Takayasu’s syndrome - Vasculitis

Takayasu’s syndrome

Definition

A chronic inflammatory arteritis of unknown aetiology affecting the aorta and its main branches.

Incidence

1–3 per 1,000,000 per year.

Age

Commonest between 10 and 40 years.

Sex

80–90% females.

Geography

Largest number of cases in Asia and Africa.

Pathophysiology

Initially inflammation occurs in the left subclavian artery progressing to involve the carotids, vertebral, brachiocephalic, aorta and pulmonary arteries. Inflammation may cause vessel wall thickening, and narrowing, occlusion or dilation of affected vessels. T cells and antiendothelial antibodies have been implicated in the pathogenesis.

Clinical features

After an initial prodromal illness patients present with weight loss, myalgia and synovitis. On examination patients appear unwell, and the blood pressure may be reduced in one or both arms. However, hypertension often develops due to renal artery or aortic narrowing. Arterial pulses in the limbs are often asymmetrically reduced with bruits on auscultation. There may be features of arterial insufficiency with limb claudication, cool extremities and in severe cases ischaemic ulceration or gangrene.

Microscopy

Intimal proliferation with scarring of the media and loss of elastic fibres. There is lymphocytic infiltration and fibrosis.

Investigations

Inflammatory markers (ESR, CRP) are often raised and there may be anaemia of chronic disease. Although arteriography remains the gold standard for diagnosis, it may be superseded by CT or MR angiography.

Management

Corticosteroids are the mainstay of treatment, with methotrexate and azathioprine used in refractory cases. Percutaneous angioplasty or surgical bypass of affected arteries may be required in irreversible vessel stenosis with significant ischaemia.

Prognosis

Most patients survive at least 5 years.