Introduction
Takayasu's arteritis is a large vessel vasculitis. It typically causes occlusion of the aorta and questions commonly refer to an absent limb pulse. It is more common in females and Asian people
Epidemiology
- Incidence: 0.26 cases per 100,000 person-years
- Peak incidence: 20-30 years
- Sex ratio: more common in females 7:1
| Condition | Relative incidence |
|---|---|
| Temporal arteritis | 76.92 |
| Behcet's syndrome | 3.85 |
| Kawasaki disease | 3.85 |
| Takayasu's arteritis | 1 |
| <1 | 1-5 | 6+ | 16+ | 30+ | 40+ | 50+ | 60+ | 70+ | 80+ |
Aetiology
Takayasu's arteritis is of unknown aetiology. However, there are a number of studies which suggest there may be a genetic link. Certain polymorphisms of the following genes have been implicated:
The condition is most likely to affect young women.
The incidence is higher in Asian countries including Japan, Korea, China, India, Thailand, and Singapore. It is also more likely in patients of Asian descent.
- IL-12, IL-6 and IL-2.
- HLA-Bw5 and HLA-B39.2.
The condition is most likely to affect young women.
The incidence is higher in Asian countries including Japan, Korea, China, India, Thailand, and Singapore. It is also more likely in patients of Asian descent.
Clinical features
Features
- systemic features of a vasculitis e.g. malaise, headache
- unequal blood pressure in the upper limbs
- carotid bruit
- intermittent claudication
- aortic regurgitation (around 20%)
Investigations
According to the European League Against Rheumatism (EULAR) guidelines (updated in 2018), diagnosis should be confirmed with biopsy and histology or imaging.
Laboratory tests:
Imaging studies:
Laboratory tests:
- Inflammatory markers:
- Both ESR and CRP are likely to be raised.
- The sensitivity of CRP is better than ESR but both tests have poor specificity.
Imaging studies:
- Computerised tomography angiography (CTA):
- The investigation of choice, with high sensitivity and specificity. Magnetic resonance angiography (MRA) may also be used, depending on availability and local guidelines.
- Catheter angiogram:
- The traditional method of angiography which has been largely superseded by CT and MR angiography in most centres.
- Ultrasound (+/- doppler enhancement):
- This is more readily available than other imaging methods and is preferred in early or mild disease and children.
Differential diagnosis
Other vasculitic disorders may present with similar 'vascular' symptoms such as claudication, syncope and hypertension:
Infection:
- Giant cell arteritis:
- More likely to affect older patients and have temporal artery involvement. CT/MRI imaging will differentiate the diagnoses.
- Behcet's disease:
- More likely to present with arthritis, ulcers and uveitis. Angiography and lumbar puncture (raised protein) will differentiate the diagnoses.
- Kawasaki disease:
- More likely to affect young children. Presents with strawberry-tongue, lymphadenopathy and high grade fever. Echocardiogram is the investigation of choice.
- IgG4-related disease:
- A rare chronic inflammatory disease which can affect almost any organ including the heart and aorta. It is most common in middle-aged and older men.
Infection:
- Syphilis:
- May present with vasculitis of ascending aorta in tertiary disease. Firm painless chancre should be present and serology positive.
- Tuberculosis (TB):
- Both can present with haemoptysis and pleuritis. Chest X-ray and QuantiFERON® gold test are diagnostic.
Management
According to the EULAR guideline (updated in 2018) the treatment of Takayasu's arteritis should involve treatment with corticosteroids to induce remission in all patients as well as an immunosuppressive agent for a select group of patients.
Corticosteroids:
Immunosuppressive agents:
Additional considerations:
Corticosteroids:
- Oral prednisolone (1mg/kg/day) is usually first line.
- Length of treatment is dependent on factors including severity of disease and comorbidities.
- Glucocorticoids must be tapered to reduce the risk withdrawal effects.
- Steroids should be given alongside low dose aspirin (75mg daily).
Immunosuppressive agents:
- Considered 2nd line and are utilised when patients relapse during steroid tapering.
- Options include:
- Methotrexate (given with folic acid).
- Azathioprine.
- Mycophenolate mofetil.
- Cyclophosphamide.
Additional considerations:
- Bone protection is required due to the long-term use of steroids.
- Alendronic acid with calcitriol and calcium carbonate should be used.
- Patients on high dose prednisolone may require pneumocystis pneumonia prophylaxis with trimethoprim.
- If both steroids and immunosuppressive treatments are ineffective, a tumour necrosis factor (TNF)-alpha inhibitor (such as infliximab) may be started.
- Surgical intervention is indicated in patients with severe limb claudication or organ dysfunction.
- Options include percutaneous angioplasty and vascular bypass surgery.
Complications
Common:
Less common:
- Hypertension: a long term complication which may result either from renal artery stenosis (causing activation of the renin-angiotensin-aldosterone system), or aortic stenosis (increasing systemic vascular resistance), or both.
- Hypertension should be aggressively treated with antihypertensive medications.
- Peripheral vascular ischaemia: stenosis and occlusions of arteries are common. These should be investigated regularly with vascular imaging studies.
Less common:
- Aortic aneurysm or regurgitation: structural abnormality to the aortic root and thoracic aorta may occur.
- Angina and congestive heart failure: occurring in about 25% of patients
- Cerebrovascular disease: there is a low risk of both stroke and transient ischaemic attack.