12‑year‑old girl with hypertension and blood pressure asymmetry
A 12‑year‑old girl is brought to the clinic because of headaches and dizziness. On examination, her blood pressure in the right arm is 155/95 mm Hg, while in the left arm it is 130/80 mm Hg. The left radial pulse is weak and the right radial pulse is bounding. There is a bruit over the left carotid artery. The child has had fever, night sweats, and weight loss over the past 3 months.
BP 155/95 (R) vs 130/80 (L)Weak left radial pulseCarotid bruitConstitutional symptoms
❓ Q1. Identify the most likely diagnosis. List the key clinical features in this patient.
✅ Model Answer: • Diagnosis: Takayasu arteritis.
• Key clinical features:
- Hypertension: BP 155/95 mm Hg (right arm) – likely secondary to renal artery stenosis.
- Blood pressure asymmetry: 25 mm Hg difference between arms (>10 mm Hg is significant).
- Absent/diminished pulses: weak left radial pulse (pulseless disease).
- Vascular bruit: left carotid bruit – indicates arterial stenosis.
- Constitutional symptoms: fever, night sweats, weight loss – systemic inflammation.
❓ Q2. What is the significance of blood pressure asymmetry in this patient?
✅ Model Answer: • Blood pressure asymmetry (>10 mm Hg difference between arms):
- Clinical significance: suggests subclavian artery stenosis or occlusion (one of the hallmarks of Takayasu arteritis).
- Pathophysiology: large vessel vasculitis causes inflammation and stenosis of the aorta and its branches – subclavian involvement leads to decreased pressure distal to the stenosis.
- Diagnostic value: part of the EULAR/PRES criteria for Takayasu arteritis; should prompt vascular imaging (MRA/CTA).
- Management: four-limb BP should be measured in any child with hypertension to detect asymmetry.
❓ Q3. What is the pathogenesis of Takayasu arteritis?
✅ Model Answer: • Pathogenesis:
- Chronic granulomatous panarteritis: involves the aorta and its major branches.
- Immune-mediated: CD4+ T-cell infiltration, macrophages, and giant cells; leads to intimal hyperplasia and fibrosis.
- Stages: Acute (inflammatory) → chronic (fibrotic) stages.
- Vessels affected: aortic arch and its branches (subclavian, carotid), descending aorta, renal arteries, and mesenteric arteries.
- Complications: stenosis, occlusion, aneurysm formation, and thrombosis.
- Associated HLA: HLA-B*52, HLA-B*39.
❓ Q4. What diagnostic tests would you perform to confirm the diagnosis?
✅ Model Answer: • Diagnostic workup:
- Four-limb blood pressure measurement: to document asymmetry and hypertension.
- Inflammatory markers: ESR and CRP – usually elevated in acute phase.
- MRA with STIR sequence: imaging of choice – shows vessel wall edema, thickening, stenosis, and aneurysms.
- CTA: alternative imaging – shows luminal stenosis, wall thickening.
- PET-CT: demonstrates increased FDG uptake in vessel walls (active inflammation).
- Conventional angiography: reserved for cases where intervention is planned.
- EULAR/PRES criteria: used for diagnosis – requires typical angiographic findings + ≥1 clinical feature (hypertension, pulse deficit, BP asymmetry, bruit, constitutional symptoms, elevated acute phase reactants).
❓ Q5. What is the first-line treatment for Takayasu arteritis?
✅ Model Answer: • First-line treatment:
- Glucocorticoids: prednisone 1-2 mg/kg/day (maximum 60 mg/day) – the mainstay of therapy.
- Response: dramatic improvement in constitutional symptoms; ESR/CRP should normalize.
- Duration: high dose for 4-6 weeks, then taper slowly over 12-18 months.
- Steroid-sparing agents: methotrexate, azathioprine, mycophenolate mofetil added early to reduce steroid burden.
- Biologic therapy: tocilizumab (anti-IL-6) or TNF inhibitors (adalimumab, infliximab) – for refractory or steroid-dependent disease.
- Hypertension management: ACE inhibitors (first-line for renovascular hypertension), calcium channel blockers, beta-blockers.
❓ Q6. What is the role of tocilizumab in Takayasu arteritis?
✅ Model Answer: • Role of tocilizumab (anti-IL-6 receptor):
- Indication: used in refractory or steroid-dependent Takayasu arteritis.
- Mechanism: blocks IL-6 signaling, reducing inflammation and vascular damage.
- Efficacy: clinical trials show significant reduction in relapses and steroid-sparing effects.
- Dose: 8 mg/kg IV monthly (or 162 mg SC weekly for adults).
- Monitoring: watch for infections, elevated liver transaminases, lipid profile changes.
- Alternative: TNF inhibitors (infliximab, adalimumab) are also used in refractory cases.
❓ Q7. What complications may arise from Takayasu arteritis?
✅ Model Answer: • Complications:
- Hypertensive emergencies: severe renovascular hypertension may lead to hypertensive encephalopathy, seizures, or stroke.
- Stroke/TIA: due to carotid or vertebral artery involvement.
- Heart failure: due to uncontrolled hypertension or aortic regurgitation.
- Renal failure: from renal artery stenosis or malignant hypertension.
- Aneurysm formation: aortic root or descending aorta – risk of rupture.
- Myocardial infarction: due to coronary artery involvement (rare).
- Ischemic limb: claudication, gangrene (rare).
- Growth failure: chronic disease and malnutrition.
❓ Q8. How would you manage hypertension in this patient?
✅ Model Answer: • Hypertension management:
- First-line: ACE inhibitors (e.g., enalapril, lisinopril) – particularly effective in renovascular hypertension.
- Second-line: calcium channel blockers (amlodipine) or beta-blockers (atenolol) – may be added for BP control.
- Target BP: < 90th percentile for age, sex, and height (or < 130/80 mm Hg in adolescents).
- Monitoring: measure four-limb BP regularly to assess disease activity.
- Interventional: renal artery angioplasty with stenting may be needed for severe stenosis (after inflammation controlled).
- Avoid: NSAIDs (may worsen renal function in renovascular hypertension).
❓ Q9. What is the EULAR/PRES criteria for Takayasu arteritis?
✅ Model Answer: • EULAR/PRES criteria (2008):
- Mandatory: Angiographic abnormality (stenosis, occlusion, aneurysm of the aorta or its major branches) – confirmed by MRA/CTA or conventional angiography.
- Plus ≥1 of the following:
1. Pulse deficit or claudication: diminished/absent pulses, or limb claudication.
2. Blood pressure difference: >10 mm Hg difference between arms.
3. Bruits: vascular bruit over aorta or its major branches.
4. Hypertension: >95th percentile for age and sex.
5. Elevated acute phase reactants: ESR > 20 mm/hr or CRP > 10 mg/L.
- Note: diagnosis is clinical + imaging; biopsy is rarely performed.
❓ Q10. What is the long-term prognosis for a child with Takayasu arteritis?
✅ Model Answer: • Prognosis:
- 5-year survival: 80-90% with modern therapy.
- Relapse rate: 50-70% – relapses are common, especially during steroid tapering.
- Treatment response: most patients respond to glucocorticoids; biologics improve outcomes in refractory cases.
- Chronic complications: hypertension, aortic regurgitation, aneurysm, stroke, and renal failure.
- Quality of life: may be affected by chronic disease, medication side effects, and fatigue.
- Regular follow-up: lifelong monitoring with imaging (MRA/CTA) and inflammatory markers to detect relapses and complications early.
- Transition to adult care: essential for continuity of care in adolescence.
⚡ Quick FCPS‑style MCQ
A 12-year-old girl with hypertension, a 25 mm Hg blood pressure difference between arms, a weak left radial pulse, and a carotid bruit. The most likely diagnosis is:
A. Coarctation of aortaB. Takayasu arteritisC. Fibromuscular dysplasiaD. Kawasaki disease
⚠️ Key concept:Takayasu arteritis is a large vessel vasculitis involving the aorta and its major branches. Hypertension with blood pressure asymmetry (>10 mm Hg) and absent/diminished pulses are hallmark features. Constitutional symptoms (fever, weight loss) often precede vascular signs. Diagnosis is confirmed by MRA or CTA showing vessel wall thickening, stenosis, or aneurysm. Treatment is glucocorticoids plus tocilizumab or TNF inhibitors for refractory/steroid-dependent disease.
• Pathophysiology: Chronic granulomatous panarteritis of aorta and its major branches; leads to stenosis, occlusion, or aneurysm; female predominance (2-4:1)