What is the treatment for Takayasu arteritis?

Takayasu Arteritis: Overview of Symptoms and Diagnosis

Clinical Presentation

Takayasu arteritis presents in two distinct phases: an early inflammatory phase with constitutional symptoms, followed by a chronic occlusive phase with symptoms related to vascular stenosis or occlusion. 1

Early Inflammatory Phase

• Constitutional symptoms including fever, fatigue, weight loss, and malaise that precede vascular manifestations by months to years 2, 1
• Non-specific symptoms make early diagnosis challenging and require high clinical suspicion 2
• Predominantly affects women (10:1 female-to-male ratio) and typically presents in the third decade of life 3

Chronic Occlusive Phase

• Limb claudication from arterial stenosis or occlusion 3
• Diminished or absent pulses, particularly in the upper extremities 3
• Blood pressure discrepancies >10 mmHg between arms 3
• Vascular bruits, especially over subclavian arteries and aorta 3
• Renovascular hypertension from renal artery stenosis, occurring in up to 60% of patients in certain populations 4
• Cerebrovascular symptoms including stroke or transient ischemic attacks 2
• Cardiac manifestations including aortic regurgitation and coronary ischemia 2
• Visual disturbances from retinal ischemia 2

Geographic Distribution Patterns

• Japanese type: affects thoracic aorta and great vessels 3
• Indian type: affects abdominal aorta and renal arteries 3

Diagnostic Approach

Initial Laboratory Assessment

Begin with erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) to establish baseline inflammatory markers, though these are imperfect indicators of disease activity 3, 5

Imaging Studies

The initial evaluation should include thoracic aorta and branch vessel computed tomographic (CT) imaging or magnetic resonance imaging (MRI) to investigate possible aneurysm or occlusive disease. 3

First-Line Imaging Modalities

• CT angiography or MR angiography provide information about vascular wall inflammation and are preferred over catheter-based angiography for disease activity assessment 5, 6
• 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) shows supra-physiologic uptake in inflamed arterial walls and is valuable for diagnosis and monitoring 5, 6
• MR angiography has largely replaced conventional angiography for initial diagnosis in recent years 6

Imaging Findings Suggestive of Active Disease

• Vascular edema, contrast enhancement, and increased wall thickness on MR or CT angiography 5
• Supra-physiologic FDG uptake in the arterial wall on PET imaging 5
• New stenosis or vessel wall thickening in previously unaffected territories 5

Role of Conventional Angiography

• Digital subtraction arteriography remains the gold standard for definitive diagnosis of Takayasu arteritis 2
• Catheter-based angiography should be reserved for determining central blood pressures, surgical planning, or when noninvasive modalities are inadequate 5
• Angiography provides topographical classification that correlates with symptoms and prognosis 1

Diagnostic Criteria

The 1990 American College of Rheumatology criteria support diagnosis when 3 or more of the following are present: 3

• Age of onset <40 years
• Limb claudication
• Diminished brachial artery pulse
• Subclavian or aortic bruit
• Blood pressure difference >10 mmHg between arms
• Angiographic evidence of aorta or branch vessel stenosis

Comprehensive Vascular Assessment

A thorough clinical and imaging assessment of the entire arterial tree is recommended when Takayasu arteritis is suspected, as the disease can affect multiple vascular territories simultaneously 5

Monitoring Disease Activity

Clinical Monitoring

Long-term clinical monitoring is strongly recommended for all patients with Takayasu arteritis, even in apparent remission, given the potential for catastrophic outcomes without surveillance 5

Laboratory Monitoring

Clinical monitoring should be supported by measurement of inflammatory markers (ESR/CRP), though these are imperfect and can be nonspecific 5

Imaging Surveillance

Regularly scheduled noninvasive imaging in addition to routine clinical assessment is conditionally recommended, as vascular changes can occur during clinically quiescent disease 5

• Optimal imaging intervals are not well-established but typically range from every 3-6 months or longer 5
• Intervals may be shorter early in disease course and longer with established, quiescent disease 5

Common Diagnostic Pitfalls

• Failing to recognize the non-specific nature of early symptoms leads to delayed diagnosis and progressive vascular damage 2
• Relying solely on inflammatory markers to assess disease activity, as Takayasu arteritis can remain active at a subclinical level despite normal markers 5
• Assuming clinical remission based on symptoms alone without imaging confirmation, as vascular progression can occur asymptomatically 5
• Delaying imaging studies while pursuing other diagnoses for constitutional symptoms in young women 2
• Not assessing blood pressure in all four extremities during initial evaluation 3