Conventional and CT angiographic diagnosis of Takayasu arteritis

Application of the 2022 ACR/EULAR criteria for Takayasu arteritis to previously diagnosed patients based on the 1990 ACR criteria

OBJECTIVES

Recently, a joint group of the American College of Rheumatology (ACR) and the European Alliance of Associations for Rheumatology (EULAR) proposed new criteria for Takayasu arteritis (TAK) (the 2022 ACR/EULAR criteria). This study applied the 2022 ACR/EULAR criteria to patients with previously diagnosed TAK based on the 1990 ACR criteria and investigated the concordance rate between the two criteria according to the four imaging modalities.

METHODS

This study reviewed the medical records of 179 patients who met the 1990 ACR criteria for TAK. The imaging modalities included conventional angiography, computed tomography angiography, fluorodeoxyglucose-positron emission tomography, and magnetic resonance angiography.

RESULTS

Regardless of the imaging modalities, the concordance rate between the two criteria was 85.5% when including all patients, whereas it increased to 98.1% when only patients aged ≤60 years were included. Among the four imaging modalities, computed tomography angiography exhibited the highest concordance rate between the two criteria (85.6%). The concordance rate among patients aged >60 years was 95.7%. Only one patient aged 50-60 years was reclassified as having both TAK and giant cell arteritis.

CONCLUSIONS

The concordance rate was 85.5% regardless of the imaging modalities and increased to 86.9% on simultaneous computed tomography angiography and fluorodeoxyglucose-positron emission tomography imaging.

Takayasu's Disease With Bilateral Carotid Arteritis in a Caucasian Female: A Rare Presentation and Diagnostic Dilemma

Takayasu arteritis (TAK) is not an uncommon cause of vasculitis in Caucasian females, however, involvement of bilateral carotid artery is a very rare presentation. We are presenting a 31-year-old young Caucasian female who presented with left-sided neck pain, headache and was subsequently found to have vasculitis of bilateral carotid arteries.

Application progress of multiple imaging modalities in Takayasu arteritis

Takayasu arteritis (TA) is a chronic, idiopathic, granulomatous large vessel vasculitis of unknown etiology. The clinical manifestations of TA are incredibly variable, mainly depending on the location of the lesions. In the light of its insidious progress and the diversity of clinical manifestations, a substantial proportion of patients might experience a considerable delay in diagnosis, which leads to irreversible malignant complications, highlighting the importance of early diagnosis. There has been accumulating evidence that early identification of disease is pivotal to initiate timely therapy and ameliorate the prognosis. Therefore, this review discusses and summarizes the latest evidence on the application progress of multiple imaging modalities.

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.

Biomarkers in Vasculitides of the Nervous System

Besides being affected by the rare and severe primary angiitis of the central nervous system (PACNS) the nervous system is also affected by primary systemic vasculitides (PSV). In contrast to PACNS, PSV affect not only the central but also the peripheral nervous system, resulting in a large array of potential symptoms. Given the high burden of disease, difficulties in distinguishing between differential diagnoses, and incomplete pathophysiological insights, there is an urgent need for additional precise diagnostic tools to enable an earlier diagnosis and initiation of effective treatments. Methods available to date, such as inflammatory markers, antibodies, cerebrospinal fluid (CSF) analysis, imaging, and biopsy, turn out to be insufficient to meet all current challenges. We highlight the use of biomarkers as an approach to extend current knowledge and, ultimately, improve patient management. Biomarkers are considered to be useful for disease diagnosis and monitoring, for predicting response to treatment, and for prognosis in clinical practice, as well as for establishing outcome parameters in clinical trials. In this article, we review the recent literature on biomarkers which have been applied in the context of different types of nervous system vasculitides including PACNS, giant-cell arteritis, Takayasu's arteritis, polyarteritis nodosa, ANCA (anti-neutrophil cytoplasm antibody)-associated vasculitides, cryoglobulinemic vasculitis, IgA vasculitis, and Behçet's disease. Overall, the majority of biomarkers is not specific for vasculitides of the nervous system.

Evaluation of takayasu arteritis with delayed contrast-enhanced MR imaging by a free-breathing 3D IR turbo FLASH

The primary aim of our case-control study was to observe delayed contrast-enhanced magnetic resonance imaging (DCE-MRI) in patients with Takayasu arteritis (TA) in comparison with magnetic resonance angiography (MRA). Twenty-seven patients including 15 with active TA and 12 with stable TA who underwent both aortic MRA and DCE-MRI were included. A total of 27 sex- and age-matched healthy volunteers were enrolled as the control group. MRA were obtained with T1WI-volume-interpolated breath-hold examination sequence or fast low-angle shot (FLASH) sequence. DCE-MRI was acquired with a free-breathing three-dimensional inversion recovery Turbo fast low-angle shot (3D IR Turbo FLASH). Neither stenosis nor delayed enhancement of arterial wall was shown in the control group. In patients with stable TA, arterial stenosis was observed on MRA. On DCE-MR, delayed enhancement of arterial walls could be observed in the active TA group but not in the stable TA group or the control group. Stenotic arteries on MRA were comparable in the active TA and stable TA (χ = 2.70, P = .259); however, delayed enhancement of arterial walls in the active-TA group were more than those in the stable group (χ = 27.00, P < .001). Our results suggest that DCE-MRI with the free-breathing 3D IR Turbo FLASH sequence could assess TA and delayed enhancement on DCE-MRI is one characteristics of the active TA.

Application of imaging techniques for Takayasu arteritis

Arterial injury with subsequent remodelling and predisposition to arterial stenosis and/or dilation are the hallmarks of Takayasu arteritis. The degree of arterial damage closely aligns with prognosis and therefore its prevention is the predominant aim of therapy. Non-invasive imaging has greatly improved our ability to identify the extent and severity of disease and to monitor its progress. However, many questions remain concerning the optimal use of individual modalities at different stages of disease. Imaging methods for the quantification of arterial damage are lacking. Likewise, no single technique can accurately determine disease activity within the arterial wall or distinguish inflammatory and non-inflammatory disease progression. The aim of this review is to outline current imaging strategies in Takayasu arteritis, their individual roles in diagnosis and disease monitoring and potential future advances.

Vessel Wall Inflammation of Takayasu Arteritis Detected by Contrast-Enhanced Magnetic Resonance Imaging: Association with Disease Distribution and Activity

AIMS

The assessment of the distribution and activity of vessel wall inflammation is clinically important in patients with Takayasu arteritis. Magnetic resonance imaging (MRI) is a useful tool, but the clinical utility of late gadolinium enhancement (LGE) in Takayasu arteritis has yet to be determined. The aim of the present study was to evaluate the utility of LGE in assessing vessel wall inflammation and disease activity in Takayasu arteritis.

METHODS AND RESULTS

We enrolled 49 patients with Takayasu arteritis who had undergone 1.5 T MRI. Patients were divided into Active (n = 19) and Inactive disease (n = 30) groups. The distribution of vessel wall inflammation using angiography and LGE was assessed by qualitative analysis. In 79% and 63% of patients in Active and Inactive groups, respectively, greater distribution of vessel wall inflammation was observed with LGE than with conventional angiography. MRI values of pre- and post-contrast signal-to-noise ratios (SNR), SNR increment (post-SNR minus pre-SNR), pre- and post-contrast contrast-to-noise ratios (CNR), and CNR increment (post-CNR minus pre-CNR) were evaluated at arterial wall sites with the highest signal intensity using quantitative analysis of post-contrast LGE images. No statistically significant differences in MRI parameters were observed between Active and Inactive groups. Contrast-enhanced MRI was unable to accurately detect active disease.

CONCLUSION

Contrast-enhanced MRI has utility in detecting the distribution of vessel wall inflammation but has less utility in assessing disease activity in Takayasu arteritis.

Takayasu arteritis as a cause of arterial hypertension. Case report and literature review

We report a 16-year-old girl in whom Takayasu arteritis (TA) was manifested mainly by severe arterial hypertension on her right arm, which was detected during a routine examination at school. Her systolic blood pressure on the right arm was significantly higher than that on the left one. There was also a pressure difference between the right arm and legs. The pulse of the left external carotid artery and that of the left radial artery was absent. Vascular bruits over interscapular and right supra- and subclavian areas were heard on auscultation. The diagnosis of TA was confirmed by a spiral computed tomography angiography, which showed a thickened thoracic aortic wall and narrowing of its lumen. In addition, complete occlusion of the left common carotid artery and the left subclavian artery was observed.

CONCLUSION

The rarity of the disorder and the heterogeneous nature of its clinical manifestation predispose to a late diagnosis and delayed treatment. Our report highlights the fact that the condition can and does occur in a pediatric population in Europe and hence must be considered in patients presenting with suggestive symptoms and signs, especially in young patients with unexplained hypertension. Clinical suspicion and proper imaging are crucial for the correct diagnosis and management of patients with TA. A brief review of literature completes this report.

Pulmonary vasculitis in the intensive care unit

Pulmonary vasculitis can occur in apparent isolation, as part of a primary systemic vasculitis, or with an underlying systemic inflammatory autoimmune disorder. The presentation of pulmonary vasculitis in the intensive care unit (ICU) can be fulminant and will often overlap with more common disorders that affect the critically ill. Although diffuse alveolar hemorrhage (DAH) is the clinical feature that often initiates the concern for an underlying vasculitis, hemoptysis may not be apparent or its presentation can be mistaken for an alternative disease process. As a result, the diagnosis of pulmonary vasculitis in the ICU may be delayed or be completely unrecognized. A high level of suspicion is essential to obtain a timely diagnosis and for effective therapies to be implemented. There have been significant advances this past decade in diagnostic strategies as well as in the therapeutic options for patients with pulmonary vasculitis. We review here the clinical presentations, diagnostic strategies, and treatment options of the critically ill patients presenting with pulmonary vasculitis. The reader is referred to other resources for a more comprehensive review of specific vasculitic entities.

Takayasu arteritis in children and adolescents

Takayasu arteritis is a devastating vasculitis of the aorta and its major branches. The clinical manifestations in paediatric patients are less specific than in adults: in children the disease presents with fever, arthralgias and hypertension. Intramural inflammation results in narrowing of the blood vessel lumen and therefore hypoperfusion of the parenchyma. Conventional angiography is the gold standard diagnostic procedure. Corticosteroids, cyclophosphamide, MTX and biological therapies such as TNF-α blocking agents are treatment options.

Visceral Artery Interventions in Takayasu's Arteritis

Takayasu's arteritis is an idiopathic chronic inflammatory disease affecting the aorta, its major branches and the pulmonary arteries. It leads to stenosis, occlusion, dilatation, and aneurysm formation in the involved vessels. Visceral arterial involvement occurs in 11 to 68% cases. Steno-obstructive lesions are most commonly seen and are usually symptomatic. Dilative and aneurismal lesions are uncommon and, when present, are usually clinically silent. Renal arteries are most commonly involved (24 to 68%), resulting in renovascular hypertension, whereas mesenteric arterial involvement is seen in 11 to 28% cases and is usually clinically silent. The assessment of disease activity is of utmost importance in its management as revascularization is best performed in the inactive phase. The disease activity can be assessed by clinical, biochemical, or radiological markers. The primary objectives of treatment include the control of disease activity by drug therapy, pharmacologic control of blood pressure (BP), supportive management and revascularization (surgical or endovascular) of the symptomatic ischemic territory. Surgical treatment is challenging due to the diffuse nature of the disease and involvement of adjacent aortic walls. It has a high incidence of anastomotic aneurysm formation (12 to 14%) and graft failure (20 to 40%) over time. Endovascular therapy (usually in the form of balloon angioplasty) has specific technical and procedural issues, but is safe and effective in the control of hypertension with success rates ranging between 80 to 96%. The overall complication rates are low. The cumulative 5-year patency rate for the management of renal artery stenosis is 67%. The use of stents is usually restricted as a bailout to treat obstructive dissection after angioplasty, due to a variety of reasons as their use may adversely affect the long-term outcome of treatment. Angioplasty is less effective in relieving obstruction in the mesenteric arteries and the outcomes are also infrequently reported.

Multidetector CT angiography in Takayasu arteritis

OBJECTIVE

To analyse the spectrum of Takayasu's arteritis (TA) on multidetector CT angiography (MDCTA).

MATERIALS AND METHODS

A retrospective analysis of the MDCTA findings was performed on 15 patients clinically diagnosed as Takayasu's arteritis. The spectrum and incidence of imaging findings on CTA were compared to studies in literature on catheter angiography in Takayasu's arteritis. Laboratory parameters were available in nine patients. The disease was considered active if erythrocyte sedimentation rate (ESR) levels were elevated and 'C' reactive protein (CRP) was positive. An attempt was made to correlate disease activity with the imaging findings.

RESULTS

Ascending aorta, arch of aorta and descending thoracic aorta were involved in 14 out of 15 (93%) patients. The wall thickness varied between 1 and 10mm with maximal involvement in arch and descending thoracic aorta. Major neck vessels were involved in 11 (73%) patients with most pronounced changes seen in the brachiocephalic trunk, left common carotid artery (CCA) and left subclavian artery (SCA). Abdominal aorta and its branches were involved in all the 11 (100%) patients in whom abdominal CTA was performed. Celiac axis and SMA were involved in 10 (91%) and seven (64%) patients, respectively while renal artery stenosis was present in five (45%) patients. In six patients, ESR was elevated and CRP was positive indicating active disease. All patients in whom the laboratory parameters were available showed mural thickening in the aorta and at least one of the neck vessels except for one patient with inactive disease who had aortic mural thickening only.

CONCLUSION

MDCTA provides information about both the vessel wall and lumen in patients with Takayasu's disease.

[Large-vessel vasculitis. Imaging and interventional therapy]

Giant cell arteritis and Takayasu's arteritis are classified as primary large-vessel vasculitides. Inflammatory cell infiltrates and cytokines induce destruction and hyperplasia of the vessel wall, leading to stenoses or aneurysms. When extracranial large arteries are involved, there is often a similar clinical and radiologic disease pattern of an inflammatory aortic arch syndrome. Rare causes of large-vessel vasculitis include Behçet's disease, association with other autoimmune diseases, and infection. Depending on the localization, imaging is usually performed by means of duplex ultrasound, magnetic resonance imaging, computed tomography, or positron emission tomography. These imaging modalities are used not only to establish the diagnosis but also to determine the disease extent and activity and to perform follow-up in the course of medical therapy. Angiography offers the option to perform interventional therapy for vascular stenoses and occlusions.

CT angiography in pediatric extremity trauma: preoperative evaluation prior to reconstructive surgery

Computed tomographic angiography (CTA) is a noninvasive modality for evaluating the vascular system and planning treatment strategies. The goal of this study was to validate the clinical utility of CTA in assessment of suspected pediatric extremity traumatic vascular injury, prior to emergent and delayed reconstructive surgery. A retrospective review was performed of all operative patients under 18 years of age who underwent multidetector-row CTA for evaluation of suspected extremity vascular injury. Parameters investigated included age, type of injury, referral source, temporal relationship between the injury and the CTA, CTA findings, operations performed, intraoperative findings, and clinical outcome. Between January 2002 and September 2005, 10 pediatric patients (6 males/4 females; mean age 8 years old, range 3-17) sustained either blunt (N = 8) or penetrating (N = 2) trauma and underwent CTA of the upper (N = 5) or lower extremities (N = 5). A total of 30% (3/10) of patients were referred from the emergency department acutely, 50% (5/10) were referred from the inpatient wards subacutely, and 20% (2/10) were referred from the outpatient clinics electively. Half (N = 5) underwent CTA to evaluate need for vascular repair, whereas half (N = 5) underwent CTA to evaluate local vasculature for flap reconstruction. Overall, 40% (4/10) of CTA findings were normal, whereas 60% (6/10) revealed traumatic vascular injuries. Pertinent nonvascular findings included soft tissue defects (60%, 6/10), fractures (40%, 4/10), and contracture deformities (20%, 2/10). In all cases, procedures were completed without complications, and intraoperative findings confirmed those from CTA. At a mean follow-up of 28 months, all injuries have healed without complications. CTA is a reliable noninvasive modality to evaluate pediatric patients with suspected traumatic extremity vascular injury and to plan treatment strategies for both vascular repair and extremity reconstruction.

Delayed enhancement on computed tomography in abdominal aortic aneurysm wall

The purpose of this study was to evaluate delayed enhancement (DE) of the aortic wall of atherosclerotic aneurysms using computed tomography and to evaluate the relationships between DE and wall thickness of abdominal aortic aneurysm (AAA), diameter of AAA, serum levels of C-reactive protein (CRP) which indicate inflammation status, and pathological findings. Computed tomographic images of atherosclerotic AAA in 110 patients were studied between July 2001 and March 2003. Computed tomography (CT) scanning included unenhanced, enhanced early, and enhanced delayed phases. Pathological findings were obtained from 19 of the 110 patients. We determined DE of the AAA wall and assessed the association between DE and AAA wall thickness, AAA diameter, serum levels of CRP, and pathological findings. Delayed enhancement on CT was demonstrated in 66 of 110 patients with atherosclerotic AAA (60.0%). Patients with DE demonstrated significantly larger AAA diameter (4.8 +/- 0.9 versus 3.9 +/- 0.6 cm, P < 0.0001) and significantly higher levels of CRP (5.0 +/- 6.0 versus 2.3 +/- 2.9 mg/l, P = 0.033) than those patients without DE. Patients with DE also had significantly thicker and more severe atheroma and a tendency toward more prominent inflammation and vascularity in pathologic findings. There was no significant difference in wall thickness between AAA with and without DE (1.44 +/- 0.7 versus 1.24 +/- 0.22 mm, P = 0.352). Delayed enhancement on CT demonstrated in over half of atherosclerotic AAA may be associated with chronic inflammation by atherosclerosis.

Vasculitis in the gastrointestinal tract

The primary systemic vasculitides are a rare group of inflammatory disorders, where damage is directed against the blood vessels. They range in severity from acute self-limiting illness to chronic life and organ threatening diseases requiring long-term treatment with toxic immunosuppressive regimes. None of them have specific tests and few have hard diagnostic criteria. This review summarises the gastrointestinal features of these diseases, along with their general clinical and epidemiological features and the evidence available to guide in their management.

MDCT angiography of pediatric vascular diseases of the abdomen, pelvis, and extremities

Multi-detector-row computed tomography (MDCT) enables rapid, noninvasive, high-resolution, and three-dimensional imaging of pediatric vascular diseases. In this paper, we explore the adaptation of the MDCT angiographic principles to pediatric patients for vascular diseases of the abdomen, pelvis, and extremities. Special emphasis is placed on the practical aspects of how to perform these studies. Optimizations of scan parameters, contrast medium usage, radiation dose, and three-dimensional image processing are discussed in detail. We provide practical guidance on how to choose between MR angiography and CT angiography. Finally, we review important pediatric vascular diseases, categorized into traumatic injuries, inherited vascular diseases, congenital vascular diseases, vasculitides, and surgical planning and assessment. In each category, we discuss how CT angiography can be tailored to maximize its clinical benefits.

Undiagnosed Takayasu's arteritis mimicking an acute aortic dissection

Takayasu's arteritis (TA) is a vasculitis involving the aorta and its branches. We report a case of undiagnosed TA that presented to the Emergency Department with a chief complaint of chest pain and signs consistent with an aortic dissection.

The clinical and ocular manifestations of Takayasu arteritis

PURPOSE

To evaluate the clinical and ocular manifestations of Takayasu arteritis and the fundus fluorescein angiography (FFA) characteristics of Takayasu retinopathy (TR).

PATIENTS AND METHODS

Medical records and fundus fluorescein angiograms of 156 eyes of 78 patients with Takayasu arteritis were reviewed. Fundus FA using a wide-field fundus camera (60 degrees) was performed in 19 patients, and conventional angiography or spiral computed tomographic angiography was performed in all 78 patients.

RESULTS

The series included 67 female and 11 male patients; mean age at time of diagnosis was 26.7 years (range, 4-61 years). Hypertension was found in 44 (56.4%) patients, ischemic cerebrovascular symptoms in 18 (23.1%) patients, and amaurosis fugax in 20 (25.6%) patients. On fundus examination, no retinopathy was found in 87 (55.8%) eyes; hypertensive retinopathy was found in 48 (30.8%) eyes; and TR was found in 21 (13.5%) eyes. Patients with TR had carotid artery or aortic arch involvement, and patients with hypertensive retinopathy had involvement of the descending aorta or renal artery and sparing of the carotids. Best-corrected visual acuity in TR Stage 1 to 3 ranged from 20/15 to 20/30, but in Stage 4, it ranged from 20/200 to hand motions because of secondary ocular complications. On FFA, the arm-to-retina circulation time was prolonged in all 21 eyes with TR (mean, 22.7+/-8.9 seconds), but only 14 eyes showed delayed arteriovenous filling time, which was mainly found in chronic, moderate to severe TR, Stage 3 or 4. Arteriovenous anastomosis was found in all 12 eyes with Stage 3 and 4 TR.

CONCLUSIONS

Delayed arm-to-retina circulation time is shown in all cases of TR, but delayed arteriovenous filling time is mostly found in moderate and severe TR. During ophthalmic examination, the delay of arteriovenous filling time and formation of arteriovenous anastomosis must be examined carefully to prevent visual deterioration.

Diagnosis of vasculitis

Vasculitis is a process that results from the inflammation of blood vessels and can occur de novo or secondary to a variety of diseases or drugs. Clinical presentation depends on the size and distribution of vessels involved. Anti-neutrophil cytoplasmic antibodies (ANCA) have been shown to have variable sensitivity in making the diagnosis of specific vasculitic syndromes, therefore histological confirmation may be necessary. Angiography is a useful tool in evaluating disease of large and medium-sized vessels that are inaccessible or potentially dangerous to biopsy. New imaging modalities are becoming more useful in diagnosing vessel wall changes, particularly in large-vessel vasculitides. In clinical practice it is not always possible to classify or apply a specific label to a patient with vasculitis, but for appropriate patient management it is important to define the extent and severity of disease and to exclude underlying secondary causes.

Noninvasive cerebrovascular assessment of Takayasu arteritis

BACKGROUND AND PURPOSE

Despite prominent neurological symptoms reported in Takayasu arteritis (TA), a complete evaluation of the cerebral circulation has not been consistently performed. The purpose of this study is to describe MR angiography (MRA), color Doppler flow imaging, and transcranial Doppler (TCD) findings in the extracranial and intracranial cerebral arteries in TA.

METHODS

MRA, color Doppler flow imaging, and TCD were performed in 21 patients with TA. Intima-media thickness was measured in the common carotid artery. The correlation between noninvasive studies and panaorto-arteriography was examined for supraortic vessels. Cerebral angiography findings were compared with the noninvasive methods in 7 patients. Intracranial hemodynamic changes detected by TCD were compared with extracranial circulation lesions assessed by panaorto-arteriography.

RESULTS

Noninvasive vascular techniques showed at least 1 abnormality in the extracranial and/or intracranial cerebral arteries in 20 of 21 patients (95%). Both MRA and color Doppler flow imaging showed a substantial correlation in the ability to detect obstructive lesions in supra-aortic vessels compared with panaorto-arteriography. High-resolution ultrasonography displayed common carotid artery wall thickening in 5 vessels that were considered normal by arteriography. In 24% of patients, MRA and TCD showed abnormalities consistent with stenosis of the basal cerebral arteries. In 10 patients with severe extracranial circulation involvement (detected by arteriography), TCD displayed intracranial hemodynamic changes consisting of dampened or blunted waveforms with low pulsatility.

CONCLUSIONS

The comprehensive assessment of cerebral circulation in TA patients by noninvasive methods allowed the detection of a high rate of diverse vascular abnormalities in both extracranial and intracranial circulation.

Takayasu's arteritis: a cell-mediated large-vessel vasculitis

Takayasu's arteritis is an idiopathic, systemic inflammatory disease, typically involving the aorta and its main branches. Cell-mediated autoimmunity has been strongly implicated in its pathogenesis. Early or active-stage pathology consists of continuous or patchy granulomatous inflammation, which progresses to intimal and adventitial fibrosis and scarring of the media. Multiple focal or segmental stenoses result and aneurysms may occasionally occur. Clinical presentation is heterogeneous, ranging from asymptomatic to catastrophic. In some patients, constitutional signs and symptoms indicating a systemic inflammatory response are observed, usually in the early stages. Specific features reflect arterial involvement, and result from end-organ or limb ischemia; they include vascular, neurological, cardiac, and pulmonary manifestations. The course of Takayasu's arteritis usually extends for many years with varying degrees of activity. Takayasu's arteritis has a worldwide distribution, with the greatest prevalence in eastern countries. Women of reproductive age are preferentially affected, but the illness is being recognized with increasing frequency in males. Variable phenotypes are recently emerging in different ethnic groups. Diagnosis is based on clinical features and vascular imaging studies that document typical patterns of stenoses or aneurysms of the aorta and its primary branches. Assessment of the activity of Takayasu's arteritis is imprecise, in that clinical features and acute-phase reactants do not accurately reflect active blood vessel inflammation. High-dose corticosteroids alone or a cytotoxic agent in addition to a corticosteroid may be effective in treating active disease. Critical lesions may require correction by surgery or interventional radiology.

Takayasu's Arteritis

Takayasu's arteritis is a worldwide entity that requires astuteness for early diagnosis. The challenge for the practicing physician is to document active disease, not only to justify immunosuppressive therapy but also to determine the appropriate timing for surgical intervention. No single laboratory assay or imaging modality establishes disease activity, though T2-weighted magnetic resonance imaging, magnetic resonance angiography, and spiral computed tomographic angiography have shown potential in identifying acute inflammatory changes within the vessel wall. Treatment consists primarily of glucocorticoids, but cytotoxic agents such as methotrexate and cyclophosphamide may be added to treat recalcitrant disease. New immunomodulating agents such as leflunomide and tumor necrosis factor inhibitors require further study before they can be added to the treatment armamentarium.

Large vessel vasculitis (giant cell arteritis, Takayasu arteritis)

Giant cell arteritis and Takayasu arteritis are separate but similar idiopathic diseases clinically characterized by constitutional symptoms, shared surrogate markers of systemic inflammation and indistinguishable granulomatous pan-arteritis of large vessels. This review emphasizes and analyses changing perceptions about the diseases. Recent series suggest that aortic involvement in giant cell arteritis may be more common than was previously appreciated. The case for and against inflammatory arthritis in giant cell arteritis is discussed. Ethnic new geographical variation in Takayasu arteritis-disease expression is reviewed. New philosophies of treatment are presented for both diseases. Prognosis in giant cell arteritis and its relationship to treatment is analysed. The utility of the laboratory for diagnosis and monitoring disease activity is appraised for each.