Systemic Vasculitis

Question 1

What is vasculitis?

Answer 1

Rare disease where there is inflammation of the blood vessels

Question 2

Pathophysiology of vasculitis?

Answer 2

primary - idiopathic autoimmune process
secondary - drugs, infection or other autoimmune (RA)

1. Activation of immune cells infiltrate into vessel wall and leads to direct damage and stimulates vascular smooth muscle cell remodelling
2. Vessel wall infiltration, proliferation and damage causes weakening and occlusion of blood vessel
3. Leads to ischaemia, infarction and aneurysm
4. Results in clinical manifestations

Question 3

How are vasculitides categorised?
Name 1 large vessel, 1 ANCA associated small vessel, 1 medium vessel and 1 immune complex mediated small vessel vasculitis

Answer 3

They are classified based on the vessel size affected and common features.

Large

• Giant cell arteritis
• Takayasu arteritis

ANCA associate small vessel

• Granulomatosis with polyangitis
• Microscopic polyangitis
• Eosinophilic granulomatosis with polyangitis

Medium vessel

• Kawasaki disease
• Polyarteritis nodosa

Immune complex mediated small vessel
- IgA vasculitis

Question 4

What is giant cell arteritis?
Peak age of presentation?
What are the 2 clinical presentations of GCA?

Answer 4

Commonest vasculitis
Peak age = 70-80yrs and rare below 50
- Cranial GCA
- Large vessel GCA

Question 5

Complications of GCA? Biggest complication fear?

Answer 5

• medical emergency
• may cause strokes (1%) if untreated and blindness (20%) if affecting opthalmic artery
• visual outcomes are poor and failure to regain visual fields is common (bilateral simultaneous visual loss)

Question 6

Clinical features of cranial GCA?

Answer 6

• new localised headache (abrupt and temporal)
• temporal artery thickening which is visible
• visual symptoms (blurring, amaurosis fugax, diplopia, photopsia, visual loss)
• scalp tenderness eg. when brushing hair
• jaw and tongue claudication

Question 7

Clinical features of large vessel GCA

Answer 7

Polymyalgia
Constitutional symptoms (fever & malaise)
Limb claudication

Question 8

Features which suggest a serious headache but rule out GCA?

Answer 8

vomiting - not a sign of GCA (raised ICP)

fever (infection)

Question 9

Investigation for GCA?

Answer 9

Systemic inflammation on bloods
Anaemia of chronic disease
Thrombocytosis
Raised CRP and ESR
Temporal artery ultrasound - must be done quickly
Temporal artery biopsy
PET-CT and axillary US may be used to investigate for extra-cranial disease

Question 10

Management of GCA

Answer 10

• no delay in corticosteroids - prednisolone
• taper pred over 12 m
• methotrexate can be considered in those with high risk of toxicity

Question 11

What condition do we need to exclude when we get an elderly patient presenting with new, persistent headache & how do we manage?

Answer 11

GCA - prednisolone.

Question 12

Pathogenesis of GCA?

Answer 12

• Initial inflammatory event:activation of innate and adaptive immune responses leads to local vessel inflammation and recruitment of macrophages into the vessel wall.
• Vessel wall damage: infiltration of immune cells and release of cytokines leads to damage of the vessel wall. In particular, damage to the internal elastic lamina.
• Growth and angiogenic factors:tissue injury leads to release of growth and angiogenic factors that promote new blood vessel formation, proliferation of myofibroblasts and marked thickening of the internal vessel layer (i.e. tunica intima).
• Narrowing and ischaemia:hyperplasia and expansion of the intimal layer leads to vessel narrowing and subsequent ischaemia to the area supplied by the artery. This causes the characteristic features of GCA.