Large cell vasculitis (Takayasu, Giant cell)

Question 1

Large vessel vasculitis involves ______
Commonest cause (2)
Other causes

Answer 1

Aorta and its major branches

Commonest:
1. Takayasu arteritis
2. Giant cell arteritis

Others:
1. Seronegative spondyloarthropathies
2. Relapsing polychondritis
3. Behcet’s disease
4. Cogan’s syndrome
5. Sarcoidosis
6. Infectious aortitis

Question 2

Large vessel arteritis and site of involvement

Answer 2

Ascending aorta (arch, subclavian, carotids)
- GCA, TA, Behcet
- Familial thoracic arch aneurysm/dissection, Marfan, EDS

Descending aorta
- TA (Indian, Pakistan)
- Inflammatory AAA

Pulmonary artery
- Behcet

Periaorta
- IgG4 related disease
- Lymphoma
- Erdheim-Chester

Question 3

Takayasu arteritis is also known as __
It is a __ inflammation of aorta and its major branches, in which may also affect __
It results in __ and __ of large vessels

Answer 3

Pulseless disease, aortic arch syndrome, occlusive thromboaortopathy

Granulomatous inflammation
May also affect pulmonary and coronary arteries

Stenosis, aneurysm

Question 4

Epidemiology of Takayasu arteritis

Answer 4

1. Women > male (8-10:1)
2. Median age of 25 years
   (25% before 20 years; 15% after 40 years)
3. Commonly in Asians (Japan, China, India, SEA)

Question 5

Triphasic pattern of TA pathogenesis

Answer 5

Phase 1: pre-pulseless, inflammatory period
- Systemic complaints: fever, arthralgia, weight loss

Phase 2: vessel inflammation
- Vessel pain and tenderness

Phase 3 fibrosis, stenosis and aneurysm
- Bruits
- Ischaemia

Question 6

Clinical presentation of TA

Answer 6

1. Young women, asymptomatic (10%)
   - Routine discovery of unequal pulses/BP or bruit or hypertension
2. Non-specific fever, joint pain and weight loss
   (misdiagnosed as infectious syndrome)
3. Vessel pain and tenderness
   - Pain on palpation of carotid artery (carotidynia)
4. Ischaemic symptoms
   - Subclavian artery: arm claudication
   - Iliac artery: lower limb claudication
   - Carotid and vertebral artery: pre-syncope, headache
   - Pulmonary artery: pulmonary hypertension
   - Cardiac: angina, MI, heart failure, AR, sudden death
   - Renal artery: renovascular hypertension

Question 7

Investigations and diagnosis of TA

Answer 7

Lab tests
1. FBC - anaemia of chronic disease, thrombocytosis
2. Elevated ESR, CRP

Imaging
1. MR angiogram (preferred)
Alternatives: CTA, FDG-PET, ultrasound
2. Large vessel angiogram (gold standard)

Confirmatory
1. Biopsy of large vessel

Question 8

Histopathological findings of TA

Answer 8

1. Cellular infiltration around adventitia and vasa vasorum by lymphocytes (gamma or delta T lymphocytes, NK cells, CD8+ T cells) and plasma cells
2. Thickening of adventitia
3. Granuloma formation and giant cells in media
4. Intimal hyperplasia
5. Skin lesions and patchy involvement

Question 9

Is TA a genetic disease?

Answer 9

Postulated HLA Class 1 (HLA-B 52:01) but inconclusive

Question 10

ACR 1990 Criteria for TA

Answer 10

3 of the following:
1. Age onset < 40 years old
2. Limb claudication (upper or lower limbs)
3. Decreased brachial artery pulse
4. Limb BP discrepancy > 10mmHg
5. Bruit over subclavian artery or aorta
6. Arteriogram abnormalities

(Sensitivity: 74%, specificity: 98.3%)