Pathogenesis of Takayasu's arteritis: a 2011 update

Elevated chemokines concentration is associated with disease activity in Takayasu arteritis

BACKGROUND

Chemokines were seldom investigated in Takayasu arteritis (TA) patients. This study aimed to evaluate the plasma levels of chemokines and their association with disease activity, including C-C chemokine ligand (CCL) 2, CCL3, CCL11, CCL20, C-X-C chemokine ligand (CXCL) 8 and CXCL10.

METHODS

Chemokines were measured in 85 TA patients, and 28 age- and gender-matched healthy controls. The disease activity of these TA patients was assessed according to the National Institute of Health (NIH) criteria. The relationship between the plasma levels of chemokines and disease activity was analyzed.

RESULTS

Among the 85 TA patients, 24 (28.2%) patients had active disease according to the NIH criteria. Significantly increased levels of CCL2, CCL3, CCL20, CXCL8 and CXCL10 were observed in TA patients when compared to healthy controls, while increased levels of CCL2, CCL20, CXCL8 and CXCL10 in TA patients with active disease when compared to those with inactive disease (all p < 0.05). The plasma cut-off values of CCL2, CCL20, CXCL8 and CXCL10 were 309.6 pg/ml, 131.4 pg/ml, 4.7 pg/ml, and 282.1 pg/ml, which maximized the ability of disease activity assessment and had a sensitivity/specificity of 66.7%/67.2%, 54.2%/77.1%,70.8%/72.1%,83.3%/54.1%, respectively (p < 0.05). Among patients with negative erythrocyte sedimentation rate, C-reactive protein or high-sensitivity C-reactive protein, CCL2, CCL20, CXCL8, and CXCL10 still had a high-sensitivity to recognize patients in the active phase.

CONCLUSIONS

This study showed that the expression level of CCL2, CCL20, CXCL8 and CXCL10 was elevated in active TA patients, indicating that these chemokines might act as potential biomarkers in evaluating the disease activity.

Serum complement 3 is a potential biomarker for assessing disease activity in Takayasu arteritis

BACKGROUND

Takayasu arteritis (TA) is a rare disease, lacking convenient and feasible biomarkers to identify disease activity. We aimed to evaluate the value of complements in distinguishing active TA.

METHODS

Consecutive patients were enrolled from the prospective East China TA cohort from April 2008 to June 2019. Patients were divided into two groups according to their baseline Kerr score. The value of complements and other biomarkers in identifying disease activity were analysed with cluster analysis, ROC curves, and combined tests. An independent group of patients from July 2019 to December 2019 were employed to validate the results.

RESULTS

Of the enrolled 519 patients, 406 (72.2%) cases were identified as active disease. Higher erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), interleukin-6 (IL-6), and complement 3 (C3) levels were observed in the active group. Elevated C3 (≥ 1.085 g/L) had a high value to identify active TA with a sensitivity of 69.9%, specificity of 66.7%, and AUC of 0.715. Combining the CRP (≥ 10.65 g/L; sensitivity, 50.7%; specificity, 82.4%) and C3, the sensitivity could be improved to 85.1% in parallel test and the specificity could be improved to 94.1% in serial test. Validation was further performed to confirm the value of C3 for disease activity assessment. The accuracy of the parallel test of CRP and C3 in external validation with independent 53 TA cases was 72.73% with the AUC of 0.721.

CONCLUSION

Elevated C3 could effectively evaluate the disease activity of TA, and C3 combining with CRP could further improve the disease activity evaluation.

Pentraxin 3 is more accurate than C-reactive protein for Takayasu arteritis activity assessment: A systematic review and meta-analysis

Aims

Whether the circulating levels of pentraxin 3 (PTX3), an acute phase reactant (APR), are higher in active Takayasu arteritis (TAK), and if so, whether PTX3 is more accurate than C-reactive protein (CRP) in TAK activity assessment has been investigated in this study.

Study design

Research works such as PubMed, Embase, ScienceDirect, Cochrane Library, and two Chinese literature databases (CNKI and WanFang) were searched for studies conducted till August 30th, 2019. Two investigators searched the studies independently, who evaluated the quality of the study using the Newcastle–Ottawa scale (NOS) and extracted data. Pooled standard mean difference (SMD) and diagnostic indexes, with a 95% confidence interval (CI), were calculated using a random-effect model.

Results

Totally, 8 studies involving 473 TAK (208 active and 265 inactive TAK) patients and 252 healthy controls were eventually included in the meta-analysis. PTX3 level in the blood in active TAK patients were found to be higher than that in dormant TAK with pooled SMD of 0.761 (95% CI = 0.38–1.14, p<0.0001; I² = 68%, p of Q test = 0.003). And there was no publication bias. Among the 8 studies, 5 studies identified active TAK with both PTX3 and CRP. The pooled sensitivity, specificity, and AUC values of PTX3 in active TAK diagnosis were higher than those of CRP (0.78 [95% CI = 0.65–0.87] vs. 0.66 [95% CI = 0.53–0.77], p = 0.012; 0.85 [95% CI = 0.77–0.90] vs. 0.77 [95% CI = 0.56–0.90], p = 0.033; 0.88 [95% CI = 0.85–0.90] vs. 0.75 [95% CI = 0.71–0.79], p < 0.0001). It showed potential publication bias using Egger’s test (p of PTX3 = 0.031 and p of CRP = 0.047).

Conclusions

PTX3 might be better than CRP in the assessment of TAK activity. Yet, it should be cautious before clinical use for moderate heterogeneity and potential publication bias of the meta-analysis.

Complement as a Therapeutic Target in Systemic Autoimmune Diseases

The complement system (CS) includes more than 50 proteins and its main function is to recognize and protect against foreign or damaged molecular components. Other homeostatic functions of CS are the elimination of apoptotic debris, neurological development, and the control of adaptive immune responses. Pathological activation plays prominent roles in the pathogenesis of most autoimmune diseases such as systemic lupus erythematosus, antiphospholipid syndrome, rheumatoid arthritis, dermatomyositis, and ANCA-associated vasculitis. In this review, we will review the main rheumatologic autoimmune processes in which complement plays a pathogenic role and its potential relevance as a therapeutic target.

Role of Neutrophils in Systemic Vasculitides

Neutrophils and neutrophil extracellular traps (NETs) contribute to the pathogenesis of many autoimmune diseases, including vasculitis. Though neutrophils, and NETs, can break self-tolerance by being a source of autoantigens for autoantibodies in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, playing a key role in driving the autoimmune response, the role of neutrophils and NETs in large vessel vasculitis, including giant cell arteritis (GCA), is not well understood. In this review, we summarize the current insight into molecular mechanisms contributing to neutrophil-mediated pathology in small and medium vessel vasculitis, as well as provide potential translational perspectives on how neutrophils, and NETs, may partake in large vessel vasculitis, a rare disease entity of unclear pathogenesis.

Pathogenesis of liver injury in Takayasu arteritis: advanced understanding leads to new horizons

Liver injury in Takayasu arteritis (TA) is a rare phenomenon. Most symptoms are nonspecific, and the exact pathogenesis remains to be elucidated. Early diagnosis and new treatment methods are important for an improved prognosis. A summary of the clinical information and mechanistic analyses may contribute to making an early diagnosis and development of new treatment methods. A PubMed search was conducted using the specific key words “Takayasu arteritis” and “liver” or “hepatitis” or “hepatic”. Symptoms and treatment of TA with an accompanying liver injury were reviewed retrospectively. Many factors are presumed to be involved in the mechanism of TA with liver injury, including the immune response, genes, infections, and gut microbiota. There are several lines of evidence indicating that immune dysfunction is the main pathogenic factor that triggers granuloma formation in TA patients. However, the role of genetics and infections has not been fully confirmed. Recently, the gut microbiota has emerged as an essential component in the process. We reviewed in detail the current concepts that support the complex pathogenesis of TA accompanied by liver injury, and we presented recent theories from the literature. Finally, we discussed future research directions of liver injury in TA.

Pathogenesis of Giant Cell Arteritis and Takayasu Arteritis-Similarities and Differences

PURPOSE OF REVIEW

Giant cell arteritis (GCA) and Takayasu arteritis (TAK) are auto-inflammatory and autoimmune diseases with a highly selective tissue tropism for medium and large arteries. In both diseases, CD4⁺ T cells and macrophages form granulomatous lesions within the arterial wall, a tissue site normally protected by immune privilege. Vascular lesions can be accompanied by an extravascular component, typically an intense hepatic acute phase response that produces well-known laboratory abnormalities, e.g., elevated ESR and CRP. It is unclear whether GCA and TAK lie on a spectrum of disease or whether they represent fundamentally different disease processes.

RECENT FINDINGS

GCA and TAK share many clinical features, but there are substantial differences in genetics, epidemiology, disease mechanisms, response to treatment, and treatment complications that give rise to different disease trajectories. A significant difference lies in the composition of the wall-infiltrating immune cell compartment, which in TAK includes a significant population of CD8⁺ T cells as well as natural killer cells, specifying disparate disease effector pathways mediating tissue damage and vessel wall remodeling. Despite the similarities in tissue tropism and histomorphology, GCA and TAK are two distinct vasculitides that rely on separate disease mechanisms and require disease-specific approaches in diagnosis and management.

Associations between clinical features and therapy with macrophage subpopulations and T cells in inflammatory lesions in the aorta from patients with Takayasu arteritis

Takayasu arteritis (TAK) is a large-vessel granulomatous vasculitis; the inflammatory infiltration in arteries comprises macrophages, multi-nucleated giant cells, CD4⁺ and CD8⁺ T cells, γδ T cells, natural killer (NK) cells and neutrophils. However, it is unknown which subtype of macrophages predominates. This study aims to evaluate macrophages subpopulations in the aorta in TAK. Immunohistochemistry was performed in the aorta from TAK patients (n = 22), patients with atherosclerotic disease (n = 9) and heart transplant donors (n = 8) using the markers CD68, CD86, CD206, CD3, CD20 and CD56. Active disease was observed in 54·5% of patients and active histological lesions were found in 40·9%. TAK patients presented atherosclerotic lesions in 27·3% of cases. The frequency of macrophages, M1 macrophages, T, B and NK cells was higher in the aorta from TAK and atherosclerotic patients compared to heart transplant donors. In TAK, macrophages and T cells were the most abundant cells in the aorta, and the expression of CD206 was higher than CD86 (P = 0·0007). No associations were found between the expression of cell markers and active disease or with atherosclerotic lesions. In TAK patients, histological disease activity led to higher T cell counts than chronic fibrotic lesions (P = 0.030), whereas prednisone use was associated with lower T cell counts (P = 0·035). In conclusion, M1 macrophages were more frequent in TAK and atherosclerotic patients compared to heart transplant donors, while M2 macrophages dominated M1 macrophages in TAK. T cells were associated with histological disease activity and with prednisone use in TAK.

Cardiac valvular involvement of Takayasu arteritis

OBJECTIVE

This study aimed to investigate the imaging and serological features in Takayasu arteritis (TA) patients with valvular involvement and determine the relationship between them.

METHOD

This is a retrospective single-center study enrolled 103 TA patients fulfilling the American College of Rheumatology criteria. An independent medical chart review was performed by two senior rheumatologists from Beijing Anzhen Hospital, Capital Medical University. The logistic analysis was used to investigate the relationship between valvular involvement in TA patients and the imaging and serological features of them.

RESULTS

Sixty-six TA patients (64.08%) had cardiac valvular involvement in our study. Aortic insufficiency (62.12%) was the most common valvular involvement. Twelve (22.22%) patients developed heart failure. In patients with valvular involvement, the most common angiographic type was Numano type V, which was significantly higher than that in patients without valvular involvement (53.30% vs 32.43%, p = 0.044), followed by coronary involvement (28.79% vs 10.81%, p = 0.036) and Numano type IIb (21.21% vs 5.41%, p = 0.034). Serum levels of immunoglobulin A (2.84 ± 1.42 g/L vs 2.26 ± 0.97 g/L, p = 0.032) and immunoglobulin G (13.5 ± 4.71 g/L vs 11.42 ± 3.01 g/L, p = 0.015) were significantly higher in patients with valvular involvement. Numano type IIb is significantly related to moderate-severe aortic valvular regurgitation in TA patients (4.10 [1.03-16.33], p = 0.04). Elevated C-reactive protein (CRP) level is associated with moderate-severe mitral valve involvement in TA patients (p = 0.05, OR = 17.75, 95% CI 1.07-295.41).

CONCLUSIONS

CRP elevation and Numano type IIb are significantly related to different types of valvular involvement in TA patients. Key Points • The Numano types IIb and V were common in TA patients with valvular involvement. • CRP elevation and Numano type IIb are close related to valvular involvement in TA patient. • Echocardiogram screening and CRP level examination are reasonable to TA patients which might have valvular involvement.

A study on the risk factors of coronary artery disease in patients with Takayasu arteritis

Background

The aim of this study was to investigate the risk factors of Takayasu arteritis (TA) involving the coronary artery.

Methods

Patients with TA involving coronary artery were included in this study. According to the patients’ condition of coronary artery involvement, they were divided into two groups: group A: TA involved coronary artery disease [at least one coronary artery stenosis (≥50%)] and group B: TA did not involve coronary artery. A logistic regression model was used to analyze the risk factors of arteritis involving the patients’ coronary artery lesions.

Results

A total of 442 TA patients were included in this study. The patients were significantly older in group A than those patients in group B (52.54±11.17 vs. 37.73±12.72, P<0.001). The age of onset in group A was significantly older than those patients in group B (42.21±11.46 vs. 32.74±13.13, P<0.001). The patients in group A had a longer course of disease (P<0.001), larger BMI (P=0.002) and higher rates of smoking, drinking, diabetes, dyslipidemia (P<0.05) when compared with group B. The level of eGFR was significantly decreased and the UA and TG levels were significantly increased in group A when compared with group B(P<0.05). Besides, the risk factors for TA involving coronary artery included the age of TA onset (OR =1.143, 95% CI: 1.007–1.298, P=0.039), course of TA (OR =1.165, 95% CI: 1.025–1.324, P=0.020), and BMI (OR =1.100, 95% CI: 1.021–1.185, P=0.013).

Conclusions

The later the age of TA onset, the longer the course of TA onset and the more traditional risk factors associated with atherosclerosis, the more vulnerable patients are to coronary artery involvement and this may not be related to clinical disease activity.

Pulmonary artery involvement in Takayasu arteritis: a retrospective study in Chinese population

BACKGROUND

Takayasu's arteritis (TA) may involve the pulmonary artery, which signifies a poor prognosis. This study investigated the features of TA patients with pulmonary artery involvement.

METHODS

One hundred and twenty-six inpatients diagnosed with TA were retrospectively studied. The clinical data of TA patients with and without pulmonary artery involvement were compared. The imaging features of pulmonary artery lesions in TA patients were evaluated. The treatment responses of pulmonary artery lesions were described, and the drug regimens in different treatment response groups were compared.

RESULTS

Among the patients with TA, 15.9% showed associated pulmonary artery involvement. The disease durations were significantly longer in patients with pulmonary artery involvement than in those without (108.0 months (53.5, 222.0) vs. 36.0 months (12.0, 120.0); p = 0.038). Hemoptysis was more common in TA patients with pulmonary artery involvement than in those without (15.0%, 3 cases vs. 0.0%; p < 0.001). TA patients with disease duration longer than 5 years showed a 3.42-fold higher odds of pulmonary artery involvement than those with a disease duration of less than 5 years (adjusted odds ratio, 3.42 (95% confidence interval, 1.20-9.76); p = 0.02). The most common imaging manifestations of pulmonary artery involvement were stenosis and occlusion. Among the six patients who had good response to treatment of pulmonary artery lesions, five were treated with the interleukin-6 receptor antagonist tocilizumab.

CONCLUSIONS

TA patients with pulmonary artery involvement have a longer course of disease and more symptoms of hemoptysis. TA-related pulmonary artery lesions more commonly manifested as stenosis and occlusion. Tocilizumab may be effective for TA-related pulmonary vascular disease. Key Points • Disease duration longer than 5 years is associated with pulmonary artery involvement in TA. • Hemoptysis is a characteristic clinical symptom of TA with pulmonary artery involvement. • Tocilizumab may be more effective for pulmonary artery lesions of TA.

Giant Cell Arteritis versus Takayasu Arteritis: An Update

Giant cell arteritis (GCA) and Takayasu Arteritis (TAK) are two systemic granulomatous vasculitides affecting medium- and large-sized arteries. Similarities in GCA and TAK regarding the clinical presentation, the systemic inflammatory response and the distribution of the arterial lesions, have triggered a debate over the last decade about whether GCA and TAK represent two different diseases, or are age-associated different clinical phenotypes of the same disease. On the other hand, there are differences regarding epidemiology, several clinical features (eg, polymyalgia rheumatica in GCA) and treatment. The aim of this review is to present the latest data regarding this question and to shed some light on the differences and similarities between GCA and TAK regarding epidemiology, genetics, pathogenesis, histopathology, clinical presentation, imaging and treatment. The existing data in literature support the opinion that GCA and TAK are different clinical entities.

Pathophysiology and therapy of systemic vasculitides

Systemic vasculitides represent uncommon conditions characterized by the inflammation of blood vessels that can lead to different complex disorders limited to one organ or potentially involving multiple organs and systems. Systemic vasculitides are classified according to the diameter of the vessel that they mainly affect (small, medium, large, or variable). The pathogenetic mechanisms of systemic vasculitides are still partly unknown, as well as their genetic basis. For most of the primary systemic vasculitides, a single gold standard test is not available, and diagnosis is often made after having ruled out other mimicking conditions. Current research has focused on new management protocol and therapeutic strategies aimed at improving long-term patient outcomes and avoiding progression to multiorgan failure with irreversible damage. In this narrative review, authors describe different forms of systemic vasculitides through a review of the literature, with the aim of highlighting the current knowledge and recent findings on etiopathogenesis, diagnosis and therapy.

Identification of two major autoantigens negatively regulating endothelial activation in Takayasu arteritis

The presence of antiendothelial cell antibodies (AECAs) has been documented in Takayasu arteritis (TAK), a chronic granulomatous vasculitis. Here, we identify cell-surface autoantigens using an expression cloning system. A cDNA library of endothelial cells is retrovirally transfected into a rat myeloma cell line from which AECA-positive clones are sorted with flow cytometry. Four distinct AECA-positive clones are isolated, and endothelial protein C receptor (EPCR) and scavenger receptor class B type 1 (SR-BI) are identified as endothelial autoantigens. Autoantibodies against EPCR and SR-BI are detected in 34.6% and 36.5% of cases, respectively, with minimal overlap (3.8%). Autoantibodies against EPCR are also detected in ulcerative colitis, the frequent comorbidity of TAK. In mechanistic studies, EPCR and SR-BI function as negative regulators of endothelial activation. EPCR has also an effect on human T cells and impair Th17 differentiation. Autoantibodies against EPCR and SR-BI block the functions of their targets, thereby promoting pro-inflammatory phenotype.

Autoantibodies against endothelium have been recognized in Takayasu arteritis (TAK). Here the authors identify endothelial protein C receptor and scavenger receptor class B type 1 as major autoantigens in TAK, and find autoantibodies inhibit the negative regulation of endothelial activation.

Anti-interleukin-6 (tocilizumab) therapy in Takayasu’s arteritis: a real life experience

Background/aim

Tumour necrosis factor inhibitors and anti-interleukin-6 (anti-IL-6) therapies are increasingly being used in Takayasu’s arteritis (TA) patients who are unresponsive to corticosteroids ± conventional immunosuppressive agents. The aim of this study is to assess the efficacy and safety of anti-IL-6 (tocilizumab) therapy in refractory TA patients in real life.

Materials and methods

Fifteen TA patients (86.7% were female) who received at least 3 cycles of tocilizumab therapy were retrospectively assessed by clinical, laboratory, and radiological evaluations before and after tocilizumab therapy.

Results

The median (min–max) age of the patients at evaluation was 35 (20–58) years and the median disease duration from diagnosis was 24 (12–168) months. The median (min.–max.) duration of follow-up after tocilizumab was 15 (3–42) months. There was a significant decrease in erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and patient global visual analogue scale (VAS) scores of patients after tocilizumab therapy. The median (min.–max.) ESR was 26 (5–119) vs. 3 (2–49) mm/h, P = 0.02; CRP was 39.8 (2.4–149.0) vs. 7.9 (0–92.9) mg/L, P = 0.017; and patient global VAS was 50 (0–90) vs. 30 (0–60), P = 0.027, respectively. In 8 patients, ESR and CRP levels were in the normal range in the last control. Imaging modality results after tocilizumab were available for 9 patients; 8 patients were radiologically stable and regression was seen in 1 patient. Comparable imaging modality results before and after tocilizumab were available for 5 patients; 4 patients were radiologically stable and regression was seen in 1 patient. Radiological findings were consistent with laboratory responses. Glucocorticoid dosages decreased from a mean dosage of 16.2 (9.1) mg/day at baseline to 7.1 (3.8) mg/day (P = 0.001) at the last follow-up visit. There was no increase in the steroid dosage in any of the patients. All patients tolerated tocilizumab well.

Conclusion

Based on retrospective real life data, anti-IL-6 (tocilizumab) appears to be an effective and tolerable treatment option in refractory TA patients.

Elevated antistreptolysin O titer is closely related to cardiac mitral insufficiency in untreated patients with Takayasu arteritis

Background

The etiology of Takayasu arteritis (TA) is unknown; however, a possible relationship between streptococcal infection and TA has been proposed. This study aimed to identify the clinical features and cardiac valvular involvement in untreated TA patients with an elevated antistreptolysin O (ASO) titer.

Methods

In this retrospective study, the clinical characteristics and features of valvular involvement were compared in TA patients with or without an elevated ASO titer.

Results

Of the 74 untreated TA patients, 13 patients were found have elevated ASO titers (17.6%). Mitral insufficiency was the most common in patients with elevated ASO (69.2%, 9/13), followed by aortic valve insufficiency (46.2%, 5/13) and tricuspid insufficiency (46.2%, 5/13), which were no significantly different than that in normal ASO group. The proportions of moderate to severe mitral (30.8% vs 1.6%, p = 0.000) and tricuspid valve (15.4% vs 1.64%, p = 0.023) insufficiency in the ASO positive group were significantly higher than those in the ASO negative group. The odds of mitral regurgitation in patients with elevated ASO titers were 3.9 times higher than those in the group with normal ASO titers (p = 0.053, OR = 3.929, 95% confidence interval [CI]: 0.983–15.694). Furthermore, the risk of moderate to severe mitral insufficiency in patients with elevated ASO titers was 41.6 times higher than that in patients with normal ASO titers (p = 0.002, OR = 41.600, 95% CI: 3.867–447.559).

Conclusions

An increase in ASO titer is related to valvular involvement in TA and is closely linked to mitral insufficiency.

Childhood-onset Takayasu Arteritis

Childhood-onset Takayasu Arteritis (cTAK) is a rare, large-vessel type of vasculitis seen in children, mainly affecting the aorta and its major branches. Clinical manifestations are often severe and arise as a result of systemic and local inflammation, along with end-organ ischemia. Disease flares are common and the disease burden is high, with a significant rate of morbidity and mortality. Recent advances in understanding the underlying disease pathobiology resulted in the use of pathway-targeting agents, such as TNF- or IL-6 inhibitors with improved disease control. Nonetheless, the prognosis often remains guarded and the accrued damage is significant. This review aims at summarizing the recent evidence and observations regarding this condition, with a focus on pediatric publications.

Serum leptin, a potential predictor of long-term angiographic progression in Takayasu's arteritis

Aim

In patients with Takayasu's arteritis (TA), current biomarkers that properly reflect the progression of the vascular structure remain absent. We aimed to determine the serum leptin level to investigate its relationship with imaging changes and assess its value as a predictor for long‐term radiological progression.

Method

This study included 34 untreated TA patients and 40 age‐matched healthy controls. At baseline and during the 5‐year follow‐up, we assessed disease activity using Kerr's criteria and Indian Takayasu Clinical Activity Score (ITAS2010) and monitored laboratory biomarkers as well as imaging findings. Serum leptin levels were measured by enzyme‐linked immunosorbent assay.

Results

The baseline serum leptin levels were significantly higher in TA patients than in healthy controls. Leptin was significantly positively correlated with triglyceride and high‐density lipoprotein cholesterol levels and negatively correlated with fibrinogen and C‐reactive protein levels. Patients were subdivided into three groups based on their baseline leptin level. During a 5‐year follow‐up, patients in the high and medium leptin groups showed more radiological progression compared to those in the low leptin group. Cox proportional hazard regression analysis showed that a high serum leptin level was a positive predictor of radiological progression.

Conclusion

Leptin is a potential biomarker for assessing TA structural progression. Untreated patients with elevated serum leptin levels are at a higher risk of progression in the aorta. Thus, the leptin level can be a predictor of long‐term radiological progression.

Takayasu Arteritis with Dyslipidemia Increases Risk of Aneurysm

Low-density lipoprotein cholesterol (LDL-C) has been associated with the occurrence of abdominal aortic aneurysm. However, whether LDL-C elevation associated with aneurysms in large vessel vasculitis is unknown. The aim of this study is to investigate the clinical and laboratory features of Takayasu arteritis (TAK) and explore the risk factors that associated with aneurysm in these patients. This retrospective study compared the clinical manifestations, laboratory parameters, and imaging results of 103 TAK patients with or without aneurysms and analyzed the risk factors of aneurysm formation. 20.4% of TAK patients were found to have aneurysms. The LDL-C levels was higher in the aneurysm group than in the non-aneurysm group (2.9 ± 0.9 mmol/l vs. 2.4 ± 0.9 mmol/l, p = 0.032). Elevated serum LDL-C levels increased the risk of aneurysm by 5.8-fold (p = 0.021, odds ratio [OR] = 5.767, 95% confidence interval [CI]: 1.302-25.543), and the cutoff value of level of serum LDL-C was 3.08 mmol/l. The risk of aneurysm was 4.2-fold higher in patients with disease duration >5 years (p = 0.042, OR = 4.237, 95% CI: 1.055-17.023), and 2.9-fold higher when an elevated erythrocyte sedimentation rate was present (p = 0.077, OR = 2.851, 95% CI: 0.891-9.115). In this study, elevated LDL-C levels increased the risk of developing aneurysms in patients with TAK.

[Takayasu's arteritis and atherosclerosis]

INTRODUCTION

Chronic inflammatory diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), are accompanied by high cardiovascular morbidity and mortality secondary to accelerated and premature atherosclerosis. Atherosclerosis is correlated with chronic systemic inflammation independently of the factors for cardiovascular risk. Vasculitis of large arteries such as Takayasu's disease, are characterized both by chronic systemic inflammation and local parietal vascular inflammation.

METHODS

We prospectively analyzed in a case-control study, a group of 64 carriers of Takayasu's arteritis patients with a mean age of 41 years [±11.94], a group of 50 RA female patients aged 45 years [±10.27], and a control group with an average age of 44 years [±12.63]. We recorded classic cardiovascular risk factors and used the Framingham equation to calculate the risk. We measured the intima-media thickness (IMT) in the carotids and noted the presence of carotid, aortic and femoral atheroma.

RESULTS

The mean calculated cardiovascular risk was 3.5 % in the Takayasu's group. It was 4.4 % in the RA group, and 4.5 % in controls with no significant difference between the three groups (P=0.153). Subclinical atherosclerosis defined by IMT> 0.70mm and/or the presence of atheroma plaque was found in 87 % of Takayasu's patients versus 76 % of RA patients, (P=0.088) and 48 % of controls (P<0.001). Most atherosclerotic plaques were found in the Takayasu group. Compared to the control group the carotid intima-media thickness was significantly higher in the Takayasu group. The average IMT in the Takayasu group was 0.91mm [±0.368], 0.76mm [±0.151] for the PR group, and 0.71mm [±0.141] for controls.

DISCUSSION

Atherosclerosis observed in Takayasu's disease was accelerated and premature, occurring in young patients with a low overall cardiovascular risk. Recent data support the central role of inflammation in all stages of atherogenesis from endothelial dysfunction to plaque rupture. Systemic inflammation associated with local parietal inflammation observed in Takayasu's arteritis, appears to be responsible for accelerated and premature atherosclerosis. The results of our study and the literature review favor an active strategy for cardiovascular prevention in Takayasu's disease.

Refractory Takayasu arteritis successfully treated with rituximab: case-based review

Takayasu arteritis (TAK) is a subtype of the large-vessel vasculitis, affecting the aorta and its major branches. Although T cell-mediated autoimmunity is mainly involved in vascular inflammation, in recent years, accumulating evidence suggests the important role of B cells in the pathogenesis and effectiveness of B-cell-targeted therapy with rituximab (RTX), a chimeric anti-CD20 monoclonal antibody in refractory TAK. Herein, we report for the first time a case involving a 34-year-old man with TAK who was refractory to four different biologic agents, such as one selective T-cell co-stimulation modulator (abatacept), one anti-interleukin-6 receptor monoclonal antibody (tocilizumab), and two tumor necrosis factor-α inhibitors (infliximab and etanercept), but eventually achieved remission with RTX. He received a total of six courses of RTX, and doses of prednisolone and methotrexate were tapered without relapse. The current case provided further evidence to the potential role of RTX therapy in patients with refractory TAK, and its efficacy needs to be validated in a controlled trial.

YKL-40 as a new biomarker of disease activity in Takayasu arteritis

OBJECTIVE

To evaluate the role of YKL-40 as a biomarker of disease activity in patients with Takayasu arteritis (TA).

METHODS

The study included 40 patients diagnosed with TA between January 2017 and January 2018. 40 age and sex matched healthy controls were included. Serum levels of YKL-40, as well as IL-6, IL-8, IL-17, sCD163, VEGF, MMP-2, MMP-9, OPN, PTX-3 and IFN-γ, were detected at the base line and end of the 6-month follow-up. Modified Kerr criteria, in which MRA was performed instead of traditional angiography, was used a standard measure of disease activity. The association of the measured biomarkers with disease activity was analysed.

RESULTS

The serum levels of YKL-40, IL-6, IL-8, IFN-γ, MMP-2, MMP-9, PTX-3 and OPN were significantly higher in active disease than in inactive disease. Significant differences in the serum levels of YKL-40, IL-6 and PTX-3 were also observed according to the disease activity degree. Logistic analysis demonstrated that high YKL-40 levels and high IL-6 levels were independent risk factors for active disease. When YKL-40 was combined with IL-6, the specificity and sensitivity for detecting active disease were increased (87.6% and 70.4% respectively); similar findings were obtained when YKL-40 was combined with CRP (72.3% and 84.6% respectively). A predictive model of active disease using ESR, CRP, IL-6, PTX-3 and MMP-9 showed significantly improved diagnostic efficiency when YKL-40 was added to the model (sensitivity: 85.1%; specificity: 94.3%; NRI value: 12.4%; IDI value: 4.6%, p < 0.05).

CONCLUSIONS

Serum YKL-40 concentrations may be a useful biomarker of disease activity in TA.

Aortitis and aortic aneurysm in systemic vasculitis

The term "large-vessel vasculitis" refers to chronic inflammation affecting the elastic arteries, mainly aorta and its major branches. Large-vessel vasculitis affecting the aorta is termed as "aortitis." This leads to diffuse wall thickening, loss of elasticity, stenosis, occlusion, dissection, calcification or aneurysm formation. Vasculitis involving the aorta includes Takayasu arteritis (commonest large-vessel vasculitis in India), giant cell arteritis (GCA), the periaortitis spectrum (including inflammatory abdominal aortic aneurysm), rheumatic diseases and IgG4-related disease. It is important for physicians to be aware of the aortic manifestations of common vasculitis-so that clinically relevant aortic involvement is not missed. Also, it is equally important for surgeons to keep in mind that aortic aneurysms can have an inflammatory aetiology. The primary reason for this is the central role that immunosuppressive therapy plays in the management of inflammatory aortic aneurysms. Surgical or percutaneous interventions, when needed, are most likely to succeed when performed after activity control; perioperative steroids may be beneficial in select cases, and postoperative disease activity control is imperative.

Cerebral involvement in systemic vasculitides: Extracts from the guideline of the German neurological society

Cerebral vasculitis is a rare disorder but plays a major role in the differential diagnosis of stroke, encephalopathy and headache. This guideline was developed in order to support clinicians in the diagnosis and treatment of cerebral manifestations of systemic vasculitides and rheumatic diseases. It is based on a medline research and was developed in a modified Delphi process and approved by the involved societies. This article is an abridged and translated version of the guideline published in DGNeurologie: Berlit, P. & Krämer, M. DGNeurologie (2018) 1: 17. 10.1007/s42451-018-0001-y.

Vasculitis: Decade in Review

BACKGROUND

In the last decade, we have come to better understand and manage the vasculitides. The classification of vasculitides has been revised. Genome- wide association studies and linkage analyses have been undertaken in hope of better understanding the pathogenesis of vasculitides. Comprehensive genetic studies have highlighted new pathways that may guide us in more targeted therapies. Description of the monogenic forms of vasculitis, such as deficiency of adenosine deaminase type 2 (DADA2), Haploinsufficiency of A20 (HA20), have introduced a new perspective to vasculopathies, and introduced alternative treatments for these diseases.

CONCLUSION

In this review, the important discoveries in pathogenesis and consensus treatment recommendations from the past decade will be summarized.

Childhood-Onset Takayasu Arteritis (c-TA): Current and Future Drug Therapy

Childhood-onset Takayasu arteritis (c-TA) is the third most common systemic vasculitic disorder in children. Vascular stenosis is the main complication, and aneurysms are reported in 19-65% of cases, often in combination with stenotic lesions. Management of patients with c-TA is largely based on studies involving predominantly patients with adult-onset TA (a-TA). More widely used criteria for patients with c-TA have been devised by the joint European League Against Rheumatism, Pediatric Rheumatology International Trials Organization, and Pediatric Rheumatology European Society. Of the available imaging modalities, those that do not use radiation (color Doppler ultrasound and magnetic resonance angiogram) are preferred over ¹⁸F-labeled fluoro-2-deoxyglucose (¹⁸F-FDG) positron-emission tomography, computed tomography (CT), and CT angiogram in children. Remission rates have been reported to be lower in c-TA than in a-TA, and published mortality rates in c-TA range from 16 to 40%, which is much higher than reported in patients with a-TA. The usual drug therapy options include steroids plus steroid-sparing second-line immunosuppressants, such as mycophenolate, azathioprine, methotrexate, cyclophosphamide, and cyclosporine, along with antiplatelet agents. Interleukin-6 inhibitors such as tocilizumab, as well as the tumor necrosis factor inhibitors, are other aggressive therapeutic options. As yet, no randomized controlled trials have been conducted in c-TA.

Takayasu arteritis - epidemiology, pathogenesis, diagnosis and treatment

Takayasu disease belongs to the group of autoimmune vasculitis which most often affects the aorta and its branches. It is rare, and it mainly affects young women. Recent epidemiologic studies suggest that Takayasu arteritis is being increasingly recognized in Europe. The first symptoms are non-specific and an early diagnosis is difficult and requires clinical awareness and suspicion. Patients with Takayasu arteritis often present increased inflammatory markers, including C-reactive protein and erythrocyte sedimentation rate, but systemic inflammatory response does not always show a positive correlation with inflammatory activity in the vessel wall. Therefore, imaging studies play a principal role in diagnosis and control of the disease. Glucocorticoids remain the most effective and serve as a cornerstone first line treatment. Immunosuppressive drugs play an important role as well, and biological therapy is increasingly being included in the treatment. This article describes the epidemiology, pathophysiology, diagnostics and treatment of this rare disease, so as to alert clinicians because disease left untreated can lead to narrowing and even closure of vital blood vessels. The most common Takayasu arteritis complications include pulmonary thrombosis, aortic regurgitation, congestive heart failure, cerebrovascular events, vision degeneration or blindness, and hearing problems.

Imaging aortic wall inflammation

Inflammation affects the aortic wall through complex pathways that alter its biomechanical structure and cellular composition. Inflammatory processes that predominantly affect the intima cause occlusive disease whereas medial inflammation and degeneration cause aneurysm formation.

Aortic inflammatory pathways share common metabolic features that can be localized by smart contrast agents and radiolabelled positron emission tomography (PET) tracers. ¹⁸F-Fluorodeoxyglucose (¹⁸F-FDG) is a non-specific marker of metabolism and has been widely used to study aortic inflammation in various diseased aortic states. Although useful in detecting disease, ¹⁸F-FDG has yet to demonstrate a reliable link between vessel wall disease and clinical progression.

¹⁸F-Sodium fluoride (¹⁸F-NaF) is a promising biological tracer that detects microcalcification related to active disease and cellular necrosis within the vessel wall. ¹⁸F-NaF shows a high affinity to bind to diseased arterial tissue irrespective of the underlying inflammatory process. In abdominal aortic aneurysms, ¹⁸F-NaF PET/CT predicts increased rates of growth and important clinical end-points, such as rupture or the requirement for repair.

Much work remains to be done to bridge the gap between detecting aortic inflammation in at-risk individuals and predicting adverse clinical events. Novel radiotracers may hold the key to improve our understanding of vessel wall biology and how this relates to patients. Combined with established clinical and morphological assessment techniques, PET imaging promises to improve disease detection and clinical risk stratification.

High expression of S100 calgranulin genes in peripheral blood mononuclear cells from patients with Takayasu arteritis

BACKGROUND

Toll-like receptors (TLR) 1 to 4 are highly expressed in aorta. Activation of TLR4 causes transmural arteritis in Human temporal artery-SCID chimera model. Neither TLR-4 nor its ligands have been studied in TA patients as yet. Aim of this study was to examine the expression of TLR4 and its endogenous ligands in peripheral blood mononuclear cells (PBMCs) of patients with Takayasu arteritis (TA).

METHODS

mRNA expression of TLR4, RAGE and various endogenous TLR4 ligands were quantified in PBMCs of 24 TA patients and 19 sex and age matched healthy controls by real time PCR using specific primers and SYBR Green qPCR master mix. S100A8/A9 and S100A12 were measured in cell culture supernatant of PBMCs from TA patients and healthy controls, both in un-stimulated state as well as, after lipopolysaccharides (LPS) stimulated cultures for 4 h. Expression of S100A8/A9 in aortic tissues was assessed by immunohistochemistry.

RESULTS

The mRNA expression of S100A8, S100A9, S100A12 and TLR4 were higher, while expression of RAGE and HSP70 were lower in TA as compared to healthy controls. Induction with LPS led to increase in secretion of both S100A8/A9 and S100A12 levels in TA as well as healthy controls. The fold of induction, measured by LPS stimulated/unstimulated control was higher in healthy controls [2.88 (1.7-3.53) fold] as compared to TA [1.345 (1-1.82) fold]; p < 0.05. Numerically, S100A8/A9 was also higher in healthy controls [2.04 (1.7-5.6) fold] as compared to TA [1.38 (1.09-3.6) fold], but it didn't reach statistical significance; p = 0.129. Mild to moderate intensity expression of S100A8/A9 protein was noted in aortic tissues from patients with TA.

CONCLUSION

mRNA expression of TLR4 and its ligand S100A8, S100A9, and S100A12 in PBMCs of TA patients was higher as compared to healthy controls. LPS stimulation led to higher induction of S100A12 secretion in healthy controls as compared to TA. Expression of S100A8/A9 was detected in inflamed aortic tissues from patients with TA.

Ultrasound diagnosis and follow-up of Takayasu arteritis with femoral vein involvement

Takayasu arteritis (TA) is a form of chronic vasculitis that mainly affects the aorta and its main branches, most commonly in young female patients. The pathogenesis of the disease remains unclear, and the clinical manifestations are nonspecific. Therefore, misdiagnosis of the disease is considered to be common. Moreover, to the best of our knowledge, TA affecting veins has not been reported. Here we report a case of an adolescent with TA affecting the femoral vein as diagnosed by ultrasound.

Pathogenesis of large vessel vasculitis: Implications for disease classification and future therapies

Despite being recognised over a century ago, the aetiology and pathogenesis of large vessel vasculitis (LVV) still remains elusive. Takayasu’s arteritis (TA) and giant cell arteritis (GCA) represent the two major categories of LVV, each with distinctive clinical features. Over the last 10 years an increased understanding of the immunopathogenesis of the inflammatory cascade within the aortic wall has revived the view that LVVs may represent subtypes of the same pathological process, with implications in the treatment of this disease. In this review, the histological, genetic and immunopathological features of TA and GCA will be discussed and the evidence for a common underlying disease mechanism examined. Novel markers of disease activity and therapies based on advances in our understanding of the immunopathogenesis of these conditions will also be discussed.

Current and emerging therapies in large-vessel vasculitis

GCA shares many clinical features with PMR and Takayasu arteritis. The current mainstay of therapy for all three conditions is glucocorticoid therapy. Given the chronic, relapsing nature of these conditions and the morbidity associated with glucocorticoid therapy, there is a need for better treatment options to induce and sustain remission with fewer adverse effects. Conventional immunosuppressive treatments have been studied and have a modest effect. There is a keen interest in biologic therapies with studies showing the efficacy of IL-6 antagonists in PMR and GCA. Recently the first two randomized clinical trials in Takayasu arteritis have been completed. A major challenge for all of these conditions is the lack of standardized measures to assess disease activity. Long-term studies are needed to evaluate the impact of biologic therapies showing potential on important clinical outcomes such as vascular damage, cost-effectiveness and quality of life. The optimal duration of treatment also needs to be assessed.

Takayasu's disease effects on the kidneys: current perspectives

Takayasu arteritis (TA) is a chronic vasculitis disease of unknown etiology. Clinically significant renal disease is relatively common, and renovascular hypertension is the major renal problem. The assessment of TA activity is usually challenging because vascular inflammation may progress to fixed vascular injury without findings of active disease. Until now, the best therapeutic options have not been identified. This review highlights the current perspectives of renal involvement in TA.

Vasculitis Pathogenesis: Can We Talk About Precision Medicine?

Precision medicine is designing the medical care by taking into account the individual variability for each person. We have tried to address whether the existing data may guide precision medicine in primary systemic vasculitides (PSV). We have reviewed genome-wide association studies (GWAS) data, lessons from monogenic mimics of these diseases, and biomarker studies in immunoglobulin A vasculitis/Henoch–Schönlein purpura, Kawasaki disease, anti-neutrophil cytoplasmic antibody-associated vasculitis, polyarteritis nodosa (PAN), Takayasu arteritis, and Behçet’s disease (BD). GWAS provide insights about the pathogenesis of PSV while whole exome sequencing studies lead to discovery of monogenic vasculitides, phenotype of which could mimic other types of vasculitis such as PAN and BD. Monogenic vasculitides form a subgroup of vasculitis which are caused by single gene alterations and discovery of these diseases has enabled more specific therapies in these patients. With increasing number of studies on biomarkers, new targets for treatment appear and better and structured follow-up of PSV patients will become possible. Proteomics and metabolomics studies are required to better categorize our patients with PSV so that we can manage them appropriately and offer more targeted therapy.

Takayasu Arteritis Coexisting with Sclerosing Osteomyelitis

We report a rare case of a 27-year-old woman with Takayasu arteritis (TAK) complicated by diffuse sclerosing osteomyelitis. She first presented with sclerosing osteomyelitis of the right mandible without evidence of arteritis in the carotid arteries. Eight months later, she complained of left neck pain, and imaging studies revealed the presence of arteritis in the left carotid artery. She was diagnosed with TAK, and immunosuppressive treatment was initiated, which was effective for both the arteritis and the osteomyelitis. Osteomyelitis is an important complication of TAK and bone scintigraphy is useful for its detection.

Takayasu's arteritis associated with eosinophilic gastroenteritis, possibly via the overactivation of Th17

Background

Takayasu’s arteritis (TA) is a large-vessel vasculitis pathologically characterized by granulomatous necrotizing vasculitis with giant cells. Although the cause of TA is still unclear, genetic factors as well as immunological abnormalities, particularly the overactivation of Th1 and Th-17, are considered to play important roles in the pathogenesis of this disease. Eosinophilic gastroenteritis (EGE) is a type of refractory inflammation in which numerous eosinophils infiltrate the inflammatory area. It is known that the overactivation of Th2 is associated with the pathogenesis of EGE, although the cause of EGE is still unclear. The immunological abnormalities in TA are therefore thought to be different from those in EGE. To date, no cases of complication of TA and EGE have been reported.

Case presentations

An 18 year-old female was diagnosed with EGE and treated with prednisolone. At 6 months after completion of the treatment, the patient experienced chest pain, and was diagnosed with TA. TH1 and TH17 immunity are thought to be involved with TA, while TH2 are considered to be involved with EGE. In this case, the expression of IL-17 mRNA in the colon mucosa greatly decreased after prednisolone treatment for EGE.

Conclusions

This is the first report of TA complicated with EGE, and the overactivation of TH17 is considered to be associated with the pathogenesis of these two diseases.

Discrepancies between vascular and systemic inflammation in large vessel vasculitis: an important problem revisited

A lack of absolute correlation between systemic inflammation parameters and ongoing vascular disease activity is an important problem in some patients with large vessel vasculitis, especially Takayasu arteritis (TAK). Systemic and vascular wall inflammation in TAK are obviously interrelated, but sometimes they may act independently. There are clear discrepancies between these two types of inflammation, including cytokine patterns and responses to treatment. Vascular and systemic inflammation may also be discordant in two subgroups of giant cell arteritis. The first subgroup is mainly characterized by severe systemic inflammation mostly associated with IL-6-driven immunity, while in the second subgroup there is less systemic inflammation but prominent neuro-ophthalmic ischaemic complications characterized mostly by IFN-γ-mediated effects. Although no definite boundaries exist, it may be suggested that the IL-6/Th17/IL-17 pathway primarily drives systemic inflammation while the IL-12/Th1/IFN-γ pathway dominates in vascular wall inflammation both in TAK and giant cell arteritis. Immunosuppressive treatment of TAK (especially corticosteroids) initially suppresses systemic inflammation, while longer treatment duration is required for the suppression of vascular inflammation. Therefore, evaluating only the systemic inflammation may be misleading. Vascular wall inflammation is currently evaluated using expensive imaging methods, which are not feasible for repetitive use. Although pentraxin-3 is superior to erythrocyte sedimentation rate and CRP, we need more reliable biomarkers to reflect vascular wall inflammation in patients with TAK.

Pulmonary vasculitis: diagnosis and endovascular therapy

Pulmonary vasculitides are caused by a heterogeneous group of diseases with different clinical features and etiologies. Radiologic manifestations depend on the predominant type of vessel involved, which are grouped into large, medium, or small-sized vessels. Diagnosing pulmonary vasculitides is a challenging task, and radiologists play an important role in their management by providing supportive evidence for diagnosis and opportunities for minimally invasive therapy. This paper aims to present a practical approach for understanding the vasculitides that can affect the pulmonary vessels and lungs. We will describe and illustrate the main radiologic findings, discussing opportunities for minimally invasive treatment.

High Secretion of Interleukin-6 and Increased MINCLE Receptor Expression Upon Exposure to Mycobacterial Cord Factor Analog Trehalose-6, 6-Dibehenate (TDB) in Patients with Takayasu Arteritis

Introduction:

Suspicion on the association between Takayasu Arteritis (TA) and Tubcerculosis (TB) has been in vogue for years. Prevalence of TB in TA is reported to be higher. We aimed to study innate immune responses in patients with TA on exposure to Trehalose-6,6-dibehenate (TDB), a synthetic analogue of Trehalose-6,6-Dimycolate (TDM, also known as mycobacterial cord factor) in comparison with healthy controls.

Materials and Methods:

Patients with type V TA, satisfying 1990 ACR criteria, and age and sex matched healthy controls were recruited. PBMCs were cultured with 5µg/ml, 50µg/ml or without any TDB for 48 hours in RPMI medium inside a 5% Co2 incubator. IL-6, TNF-α and IL-17 were measured in cell culture supernatant, which was separated from the cells at the end of the incubation period. Gene expressions of IL-6, IL-8, TNFα, IFN-γ, MINCLE and BCL-10 were quantified in real time PCR using specific primers and SYBR green chemistry.

Results:

Twenty two TA patients and 21 healthy controls were recruited. Both patients and controls showed response by secreting IL-6 and TNF-α upon stimulation by TDB. Relative induction (TDB stimulated TA sample / unstimulated control) of IL-6 was significantly higher in TA [31.88(0.74-168)] patients as compared to healthy controls [1.931(0.644-8.21); p<0.002], when co-cultured with 50µg/ml TDB. The expression of MINCLE, the TDB receptor was higher in TA samples than healthy controls upon TDB stimulation.

Conclusion:

Stimulation with mycobacterial synthetic analogue led to higher secretion of IL-6 and higher expression of MINCLE in PBMCs of patients with TA as compared to healthy controls.

Takayasu arteritis and giant cell arteritis: are they a spectrum of the same disease?

Giant cell arteritis (GCA) and Takayasu arteritis (TAK) are forms of large-vessel vasculitides that affect the aorta and its branches. There is ongoing debate about whether they are within a spectrum of the same disease or different diseases. Shared commonalities include clinical features, evidence of systemic inflammation, granulomatous inflammation on biopsy, role of T-helper (Th)-1 and Th17 in the pathogenesis, and, abnormalities of the aorta and its branches on imaging. However, there are also several differences in the geographic distribution, genetics, inflammatory cells and responses to treatment. This review highlights the similarities and differences in the epidemiology, pathogenesis, clinical manifestations, imaging findings and treatment responses in these conditions. Current data supports that they are two distinct conditions despite the numerous similarities.

Biological treatments in giant cell arteritis & Takayasu arteritis

Giant cell arteritis (GCA) and Takayasu arteritis (TAK) are the two main large vessel vasculitides. They share some similarities regarding their clinical, radiological and histological presentations but some pathogenic processes in GCA and TAK are activated differently, thus explaining their different sensitivity to biological therapies. The treatment of GCA and TAK essentially relies on glucocorticoids. However, thanks to major progress in our understanding of their pathogenesis, the role of biological therapies in the treatment of these two vasculitides is expanding, especially in relapsing or refractory diseases. In this review, the efficacy, the safety and the limits of the main biological therapies ever tested in GCA and TAK are discussed. Briefly, anti TNF-α agents appear to be effective in treating TAK but not GCA. Recent randomized placebo-controlled trials have reported on the efficacy and safety of abatacept and mostly tocilizumab in inducing and maintaining remission of GCA. Abatacept was not effective in TAK and robust data are still lacking to draw any conclusions concerning the use of tocilizumab in TAK. Furthermore, ustekinumab appears promising in relapsing/refractory GCA whereas rituximab has been reported to be effective in only a few cases of refractory TAK patients. If a biological therapy is indicated, and in light of the data discussed in this review, the first choice would be tocilizumab in GCA and anti-TNF-α agents (mainly infliximab) in TAK.

Tocilizumab and refractory Takayasu disease: Four case reports and systematic review

BACKGROUND

Relapses upon corticosteroids tapering and immunosuppressive agents are frequent in Takayasu arteritis (TA). Interleukin-6 is highly involved in physiopathology of TA. Many reports showed efficacy of tocilizumab (TCZ) in refractory TA cases. We report four cases and an updated literature review on the TCZ efficacy and safety in patients with TA.

METHODS

Patients with TA defined by ACR 1990 criteria were included. Clinical, biological and imaging data were retrospectively reported. Disease activity was analyzed before TCZ and during the follow-up. Medline database was searched for systematic literature review.

RESULTS

One hundred and five patients (median age 28years [22-38]) were included, mostly refractory cases (76 patients, 72%). Median TCZ duration was 12months [6-20]. Among 105 patients, 90 patients (85.7%) had an initial clinical response within three months [3-6] and 43/66 patients (65.2%) had a radiological improvement. Only seven patients (9%) showed relapse on therapy. Corticosteroid dose reduction was obtained in 75/83 patients (90.4%). Relapse after TCZ discontinuation was observed in six patients (46%), with a median time of five months [2-9]. Twenty-four side-effects were noted in 18 patients (18%), with TCZ interruption in seven cases (7%): 10 infections, five cytopenia, six hepatitis, one pancreatitis, one cutaneous rash and one breast cancer.

CONCLUSIONS

This review confirms that TCZ is safe and effective in refractory cases of TA and TCZ is a corticosteroid-sparing therapy in patients with or without previous TNFα blockers therapy. However relapses after TCZ discontinuation are frequent.

Takayasu Arteritis

Takayasu arteritis is an idiopathic granulomatous vasculitis of the aorta and its main branches and it constitutes one of the more common vasculitides in children. Inflammation and intimal proliferation lead to wall thickening, stenotic or occlusive lesions, and thrombosis, while destruction of the elastica and muscularis layers originates aneurysms and dissection. Carotid artery tenderness, claudication, ocular disturbances, central nervous system abnormalities, and weakening of pulses are the most frequent clinical features. The diagnosis is usually confirmed by the observation of large vessel wall abnormalities: stenosis, aneurysms, occlusion, and evidence of increased collateral circulation in angiography, MRA or CTA imaging. The purpose of this revision is to address the current knowledge on pathogenesis, investigations, classification, outcome measures and management, and to emphasize the need for timely diagnosis, effective therapeutic intervention, and close monitoring of this severe condition.