Takayasu arteritis

Definition

Takayasu arteritis is an inflammatory disease of the aorta, its main branches, and the pulmonary arteries. It is a large-vessel vasculitis and mainly affects young women. Vascular inflammation may cause stenosis, occlusion, dilation, or aneurysms.

Occurrence & epidemiology

The disease is rare and most common in Asia but occurs worldwide. The female-to-male ratio is 8:1; onset is typically between 15 and 30 years of age. In North America, the annual incidence is estimated at 2.6 per million.

Aetiopathogenesis

The cause is unknown; cell-mediated immune mechanisms are suspected. Most commonly affected are the innominate and subclavian arteries, ascending aorta and aortic arch, common carotid arteries, and renal arteries. Most patients have stenoses or occlusions; aneurysms occur in about one-third, and the pulmonary arteries are involved in half. Because of the chronic course, collateral circulation develops, so gangrene is rare.

Clinical features

• Constitutional symptoms in about 50 %: fever, malaise, night sweats, weight loss, fatigue, arthralgias.
• Extremities: pain and fatigue with arm use (claudication), absent, diminished, or asymmetric pulses ("pulseless disease"), blood pressure difference between the arms, cool extremities; bruits over the subclavian, carotid, abdominal aortic, or femoral arteries.
• Cerebral: dizziness, syncope, headache, transient visual disturbances, transient ischemic attacks, strokes; subclavian steal syndrome.
• Heart: angina or myocardial infarction from involvement of the coronary ostia, aortic regurgitation with a dilated ascending aorta, heart failure.
• Hypertension, including renovascular or due to coarctation-like stenosis of the descending aorta.
• Pulmonary hypertension and pulmonary infarcts with pulmonary artery involvement.

Histology

Early changes consist of adventitial mononuclear infiltrates with perivascular cuffing of the vasa vasorum, later intense inflammation of the media, sometimes with granulomas, giant cells, and patchy necrosis. The picture may be indistinguishable from giant cell arteritis.

Diagnosis

• Suspicion with signs of ischemia in organs supplied by the aorta or diminished pulses in young people, especially women, without atherosclerotic risk; bruits and side-to-side differences in pulse and blood pressure.
• Blood pressure measurement in all extremities; with bilateral subclavian involvement, systemic pressure can be measured reliably only in the legs.
• MR angiography or CT angiography of all aortic branches: stenosis, occlusion, wall irregularities, poststenotic dilation, collaterals, and aneurysms; MR angiography requires neither radiation exposure nor iodinated contrast.
• FDG-PET may show inflamed vessel segments; conventional angiography depicts the lumen.
• Laboratory tests nonspecific: anemia of chronic disease, thrombocytosis, elevated ESR and CRP; inflammatory markers may be normal despite active arteritis.

Keep learning in the app

Further reading (open access)

1. MSD Manual Professional: Takayasu Arteritis
2. MSD Manual Professional: Overview of Vasculitis

Cross-references