Overview
Definition:
Takayasu arteritis is a rare, chronic, inflammatory disease affecting large arteries, primarily the aorta and its main branches
In children, it's a form of primary large vessel vasculitis leading to stenosis, occlusion, aneurysms, or dissection.
Epidemiology:
It is a rare condition in children, accounting for a small percentage of vasculitis cases
Incidence is higher in females, with a bimodal age distribution peaking in adolescence and early adulthood, but can occur at any age in childhood
Affects South Asian, East Asian, and Hispanic populations more frequently.
Clinical Significance:
Early diagnosis and aggressive management are crucial in pediatric Takayasu arteritis to prevent irreversible vascular damage, organ ischemia, severe hypertension, and long-term morbidity, impacting growth and development significantly.
Clinical Presentation
Symptoms:
Nonspecific constitutional symptoms: fever, fatigue, weight loss
Vascular symptoms: claudication (arm or leg pain with exertion), absent or diminished peripheral pulses, unequal blood pressures between limbs, headaches, visual disturbances (amaurosis fugax, retinopathy)
Hypertension, often severe, is a hallmark
Murmurs may be heard over affected arteries
Signs of organ ischemia depending on arterial involvement (e.g., renal artery stenosis leading to renal failure, mesenteric artery involvement leading to abdominal pain).
Signs:
Diminished or absent peripheral pulses
Blood pressure differential between upper extremities or between arms and legs (>10-20 mmHg systolic)
Bruits over large arteries (carotid, subclavian, abdominal aorta)
Signs of heart failure if aortic regurgitation or coronary artery involvement
Fundoscopic examination may reveal signs of hypertensive retinopathy or retinal artery occlusion.
Diagnostic Criteria:
While no specific pediatric criteria exist, the American College of Rheumatology (ACR) 1990 classification criteria for Takayasu arteritis are often adapted
Key features include age < 50 years at onset, claudication of extremities, decreased peripheral pulses, blood pressure difference >10 mmHg systolic, bruits over subclavian or aorta, and arteriographic abnormalities (luminal irregularity, stenosis, occlusion, aneurysm, or tortuosity) of the aorta, its primary branches, or the arteries of the Allahabad
At least 3 of these criteria are needed for classification.
Diagnostic Approach
History Taking:
Detailed history of constitutional symptoms, exercise intolerance, limb pain, headaches, visual changes, and prior diagnoses of hypertension or murmurs
Family history of autoimmune diseases or vasculitis
Medication history, especially related to blood pressure control
Red flags include new-onset severe hypertension in a child, unequal pulses, or limb claudication.
Physical Examination:
Systematic assessment of peripheral pulses in all four limbs (radial, brachial, femoral, dorsalis pedis, posterior tibial)
Bilateral blood pressure measurements in arms and legs
Auscultation for bruits over carotid arteries, subclavian arteries, abdominal aorta, and renal arteries
Cardiac and pulmonary auscultation for murmurs, rubs, and signs of heart failure
Fundoscopic examination
Neurological assessment for signs of cerebral ischemia.
Investigations:
Inflammatory markers: Elevated ESR and CRP are common but not specific
Complete blood count (CBC) may show anemia of chronic disease
Renal function tests (creatinine, BUN) to assess for renal artery involvement
Lipid profile
Autoimmune markers: ANA, ANCA, RF, anti-CCP usually negative
Imaging: Arteriography (conventional catheter angiography) is the gold standard but invasive
Non-invasive imaging is preferred: Doppler ultrasonography of aorta and branches, CT angiography (CTA), or MR angiography (MRA) are crucial to visualize arterial wall thickening, stenosis, occlusion, and aneurysms
Chest X-ray to assess aortic size and calcification
Echocardiography to assess for valvular involvement and cardiac function
Echocardiography can also assess aortic root and ascending aorta.
Differential Diagnosis:
Other vasculitides (e.g., Kawasaki disease, polyarteritis nodosa, ANCA-associated vasculitis), fibromuscular dysplasia, atherosclerotic disease (rare in children), congenital anomalies of the aorta, aortitis secondary to infection (e.g., syphilis) or other inflammatory conditions (e.g., juvenile idiopathic arthritis, systemic lupus erythematosus).
Management
Initial Management:
Goal is to induce remission, prevent further vascular damage, and control inflammation
Initial treatment usually involves high-dose corticosteroids
Aggressive blood pressure control is paramount, often requiring multiple antihypertensive agents
Early consultation with pediatric rheumatologists and cardiologists is essential.
Medical Management:
Corticosteroids: Prednisolone 1 mg/kg/day (max 60 mg/day) orally or IV, then tapered over months to lowest effective dose
Immunosuppressive agents: Methotrexate is often the first-line steroid-sparing agent, given at 10-15 mg/m²/week
Azathioprine, leflunomide, or cyclophosphamide may be used for refractory disease or severe manifestations
Biologics: TNF-alpha inhibitors (e.g., etanercept, infliximab, adalimumab) and IL-6 inhibitors (e.g., tocilizumab) are increasingly used as steroid-sparing agents or for refractory disease
Specific doses and protocols vary and are guided by expert consensus and clinical response
Antihypertensive therapy: ACE inhibitors (e.g., enalapril), ARBs (e.g., losartan), calcium channel blockers, or diuretics are used to manage hypertension
Beta-blockers may be used cautiously
Revascularization therapy: Antiplatelet agents (e.g., aspirin) are often used, especially if there is evidence of luminal irregularity or thrombus formation.
Surgical Management:
Surgical intervention is reserved for complications like severe arterial stenosis/occlusion not amenable to medical management, aneurysms, or dissections, or significant residual stenosis despite medical therapy
Procedures may include angioplasty with stenting, bypass grafts (e.g., aortofemoral bypass, carotid subclavian bypass), or aneurysm repair
This is often managed by vascular surgeons in conjunction with rheumatologists.
Supportive Care:
Nutritional support to address weight loss or failure to thrive
Psychological support for the child and family due to the chronic nature of the illness
Regular monitoring of growth and development
Rehabilitation services may be beneficial for patients with significant limb claudication or functional limitations.
Complications
Early Complications:
Malignant hypertension, hypertensive encephalopathy, stroke, myocardial infarction (rare in children), aortic dissection, acute limb ischemia, renal failure due to renal artery stenosis, visual loss.
Late Complications:
Chronic hypertension, progressive vascular stenosis leading to irreversible organ damage, aneurysm formation, aortic regurgitation, coronary artery disease, chronic renal insufficiency or failure, infertility in females due to involvement of pelvic arteries.
Prevention Strategies:
Aggressive and early control of inflammation with immunosuppressive therapy
Strict blood pressure monitoring and management
Regular vascular imaging to detect and manage stenotic lesions before they cause significant ischemia
Patient education on recognizing symptoms of worsening disease or complications.
Prognosis
Factors Affecting Prognosis:
Severity of initial disease, extent of vascular involvement, presence and severity of hypertension, response to initial treatment, adherence to therapy, and development of complications
Early diagnosis and aggressive management significantly improve outcomes.
Outcomes:
With modern immunosuppressive and biologic therapies, remission can be achieved in a significant proportion of patients, leading to reduced vascular damage and improved long-term outcomes
However, some patients may experience relapsing disease or develop chronic sequelae requiring lifelong management.
Follow Up:
Long-term, regular follow-up is essential
This includes clinical assessment for symptoms, monitoring blood pressure, regular inflammatory markers, and serial vascular imaging (ultrasound, CTA, or MRA) to assess disease activity, detect new lesions, and monitor existing ones
Annual echocardiography may be warranted
Patients often require lifelong monitoring and management.
Key Points
Exam Focus:
Takayasu arteritis in children is a large vessel vasculitis primarily affecting the aorta and its branches
Key manifestations include hypertension, absent pulses, bruits, and limb claudication
Imaging (MRA, CTA) is crucial for diagnosis
Management involves steroids, immunosuppressants, and increasingly biologics (TNF inhibitors, IL-6 inhibitors)
DNB/NEET SS questions often focus on diagnostic imaging, management protocols, and complications.
Clinical Pearls:
Always check bilateral blood pressures in children presenting with hypertension or murmurs
Consider Takayasu arteritis in a child with unexplained severe hypertension and absent pulses
MRA is often the preferred initial non-invasive imaging modality
Aggressive BP control is as critical as anti-inflammatory therapy
Monitor for silent ischemia in mesenteric and coronary arteries.
Common Mistakes:
Underestimating the severity of hypertension
Delaying aggressive immunosuppressive therapy
Misinterpreting imaging findings without clinical correlation
Inadequate follow-up leading to progression of vascular damage
Failing to consider other causes of vasculitis or hypertension in the differential diagnosis.