBJECTIVE

To assess the risk of aortic aneurysms (AA), aortic dissections (AD) and peripheral arterial disease (PAD) among patients with GCA.

METHODS

In this nationwide, population-based cohort study using Danish national health registries, we identified all incident GCA patients ≥50 years between 1996 and 2018 who redeemed three or more prescriptions for prednisolone. Index date was the date of redeeming the third prednisolone prescription. Case definition robustness was checked through sensitivity analysis. We included general population referents matched 1:10 by age, sex and calendar time. Using a pseudo-observation approach, we calculated 5-, 10- and 15-year cumulative incidence proportions (CIP) and relative risks (RR) of AA, AD and PAD with death as a competing risk.

RESULTS

We included 9908 GCA patients and 98 204 referents. The 15-year CIP of thoracic AA, abdominal AA, AD and PAD in the GCA cohort were 1.9% (95% CI 1.5, 2.2), 1.8% (1.4-2.2), 1.0% (0.7-1.2) and 4.8% (4.2-5.3). Compared with the referents, the 15-year RR were 11.2 (7.41-16.9) for thoracic AA, 6.86 (4.13-11.4) for AD, 1.04 (0.83-1.32) for abdominal AA and 1.53 (1.35-1.74) for PAD. Among GCA patients, female sex, age below 70 years and positive temporal artery findings were risk factors for developing thoracic AA. The median time to thoracic AA was 7.5 years (interquartile range 4.4-11.2) with a number needed to be screened of 250 (167-333), 91 (71-111) and 53 (45-67) after 5, 10 and 15 years.

CONCLUSION

Patients with GCA have a markedly increased risk of developing thoracic AA and AD, but no increased risk of abdominal AA.

Clinically isolated aortitis: imaging features and clinical outcomes: comparison with giant cell arteritis and giant cell aortitis

(1) describe imaging features of CIA, (2) compare dilation rate and wall thickening of aortic aneurysms in patients with CIA versus those with giant cell arteritis/aortitis (GCA), (3) present clinical outcomes of CIA patients. Retrospective search of electronic records from 2004 to 2018 yielded 71 patients, 52 of whom were female, with a mean age of 67.5 ± 9.0 years old, with a new clinical diagnosis of cranial or extracranial GCA (GCA group), and giant cell aortitis revealed by the aortic biopsy (CIA group). Comparisons between groups were conducted using the Wilcoxon rank-sum and Fisher's exact tests. Survival from the date of initial diagnosis to the end of data collection was compared between the two groups through a log-rank test. CIA patients (n = 23; 32%) presented with cardiovascular symptoms, and none had systemic inflammatory symptoms. Inflammatory markers were significantly higher among GCA patients than among CIA patients (p < 0.0001). The CIA group demonstrated thoracic aortic aneurysms without wall thickening. None of the GCA patients (n = 48; 68%) had aneurysmal dilation in the aorta at the time of diagnosis. None of the four CIA patients had FDG uptake in the aorta, while nine out of 13 GCA patients had FDG uptake in the vessels. There was no statistically significant difference in the survival between the two groups (p = 0.12). CIA patients presented with cardiovascular symptoms and was characterized by aneurysm of the aorta without the involvement of the infrarenal aortic segment. The role of FDG-PET/CT in CIA is less certain, though none of the patients in this cohort had FDG uptake in the vessels.

Incidence and predictors of thoracic aortic damage in biopsy-proven giant cell arteritis

Objective: To describe the frequency and predisposing factors of aortic structural disease among patients with biopsy-proven giant cell arteritis (GCA).Method: A retrospective review identified all patients with biopsy-proven GCA from 1998 to 2013 with aortic imaging. Kaplan-Meier methods were used to estimate cumulative incidence and Cox models were used to examine potential predictors of development of aneurysm/dilatation of the thoracic aorta.Results: The cohort included 114 patients with aortic imaging performed within a median time of 1.8 months from GCA diagnosis. Fifty-seven patients (50%) had at least one additional follow-up imaging study. At the first imaging study, 8% had evidence of aneurysm/dilatation and 25% thickening of the thoracic aorta. Excluding prevalent cases, the cumulative incidence for aneurysm/dilatation of the thoracic aorta during follow-up was 0% at both 1 year and 2 years but increased to 10% at 5 years. The sole predictor for development of thoracic aortic aneurysm/dilatation was current smoking (hazard ratio 28.8, 95% confidence interval 1.62, 511.4; p = 0.02).Conclusion: Thoracic aortic aneurysm/dilatation was seen in 8% of patients at baseline. Among patients without aortic disease, the cumulative incidence of aortic disease was 10% at 5 years after diagnosis. Current smokers were at an increased risk for developing thoracic aortic damage. Surveillance for aortic damage should be pursued in patients with GCA, particularly those with a smoking history.

[The current place of non-invasive large-vessel imaging in the diagnosis and follow-up of giant cell arteritis]

Large vessel involvement in giant cell arteritis has long been described, although its right frequency and potential prognostic value have only been highlighted for two decades. Large vessel involvement not only is associated with a high incidence of late aortic aneurysms, but also might cause greater resistance to glucocorticoids and longer treatment duration, as well as worse late cardiovascular outcomes. These data were brought to our attention, thanks to substantial progress recently made in large vessel imaging. This relies on four single, often complementary, approaches of varying availability: colour Doppler ultrasound, contrast-enhanced computed tomography with angiography and, magnetic resonance imaging, which all demonstrate homogeneous circumferential wall thickening and describe structural changes; 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET/CT), which depicts wall inflammation and assesses many vascular territories in the same examination. In addition, integrated head-and-neck PET/CT can accurately and reliably diagnose cranial arteritis. All four procedures exhibit high diagnostic performance for a large vessel arteritis diagnosis so that the choice is left to the physician, depending on local practices and accessibility; the most important is to carry out the chosen modality without delay to avoid false or equivocal results, due to early vascular oedema changes as a result of high dose glucocorticoid treatment. Yet, ultrasound study of the superficial cranial and subclavian/axillary arteries remains a first line assessment aimed at strengthening and expediting the clinical diagnosis as well as raising suspicion of large-vessel involvement. In treated patients, vascular imaging results are poorly correlated with clinical-biological controlled disease so that it is strongly recommended not to renew imaging studies unless a large vessel relapse or complication is suspected. On the other hand, a structural monitoring of aorta following giant cell arteritis is mandatory, but uncertainties remain regarding the best procedural approach, timing of first control and spacing between controls. Individuals at greater risk of developing aortic complication, e.g. those with classic risk factors for aneurysm and/or visualised aortitis, should be monitored more closely.

Diagnosis of giant cell arteritis

GCA is the most common form of primary systemic vasculitis affecting older people. It is considered a clinical emergency because it can lead to irreversible blindness in around 20% of untreated cases. High doses of glucocorticoids should be initiated promptly to prevent disease-related complications; however, glucocorticoids therapy usually results in significant toxicity. Therefore, correct diagnosis is crucial. For many years, temporal artery biopsy has been considered the diagnostic ‘gold standard’ for GCA, but it has many limitations (including low sensitivity). US has proven to be effective for diagnosing GCA and can reliably replace temporal artery biopsy in particular clinical settings. In cases of suspected GCA with large-vessel involvement, other imaging modalities can be used for diagnosis (e.g. CT and PET). Here we review the current evidence for each diagnostic modality and propose an algorithm to diagnose cranial-GCA in a setting with rapid access to high quality US.

Associated factors of poor treatment outcomes in patients with giant cell arteritis: clinical implication of large vessel lesions

Background

Relapses frequently occur in giant cell arteritis (GCA), and long-term glucocorticoid therapy is required. The identification of associated factors with poor treatment outcomes is important to decide the treatment algorithm of GCA.

Methods

We enrolled 139 newly diagnosed GCA patients treated with glucocorticoids between 2007 and 2014 in a retrospective, multi-center registry. Patients were diagnosed with temporal artery biopsy, 1990 American College of Rheumatology classification criteria, or large vessel lesions (LVLs) detected by imaging based on the modified classification criteria. Poor treatment outcomes (non-achievement of clinical remission by week 24 or relapse during 52 weeks) were evaluated. Clinical remission was defined as the absence of clinical signs and symptoms in cranial and large vessel areas, polymyalgia rheumatica (PMR), and elevation of C-reactive protein (CRP) levels. A patient was determined to have a relapse if he/she had either one of the signs and symptoms that newly appeared or worsened after achieving clinical remission. Re-elevation of CRP without clinical manifestations was considered as a relapse if other causes such as infection were excluded and the treatment was intensified. Associated factors with poor treatment outcomes were analyzed by using the Cox proportional hazard model.

Results

Cranial lesions, PMR, and LVLs were detected in 77.7%, 41.7%, and 52.5% of the enrolled patients, respectively. Treatment outcomes were evaluated in 119 newly diagnosed patients who were observed for 24 weeks or longer. The mean initial dose of prednisolone was 0.76 mg/kg/day, and 29.4% received any concomitant immunosuppressive drugs at baseline. Overall, 41 (34.5%) of the 119 patients had poor treatment outcomes; 13 did not achieve clinical remission by week 24, and 28 had a relapse after achieving clinical remission. Cumulative rates of the events of poor treatment outcomes in patients with and without LVLs were 47.5% and 17.7%, respectively. A multivariable model showed the presence of LVLs at baseline was significantly associated with poor treatment outcomes (adjusted hazard ratio [HR] 3.54, 95% CI 1.52–8.24, p = 0.003). Cranial lesions and PMR did not increase the risk of poor treatment outcomes.

Conclusion

The initial treatment intensity in the treatment algorithm of GCA could be determined based upon the presence or absence of LVLs detected by imaging at baseline.

Diagnostic Assessment Strategies and Disease Subsets in Giant Cell Arteritis: Data From an International Observational Cohort

OBJECTIVE

Diagnostic assessment in giant cell arteritis (GCA) is rapidly changing as vascular imaging becomes more available. This study was undertaken to determine if clinical GCA subsets have distinct profiles or reflect differential diagnostic assessments.

METHODS

Patients were recruited from an international cohort and divided into 4 subsets based on a temporal artery (TA) abnormality (positive TA biopsy [TAB] or halo sign on TA ultrasound [TA-US]) and/or evidence of large vessel (LV) involvement on imaging: 1) both TA abnormality and LV involvement (TA+/LV+ GCA); 2) TA abnormality without LV involvement (TA+/LV- GCA); 3) LV involvement without TA abnormality (TA-/LV+ GCA); and 4) clinically diagnosed GCA without LV involvement or TA abnormality (TA-/LV- GCA).

RESULTS

Nine hundred forty-one patients with GCA were recruited from 72 international study sites. Most patients received multiple forms of diagnostic assessment, including TAB (n = 705 [75%]), TA-US (n = 328 [35%]), and LV imaging (n = 534 [57%]). Assessment using TAB, TA-US, and LV imaging confirmed the diagnosis of GCA in 66%, 79%, and 40% of cases, respectively. GCA subsets had distinct profiles independent of diagnostic assessment strategies. TA+/LV- were the most common subset (51%), with a high burden of cranial ischemia. Those in the TA-/LV- subset (26%) had a high prevalence of cranial ischemia and musculoskeletal symptoms. Patients in the TA-/LV+ subset (12%) had prevalent upper extremity vascular abnormalities and a low prevalence of vision loss, and those in the TA+/LV+ subset (11%) were older and had a high prevalence of cranial ischemia, constitutional symptoms, and elevated acute-phase reactant levels.

CONCLUSION

Vascular imaging is increasingly incorporated into the diagnostic assessment of GCA and identifies clinical subsets of patients based on involvement of temporal and extracranial arteries.

Giant cell arteritis-related aortitis with positive or negative temporal artery biopsy: a French multicentre study

Objective: To compare the clinical presentation and outcome of giant cell arteritis (GCA)-related aortitis according to the results of temporal artery biopsy (TAB).Method: Patients with GCA-related aortitis diagnosed between 2000 and 2017, who underwent TAB, were retrospectively included from a French multicentre database. They all met at least three American College of Rheumatology criteria for the diagnosis of GCA. Aortitis was defined by aortic wall thickening > 2 mm on computed tomography scan and/or an aortic aneurysm, associated with an inflammatory syndrome. Patients were divided into two groups [positive and negative TAB (TAB+, TAB-)], which were compared regarding aortic imaging characteristics and aortic events, at aortitis diagnosis and during follow-up.Results: We included 56 patients with TAB+ (70%) and 24 with TAB- (30%). At aortitis diagnosis, patients with TAB- were significantly younger than those with TAB+ (67.7 ± 9 vs 72.3 ± 7 years, p = 0.022). Initial clinical signs of GCA, inflammatory parameters, and glucocorticoid therapy were similar in both groups. Coronary artery disease and/or lower limb peripheral arterial disease was more frequent in TAB- patients (25% vs 5.3%, p = 0.018). Aortic wall thickness and type of aortic involvement were not significantly different between groups. Diffuse arterial involvement from the aortic arch was more frequent in TAB- patients (29.1 vs 8.9%, p = 0.03). There were no differences between the groups regarding overall, aneurism-free, relapse-free, and aortic event-free survival.Conclusion: Among patients with GCA-related aortitis, those with TAB- are characterized by younger age and increased frequency of diffuse arterial involvement from the aortic arch compared to those with TAB+, without significant differences in terms of prognosis.

Magnetic resonance angiography versus 18F-fluorodeoxyglucose positron emission tomography in large vessel vasculitis

With advances in our understanding of the pathogenesis of large vessel vasculitides, we recognise the persistence of inflammation in large vessels, sometimes despite therapy to control clinical symptoms. Achieving an early diagnosis and establishing the extent of disease are important steps in improving our management of these diseases. Imaging is playing an increasing role in the assessment of these patients from diagnosis to prognosis. We review the current and potential role of two important and potentially complementary imaging techniques of magnetic resonance angiography and 18F-fluorodeoxyglucose positron emission tomography in the evaluation of patients with giant cell arteritis and Takayasu arteritis.

Sub-classification of non-inflammatory and inflammatory surgical aortic aneurysms and the association of histological characteristics with potential risk factors

The present study aimed to analyze the histological characteristics of surgical thoracic aortic aneurysm (TAA) and abdominal aortic aneurysm (AAA) specimens on the basis of the most recent consensus documents on non-inflammatory and inflammatory lesions. The current study also aimed to establish an association with various risk factors. Aortic wall specimens were collected from 52 patients (38 men and 14 women; age, 19-80 years) undergoing surgery for aortic dilatation at The Cardiovascular Disease Institute (Iasi, Romania). For histological evaluation, the aortic specimens (39 TAAs and 13 AAAs) were stained with hematoxylin-eosin, Van Giessen, alcian blue and Movat pentachrome. The specimens were evaluated and graded according to the severity of histopathological conditions: Fragmentation of elastic fibers, medial mucoid accumulation, smooth muscle cell loss and medial fibrosis. The severity of atherosclerotic lesions in surgically resected segments of the aorta were graded as follows: i) mild=1; ii) moderate=2; and iii) severe=3. The risk factors associated with TAA were the male sex (80%), smoking (56%), hypertension (33%) and bicuspid aortic valve (13%). Advanced age (70 years), male sex (69%) and smoking (54%) were determined to be the risk factors of AAA. The histopathological abnormalities included medial degeneration (MD) (82%), atherosclerosis (ATS) (42%) and aortitis (10%). MD was the leading histopathological diagnosis in TAA and the severity of lesions were graded as follows: Mild (8% of cases), moderate (44% of cases) and severe (31% of cases). Severe atherosclerotic lesions were identified in AAA (100% of cases). In the present study, medial degenerative aortic lesions (1, mild; 2, moderate; and 3, severe) significantly correlated with advanced age (>65 years; r=-0.39; P<0.01) and male sex (r=0.27; P<0.05). Significant correlations were also identified between atherosclerotic aortic lesions (1, mild; 2, moderate; and 3, severe) and advanced age (>65 years) (r=-0.40, P<0.01) or smoking (r=-0.29; P<0.05). Advanced age, male sex and smoking were determined to be the main risk factors for the development of degenerative aortic aneurysms.

Large-vessel vasculitis diagnosed between 50 and 60 years: Case-control study based on 183 cases and 183 controls aged over 60 years

BACKGROUND

Age at onset of large-vessel vasculitis (LVV) is commonly used to distinguish giant cell arteritis (GCA) and Takayasu arteritis (TA). However, LVV between age 50 and 60 years may be difficult to classify.

METHODS

We conducted a retrospective study including LVV aged between 50 and 60 years at onset (LVV_50-60, cases) and compared them to LVV aged over 60 years (LVV_>60, controls). LVV was defined histologically and/or morphologically. Controls fulfilled ACR 1990 criteria for GCA or presented isolated aortitis.

RESULTS

We included 183 LVV_50-60 and 183 gender-matched LVV_>60. LVV_50-60 had more frequent peripheral limb manifestations (23 vs. 5%), and less frequent cephalic (73 vs. 90%) and ocular signs (17 vs. 27%) than LVV_>60. Compared to LVV_>60, CT angiography and PET/CT scan were more frequently abnormal in LVV_50-60 (74 vs. 38%, and 90 vs. 72%, respectively), with aorta being more frequently involved (78 vs. 47%). By multivariate analysis, absence of cephalic symptoms, presence of peripheral limb ischemia and aorta involvement, and increased CRP level were significantly associated with LVV_50-60 presentation compared to LVV_>60. At last follow-up, compared to LVV_>60, LVV_50-60 received significantly more lines of treatment (2 vs. 1), more frequent biologics (12 vs. 3%), had more surgery (10 vs. 0%), and had higher prednisone dose (8.8 vs. 6.5 mg/d) at last follow-up, CONCLUSION: LVV onset between 50 and 60 years identifies a subset of patients with more frequent aorta and peripheral vascular involvement and more refractory disease compared to patients with LVV onset after 60.

PET/CT for Diagnosis and Management of Large-Vessel Vasculitis

PURPOSE OF REVIEW

This review aims to discuss the use of fluorodeoxyglucose (FDG) positron emission tomography (PET/CT) for diagnosis and management of patients with large-vessel vasculitis (LVV).

RECENT FINDINGS

Incidence of LVV is likely underestimated, in part due to its non-specific symptoms. Nevertheless, early diagnosis of LVV is essential to initiate timely therapy in order to prevent vascular complications, such as stenoses and aneurysms. FDG PET/CT imaging has the ability to detect LVV during the acute phase, prior to edema and other vascular structural changes, with its high sensitivity for inflammatory activity. FDG PET/CT was shown to be a powerful prognostic marker by allowing identification of patients at risk of vascular complications. Additionally, preliminary data support the use of FDG PET/CT to follow therapy efficacy. FDG PET/CT allows early detection of inflammation, before morphological and irreversible vascular changes can be observed, allowing prompt diagnosis and treatment of LVV.

[Characteristics of giant cell arteritis patients under and over 75-years-old: A comparative study on 164 patients]

PURPOSE

Giant cell arteritis (GCA) is the most common vasculitis of the elderly. In order to assess the impact of age at diagnosis, we compared the characteristics of patients of less than 75 years (<75 years), to those of the 75 years and over (≥75 years).

PATIENTS AND METHODS

We conducted a retrospective study on 164 patients with GCA diagnosed from 2005 to 2017. All patients had at least 3/5 of the ACR criteria and had a CT-scan at diagnosis. The mean age was of 73±9.6 years. The age was<75 years for 84 patients (59 women) and≥75 years for 80 patients (53 women).

RESULTS

Patients≥75 years had more cardiovascular underlying diseases (P=0.026), a higher rate of hypertension (P=0.005) and more ophthalmic complications (P=0.02). They had less large vessel involvement (P<0.001), showed lower biological inflammatory reaction and had a more frequently positive temporal artery histology (P=0.04). The oral initial dose of corticosteroids did not differ between the groups. Corticosteroids pulse therapy was more frequent in patients≥75 years (P=0.01). The frequency of anti-platelet agents use was similar in the two groups. Relapse rate, corticodependance and the rate of corticosteroids weaning were similar in both groups.

CONCLUSION

Patients≥75 years at diagnosis of GCA were at lower risk of aortitis but were more likely to suffer from ophthalmic complications and to receive corticosteroid pulse therapy.

Aortic dilatation in patients with large vessel vasculitis: A longitudinal case control study using PET/CT

OBJECTIVE

To evaluate aortic diameter and predictors of aortic dilatation using ¹⁸FDG-PET/CT in a longitudinally followed cohort of patients with large vessel vasculitis (LVV) compared with controls.

METHODS

All consecutive patients with LVV who underwent at least 2 PET/CT scans between January 2008 and May 2015 were included. The first and last PET/CT study was evaluated by a radiologist and a nuclear medicine physician. Diameter and FDG uptake of the aorta was measured at 4 different levels: ascending, descending thoracic, suprarenal and infrarenal abdominal aorta. Twenty-nine age- and sex-matched patients with lymphoma who underwent at least 2 PET/CT scans in the same time interval were selected as controls.

RESULTS

93 patients with LVV were included in the study. In the time interval between first and last PET/CT study (median time 31 months), the diameter of the ascending, descending thoracic and suprarenal abdominal aorta significantly increased in LVV patients but not in controls. At last PET/CT, patients with LVV compared with controls had higher diameter of ascending [35.41 (5.54) vs 32.97 (4.11) mm, p = 0.029], descending thoracic [28.42 (4.82) vs 25.72 (3.55) mm, p = 0.007] and suprarenal abdominal aorta, mean [25.34 (7.01) vs 22.16 (3.26) mm, p = 0.005] and more frequently had aortic dilatation [19% vs 3%, p = 0.023]. Significant predictors of aortic dilatation were male sex [OR 7.27, p = 0.001] and, only for GCA, hypertension [OR 6.30, p = 0.031]. Finally, GCA patients with aortic FDG uptake grade 3 at first PET/CT, compared to those with aortic FDG uptake ≤2, had significantly higher aortic diameter.

CONCLUSIONS

Patients with LVV are at increased risk of aortic dilatation compared with age- and sex-matched controls. Significant predictors of aortic dilatation are male sex and, only for GCA, hypertension. GCA patients with aortic FDG uptake grade 3 are at increased risk of aortic dilatation.

Pathogenesis of giant-cell arteritis: how targeted therapies are influencing our understanding of the mechanisms involved

GCA is a chronic granulomatous vasculitis that affects large- and medium-sized vessels. Both the innate and the adaptive immune system are thought to play an important role in the initial events of the pathogenesis of GCA. Amplification cascades are involved in the subsequent development and progression of the disease, resulting in vascular inflammation, remodelling and occlusion. The development of large-vessel vasculitis in genetically modified mice has provided some evidence regarding potential mechanisms that lead to vascular inflammation. However, the participation of specific mechanistic pathways in GCA has not been fully established because of the paucity and limitations of functional models. Treatment of GCA is evolving, and novel therapies are being incorporated into the GCA treatment landscape. In addition, to improve the management of GCA, targeted therapies are providing functional proof of concept of the relevance of particular pathogenic mechanisms in the development of GCA and in sustaining vascular inflammation.

Large-vessel giant cell arteritis: diagnosis, monitoring and management

GCA is a chronic, idiopathic, granulomatous vasculitis of medium and large arteries. It comprises overlapping phenotypes including classic cranial arteritis and extra-cranial GCA, otherwise termed large-vessel GCA (LV-GCA). Vascular complications associated with LV-GCA may be due, in part, to delayed diagnosis, highlighting the importance of early identification and prompt initiation of effective therapy. Advancements in imaging techniques, including magnetic resonance angiography, CT angiography, PET and colour duplex ultrasonography, have led to improvements in the diagnosis of LV-GCA; however, the role imaging modalities play in the assessment of disease activity and long-term outcomes remains unclear. Glucocorticoids are the mainstay of therapy in LV-GCA, but their prolonged use is associated with multiple, sometimes serious, adverse effects. Recent data suggest that biologic therapies, such as tocilizumab, may be effective and safe steroid-sparing options for patients with GCA. However, data specifically evaluating the management of LV-GCA are limited.