Takayasu Arteritis
The autoimmune disease characterized by differential blood pressures and pulses in all extremities is Takayasu arteritis (TAK), a chronic granulomatous vasculitis affecting the aorta and its major branches that predominantly occurs in young women. 1
Clinical Presentation and Diagnostic Features
Takayasu arteritis classically presents with absent or diminished pulses in multiple extremities, earning it the designation "pulseless disease" in Western countries. 2 The disease causes stenosis, obstruction, or aneurysmal dilation of large vessels, leading to characteristic findings of:
- Differential blood pressures between extremities - a hallmark finding that should prompt immediate consideration of TAK 1
- Absent or diminished pulses in the upper extremities, particularly affecting brachial and radial arteries 3
- Subclavian steal syndrome from proximal subclavian artery occlusion, causing reversal of vertebral artery flow 3
- Constitutional symptoms including fatigue, fever, and weight loss during active disease phases 4
Epidemiology and Patient Demographics
TAK predominantly affects young women, typically under 40 years of age, with higher prevalence in Asian and Latin American populations. 4, 2 However, recognition is increasing in European populations. 4 The disease shows genetic predisposition with HLA-A24-B52-DR2 haplotype association in Japanese patients. 2
Essential Diagnostic Workup
Clinical monitoring in TAK specifically requires obtaining 4-extremity blood pressures as a standard assessment tool. 1 This is explicitly defined in the 2021 ACR/Vasculitis Foundation guidelines as part of routine disease monitoring.
Laboratory Findings
- Elevated inflammatory markers (ESR, CRP) are common but do not always correlate with active vessel wall inflammation 1, 4
- Normocytic anemia may be present 3
Imaging Studies (in order of diagnostic utility)
- Angiography remains the gold standard for evaluating vascular lesions 5
- CT angiography and MR angiography provide crucial information for early diagnosis and disease activity assessment 5, 3
- 18F-FDG-PET can detect metabolic activity in vessel walls before structural changes occur 5, 6
- Vascular ultrasound for accessible vessels 1
Life-Threatening Complications
Untreated TAK leads to severe morbidity and mortality through:
- Vision loss or blindness from retinal ischemia 1, 4
- Cerebrovascular ischemia and stroke 1, 4
- Cardiac ischemia and congestive heart failure 1, 4
- Limb ischemia 1
- Pulmonary thrombosis 4
- Aortic regurgitation 4
Treatment Approach
Initial Therapy
Glucocorticoids remain the cornerstone first-line treatment for TAK, with high-dose oral prednisone (1 mg/kg/day up to 80 mg) or IV pulse methylprednisolone (500-1000 mg/day for 3-5 days) for severe disease. 1
Steroid-Sparing Agents
Immunosuppressive therapy should be added early, particularly for refractory disease or to minimize glucocorticoid exposure. 1 Options include:
Biologic Therapy
Anti-TNF agents and tocilizumab are increasingly used for refractory cases that fail conventional immunosuppression. 1, 5
Surgical Intervention
Revascularization procedures (angioplasty, stenting, bypass grafting) should be performed during disease remission when possible to minimize restenosis risk. 1, 5
Critical Clinical Pitfall
The most dangerous pitfall is dismissing upper extremity symptoms in young women as musculoskeletal or psychosomatic complaints. 3 Any young female presenting with:
- Unilateral upper extremity pain, numbness, or paresthesia aggravated by activity
- Syncope or presyncope
- Lightheadedness or vertigo
- Unequal blood pressures between arms (>10 mmHg difference)
Must have bilateral arm blood pressures measured and pulses carefully palpated in all four extremities. 1 A single absent pulse or significant blood pressure discrepancy warrants immediate vascular imaging. 3