Takayasu arteritis

01OverviewDefinition, clinical context and the essential points that orientate the chapter.

Takayasu arteritis is granulomatous large-vessel vasculitis affecting the aorta, its major branches and sometimes pulmonary and coronary arteries. Early disease may cause fever, fatigue, weight loss, myalgia and raised markers before vascular findings appear. Later stenosis produces arm or leg claudication, pulse loss, bruits, pressure differences, dizziness, visual symptoms, hypertension and organ ischaemia. Aortic-root disease causes regurgitation and aneurysm.

Diagnosis depends on vascular phenotype and imaging rather than one antibody. MRA avoids radiation and shows wall and lumen; CTA provides high-resolution anatomy and calcification; ultrasound is useful for carotid and subclavian wall; FDG-PET detects metabolic activity but also atherosclerosis. Image the whole aorta and branches because symptoms underrepresent distribution. Catheter angiography is reserved mainly for intervention because it maps lumen but not wall inflammation.

Activity assessment combines new symptoms, examination, markers and serial imaging. Fixed stenosis can cause symptoms without current inflammation; collateral formation can hide severe damage. Conversely, inflammation can persist with normal CRP. Tocilizumab directly suppresses CRP. The treatment question must be stated: is this active wall inflammation needing immune escalation, fixed anatomy needing revascularisation, or both?

Glucocorticoid begins active-disease treatment, with methotrexate, azathioprine, leflunomide or mycophenolate introduced early. TNF inhibitors or tocilizumab are specialist options for refractory disease. Pressure, lipids, smoking and antiplatelet decisions are individual; antiplatelet is not automatic for every patient. Pregnancy is planned during remission with compatible therapy, reliable pressure measurement and aortic, renal and cardiac risk assessment.

Key points

Suspect Takayasu arteritis in a person usually younger than fifty with unexplained inflammation, limb claudication, bruits, absent pulses, inter-arm pressure difference, renovascular hypertension or cerebral symptoms.
Measure blood pressure in both arms and, when upper-limb disease makes values unreliable, use an unaffected limb or validated lower-limb strategy with vascular advice.
Examine carotid, subclavian, aortic, renal and limb territories, heart murmurs and end-organ perfusion; normal peripheral oxygen saturation does not assess arterial supply.
Use MRA or CTA of the entire aorta and major branches for diagnosis and anatomical mapping; ultrasound helps accessible arteries and FDG-PET can support activity assessment.
Inflammatory markers support but neither prove nor exclude active disease, particularly during glucocorticoid or IL-6 blockade.
Obtain tissue only when surgery or another diagnosis provides a safe opportunity; large-artery biopsy is not a routine confirmatory route.
Start high-dose glucocorticoid for active disease and add a conventional steroid-sparing agent early because relapse during steroid monotherapy is common.
Use biologic therapy, commonly TNF inhibition or tocilizumab, for refractory or relapsing disease under specialist off-label and commissioning pathways.
Perform elective angioplasty or bypass when inflammation is controlled where possible because active wall disease increases restenosis and procedural complications.
Treat critical cerebral, coronary, mesenteric, renal or limb ischaemia immediately; threatened tissue overrides the preference to wait for inflammatory remission.

02AetiologyUnderlying causes, associations and risk factors, with why each one matters.

Polygenic immune susceptibility

HLA-B52 and other immune-regulatory variants increase susceptibility, with geographical and ancestry patterns suggesting interacting genetic and environmental influences.

Granulomatous autoimmune arteritis

No single infection is established; immune activation targets the aorta and major branches in a disease more common among younger women.

Delayed recognition

Early systemic symptoms are nonspecific and vascular collaterals can mask stenosis, allowing diagnosis only after pulse, pressure or organ-ischaemic damage appears.

03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.

1
Arterial-wall granulomatous inflammation
T cells and macrophages infiltrate adventitia and media of the aorta and proximal branches, causing oedema, mural thickening and elastic destruction.
2
Fibrotic luminal stenosis
Healing and intimal proliferation narrow or occlude vessels, producing pulse deficits, bruits, pressure asymmetry and organ hypoperfusion.
3
Wall weakening and dilation
Destruction can also cause aneurysm, aortic-root enlargement and regurgitation, so stenotic and dilating lesions may coexist.
4
Activity-damage dissociation
Inflammation may quiet while fixed stenoses remain symptomatic, and markers may normalise despite wall activity, making treatment and intervention decisions difficult.

04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.

Pre-pulseless inflammatory phase

Unexplained fever, fatigue, myalgia and high markers in a young person can precede vascular signs but requires broad infection and malignancy assessment.

Upper-limb arterial disease

Arm claudication, weak radial pulse, supraclavicular bruit and inter-arm pressure difference indicates subclavian or brachiocephalic stenosis.

Cerebrovascular diseaseRed flag

Dizziness, syncope, retinal symptoms, TIA or stroke with carotid or vertebral bruits indicates threatened cerebral flow.

Renovascular hypertension

Severe or resistant hypertension with renal-artery narrowing can be the first presentation and requires reliable limb-pressure interpretation.

Aortic and coronary diseaseRed flag

Chest pain, heart failure, aortic regurgitation or unequal pulses may indicate coronary ostial, root, aneurysmal or dissecting disease.

Red flags requiring action

Focal neurological deficit, transient retinal loss or cerebral hypoperfusion symptoms require emergency stroke and vascular imaging.
Chest pain, troponin rise, new heart failure or aortic regurgitant murmur suggests coronary ostial or aortic-root disease.
Severe abdominal pain or lactate rise may reflect mesenteric ischaemia and needs urgent surgical review.
Marked inter-arm pressure difference, absent pulses or limb rest pain indicates critical stenosis rather than constitutional inflammation alone.
Pregnancy with uncontrolled renovascular hypertension, aortic disease or active inflammation requires high-risk maternal cardiovascular care.

05InvestigationsWhat to request, why it matters and how to interpret it.

Investigation order

Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.

01
Four-limb vascular examinationFirst step
Why
Map pulse, pressure, bruit and perfusion abnormalities and establish a clinical baseline.
Interpretation and limitations
A low pressure in a stenosed arm can conceal systemic hypertension; document the limb and technique used for monitoring.
02
MRA of aorta and branches
Why
Define mural thickening, enhancement, stenosis, occlusion and aneurysm without ionising radiation.
Interpretation and limitations
Preferred repeated cross-sectional modality when available, but gadolinium, artefact and access matter; wall enhancement is not perfectly specific for activity.
03
CTA of aorta and branches
Why
Provide rapid high-resolution wall and lumen anatomy for emergency and procedural planning.
Interpretation and limitations
CTA shows stenosis, aneurysm, calcification and complications but uses radiation and iodinated contrast and cannot alone determine immune activity.
04
FDG-PET CT
Why
Support assessment of metabolically active large-vessel inflammation when clinical and structural findings disagree.
Interpretation and limitations
Glucocorticoid rapidly reduces uptake and atherosclerosis causes signal; interpret pattern and intensity with expert radiology.
05
CRP, ESR, FBC, renal, urine and cardiac tests
Why
Measure systemic inflammation, organ consequences and treatment baseline.
Interpretation and limitations
Normal markers do not exclude activity; creatinine may stay normal in unilateral renal stenosis and troponin or echo is symptom-directed.
06
Catheter angiography
Why
Resolve anatomy and enable angioplasty or stenting when intervention is planned.
Interpretation and limitations
It is the luminal procedural reference but does not show the entire arterial wall and is not routine screening.

06Differential diagnosisRealistic alternatives and the features that help distinguish them.

Atherosclerosis and thrombosis

Premature atherosclerosis, embolus and thrombophilia cause occlusion without the typical long-segment wall inflammation and systemic inflammatory history.

Fibromuscular dysplasia

Renal and cervical medium-artery beading in young women can cause hypertension or dissection but lacks aortic wall inflammation and constitutional phase.

Coarctation and congenital disease

Congenital aortic narrowing and arch anomalies produce pressure and pulse differences from birth or childhood without inflammatory wall change.

Other aortitis

GCA, IgG4 disease, syphilis, tuberculosis, Behcet disease and inflammatory bowel or spondyloarthritis-associated aortitis require age, anatomy, infection and systemic context.

07ManagementImmediate care, first-line treatment, alternatives and escalation.

01First-line imagingMap the entire arterial treeFirst stepFirst lineA young person has inflammatory symptoms with pulse, pressure, bruit or organ-ischaemic findings.

1Perform four-limb pressures, pulses, bruits, cardiac and neurological examination and obtain inflammation, renal and organ baseline tests.
2Request MRA or CTA from aortic root through major branches and add ultrasound, PET or coronary and pulmonary imaging for the phenotype.
3Discuss imaging in a large-vessel vasculitis service and record active wall features, fixed damage and immediately threatened territory separately.

02Active disease treatmentStart steroid and add sparing therapyNew arterial-wall inflammation or progressive lesions indicate active Takayasu disease without immediate procedural emergency.

1Start prednisolone 0.5–1 mg/kg/day and introduce methotrexate or another conventional steroid-sparing agent early.
2Taper against symptoms, examination, markers and repeat imaging, while preventing fracture, infection and metabolic toxicity.
3For persistent or relapsing activity use a TNF inhibitor or tocilizumab through expert off-label pathways, recognising CRP suppression with IL-6 blockade.

03RevascularisationIntervene on critical fixed anatomySevere stenosis or aneurysm causes organ ischaemia, refractory hypertension or rupture risk.

1Determine whether symptoms arise from active inflammation, fixed anatomy or both and involve vascular, cardiac, renal or neurointerventional specialists.
2Perform elective angioplasty or bypass after inflammation is controlled where feasible; intervene immediately when tissue or life is threatened.
3Continue immune control and monitor graft, stent, restenosis and anastomotic aneurysm with the agreed imaging schedule.

04Pregnancy planningEnter pregnancy in vascular remissionPregnancy is planned in a patient with current or previous Takayasu arteritis.

1Assess aorta, heart, renal arteries, cerebral flow and reliable pressure site and achieve stable disease on compatible therapy.
2Replace methotrexate, mycophenolate and renin-angiotensin blockers before conception and coordinate aspirin only for an obstetric or vascular indication.
3Use maternal cardiovascular and fetal-growth surveillance and an anaesthetic delivery plan matched to stenosis, aneurysm and hypertension.

Key medicines and prescribing safety4 treatments · regimens, roles and cautions

Rapid suppression of arterial-wall inflammation during initial or relapsing active disease.

Prednisolone

For active Takayasu arteritis use 0.5–1 mg/kg orally once daily, commonly up to 60 mg/day, then taper after clinical and imaging response with early steroid-sparing therapy.

Exclude infection, monitor glucose, pressure using a reliable limb, mood, eyes and bone and provide prophylaxis according to total immune risk. Never stop prolonged therapy abruptly.

Common off-label early conventional steroid-sparing treatment for active large-vessel inflammation.

Methotrexate with folic acid

Give 7.5–15 mg by mouth or subcutaneous injection on one day each week; prescribe folic acid at least 5 mg on a separate day. Increase if needed, commonly to 20–25 mg weekly.

Write the weekday clearly and never permit daily dosing. Monitor full blood count, transaminases and renal function; pause for serious infection and do not combine with trimethoprim or co-trimoxazole. Maternal treatment stops at least one month before conception.

TNF inhibition for relapsing or refractory active disease despite glucocorticoid and conventional treatment.

Adalimumab

A common off-label specialist regimen for refractory Takayasu arteritis is 40 mg subcutaneously every other week, adjusted only through the biologic service.

Screen TB, hepatitis and infection, update vaccination and monitor serious infection, demyelination, heart failure and paradoxical inflammation. It may continue in pregnancy when needed; if low flare risk it can stop by 28 weeks for normal infant vaccination, whereas third-trimester exposure requires deferring infant live vaccines until six months.

IL-6 receptor blockade for selected refractory disease and steroid reduction.

Tocilizumab

A common off-label regimen is 162 mg subcutaneously once weekly under specialist large-vessel-vasculitis care.

Screen infection, TB and hepatitis and monitor neutrophils, platelets, liver and lipids; CRP and fever may be suppressed, and diverticulitis increases perforation concern. Pregnancy use is reserved for severe disease when compatible alternatives are unsuitable, with infant live-vaccine advice after third-trimester exposure.

08ComplicationsImportant consequences, why they occur and why they matter clinically.

Cerebral, retinal and limb ischaemia

Carotid, vertebral and subclavian stenosis causes TIA, stroke, visual loss, syncope, claudication, tissue loss and permanent functional disability.

Renovascular and cardiac disease

Renal-artery stenosis drives severe hypertension, while coronary ostial disease, myocarditis, aortic regurgitation and heart failure threaten survival.

Aneurysm and dissection

Inflamed and weakened aortic segments can progressively dilate, rupture or dissect, particularly when systemic blood pressure remains uncontrolled.

Treatment and procedural failure

Infection and steroid toxicity coexist with restenosis, graft failure and anastomotic aneurysm when intervention occurs during active inflammation.

09Monitoring and follow-upTreatment response, safety checks and longer-term review.

At each visit repeat pressures in documented reliable limbs, pulses, bruits, claudication, neurological, visual, cardiac, abdominal and limb symptoms.
Trend CRP and ESR but never use them alone, particularly during tocilizumab; compare with examination and imaging.
Repeat MRA or CTA after treatment initiation and thereafter at a disease- and lesion-specific interval, minimising radiation when possible.
Monitor renal function, hypertension, lipids, smoking and end-organ consequences and inspect any graft or stent territory.
Apply medicine-specific FBC, liver, infection, TB, hepatitis, immunoglobulin and reproductive safety.
Before pregnancy and procedures update aortic, coronary, cerebral and renal anatomy and identify the safest pressure and vascular-access sites.

10Special situationsVariants, exceptions and circumstances that change the usual approach.

Low arm pressure can hide hypertension

Subclavian stenosis may make the usual cuff reading falsely reassuring while central or lower-limb pressure remains dangerous.

Angiography shows lumen, not activity

A tight stenosis may be old scar and a mildly narrowed artery may have active wall inflammation; cross-sectional wall imaging adds context.

Collaterals delay symptoms

Slow occlusion can permit alternative flow, so a quiet limb does not mean anatomy is mild.

CRP can lie twice

Active disease can occur with normal markers, and tocilizumab pharmacologically suppresses CRP during both relapse and infection.

Timing changes procedural durability

Restenosis and complications are more frequent when elective intervention crosses actively inflamed arterial tissue.

11Common pitfallsFrequent interpretation and management errors.

01
Measuring blood pressure in only one stenosed arm and missing severe systemic hypertension.
02
Imaging only the symptomatic limb rather than the whole aorta and major branches.
03
Equating a normal CRP with remission or a fixed stenosis with active inflammation.
04
Starting repeated steroid courses without a conventional steroid-sparing agent.
05
Delaying emergency revascularisation of threatened brain, bowel, heart or limb solely to suppress inflammation first.
06
Planning pregnancy without current aortic, renal, cardiac and pressure-site assessment.