Vasculitis

Question 1

What is the core concept of vasculitis?

Answer 1

Autoimmune inflammation of blood vessel walls causing fibrinoid necrosis → ischaemia and organ injury.

Question 2

How are vasculitides grouped by vessel size?

Answer 2

Large (GCA, Takayasu), Medium (PAN), Small (AAV: GPA, MPA, EGPA ± immune-complex like IgA, Cryo, CTD, Drug).

Question 3

What is the mechanism of ANCA-associated vasculitis?

Answer 3

Neutrophil activation via PR3 or MPO → ROS release → necrotising vasculitis.

Question 4

What are the key immune-complex vasculitis triggers?

Answer 4

HBV, HCV, drugs (PTU, hydralazine), SLE, RA, Sjögren’s.

Question 5

What are the hallmark biopsy findings in small-vessel vasculitis?

Answer 5

Fibrinoid necrosis with leukocytoclasis.

Question 6

What are hallmark biopsy findings in large-vessel vasculitis?

Answer 6

Granulomatous arteritis with internal elastic lamina (IEL) disruption.

Question 7

What is Giant Cell Arteritis (GCA)?

Answer 7

Granulomatous large-vessel vasculitis in >50 y females, often with PMR overlap.

Question 8

What are key features of GCA?

Answer 8

Temporal headache, scalp tenderness, jaw claudication, visual loss, high ESR/CRP.

Question 9

What is seen on GCA biopsy?

Answer 9

Granulomatous arteritis with giant cells and IEL fragmentation.

Question 10

What imaging is used for GCA?

Answer 10

US (halo sign), PET/MRA for aortitis.

Question 11

How is GCA treated?

Answer 11

Pred + Tocilizumab for 6-month taper (GiACTA 2017); IVMP for visual risk.

Question 12

What is Takayasu arteritis?

Answer 12

Granulomatous aortitis in <40 y Asian women causing pulse loss and BP asymmetry.

Question 13

What is diagnostic imaging for Takayasu?

Answer 13

CTA/MRA/PET showing aortic wall thickening or stenosis.

Question 14

How is Takayasu treated?

Answer 14

Pred ± MTX/AZA; refractory → Tocilizumab or TNFi.

Question 15

What is Polyarteritis Nodosa (PAN)?

Answer 15

Necrotising arteritis of medium arteries sparing lungs; linked to HBV.

Question 16

What are key features of PAN?

Answer 16

Fever, neuropathy, livedo reticularis, renal infarcts, hypertension.

Question 17

What is the hallmark angiographic finding in PAN?

Answer 17

Microaneurysms (‘string of beads’).

Question 18

How is PAN treated?

Answer 18

Pred + CYC; HBV PAN → antivirals + short Pred + plasmapheresis.

Question 19

What is Granulomatosis with Polyangiitis (GPA)?

Answer 19

PR3/c-ANCA-positive necrotising granulomatous vasculitis affecting ENT, lungs, kidneys.

Question 20

What are key GPA features?

Answer 20

Sinusitis, saddle-nose, nodules, haematuria (RBC casts).

Question 21

How is GPA treated?

Answer 21

Pred + Rituximab (or CYC); add Avacopan for steroid-sparing.

Question 22

What is Microscopic Polyangiitis (MPA)?

Answer 22

MPO/p-ANCA-positive small-vessel vasculitis with GN and alveolar haemorrhage.

Question 23

What differentiates GPA from MPA?

Answer 23

GPA has granulomas and ENT disease; MPA does not.

Question 24

What is EGPA?

Answer 24

Asthma + eosinophilia >1.5×10⁹ + neuropathy ± cardiac involvement.

Question 25

What biopsy finding supports EGPA?

Answer 25

Necrotising vasculitis with extravascular eosinophilic granulomas.

Question 26

How is EGPA treated?

Answer 26

Pred ± CYC/RTX; add Mepolizumab or Benralizumab (IL-5 blockers).

Question 27

What is IgA vasculitis (HSP)?

Answer 27

Small-vessel vasculitis post-URTI → purpura, abdo pain, GN.

Question 28

What confirms IgA vasculitis diagnosis?

Answer 28

Skin biopsy: IgA deposition on IF.

Question 29

How is IgA vasculitis managed?

Answer 29

Supportive ± steroids for renal/GI involvement.

Question 30

What is cryoglobulinaemic vasculitis?

Answer 30

Immune-complex vasculitis from HCV → purpura, arthralgia, neuropathy, low C4.

Question 31

How is cryoglobulinaemia treated?

Answer 31

Rituximab + DAA (NEJM 2024).

Question 32

What are drug-induced vasculitis examples?

Answer 32

Hydralazine, PTU, minocycline, cocaine-levamisole, NSAIDs, allopurinol.

Question 33

What serology pattern suggests drug-induced vasculitis?

Answer 33

MPO + ANA + anti-histone positive.

Question 34

What infectious causes mimic vasculitis?

Answer 34

HBV (PAN), HCV (Cryo), HIV, endocarditis.

Question 35

What are malignancy-related vasculitis associations?

Answer 35

CLL, lymphoma, solid cancers causing LCV/Cryo-like lesions.

Question 36

What are key mimics of vasculitis?

Answer 36

FMD, cholesterol emboli, endocarditis, APS/TMA, CLL/Cryo.

Question 37

What is diagnostic clue for cholesterol emboli?

Answer 37

Blue toes + eosinophilia + AKI post-angiography.

Question 38

What are hallmark findings of FMD?

Answer 38

String-of-beads appearance, normal ESR/CRP, non-inflammatory.

Question 39

What are key investigations in suspected vasculitis?

Answer 39

ESR/CRP, ANCA, complements, urinalysis, HBV/HCV serology, biopsy.

Question 40

What is the induction regimen for ANCA vasculitis?

Answer 40

High-dose Pred + Rituximab or CYC.

Question 41

What is the maintenance regimen for ANCA vasculitis?

Answer 41

RTX q6–12m or AZA/MMF/MTX + low-dose Pred.

Question 42

What is the relapse management for AAV?

Answer 42

RTX ± Avacopan (C5a receptor blocker).

Question 43

What does PEXIVAS 2020 show?

Answer 43

No mortality/ESRD benefit; reserve for Cr>500 µmol/L or life-threatening DAH.

Question 44

What are key PBS biologics in vasculitis (Australia 2025)?

Answer 44

RTX for AAV; Tocilizumab for GCA; Mepolizumab for EGPA; Avacopan TGA only.

Question 45

What are GCA complications if untreated?

Answer 45

Irreversible blindness, aortic aneurysm, stroke.

Question 46

What is PR3 vs MPO significance?

Answer 46

PR3 → GPA, relapse-prone; MPO → MPA/EGPA, renal-heavy.

Question 47

What differentiates immune-complex vs AAV?

Answer 47

Immune-complex has low complement (C3/C4), AAV usually normal.

Question 48

What supportive measures are needed in AAV?

Answer 48

TMP-SMX PCP prophylaxis, vaccinations, infection/BP monitoring.

Question 49

What histology defines PAN?

Answer 49

Transmural necrotising arteritis with fibrinoid necrosis.

Question 50

What cytokine pathway is targeted by Tocilizumab?

Answer 50

IL-6 receptor blockade.

Question 51

What cytokine pathway is targeted by Mepolizumab?

Answer 51

IL-5 blockade (eosinophil control).

Question 52

What cytokine pathway is targeted by Avacopan?

Answer 52

C5a receptor blockade (complement inhibition).

Question 53

Which vasculitis lacks lung involvement?

Answer 53

Polyarteritis Nodosa (PAN).

Question 54

Which vasculitis spares kidneys?

Answer 54

Giant Cell Arteritis and Takayasu (large vessel).

Question 55

Which vasculitis shows skip lesions on biopsy?

Answer 55

GCA (temporal artery).

Question 56

Which vasculitis is associated with HBV?

Answer 56

PAN.

Question 57

Which vasculitis is associated with HCV?

Answer 57

Cryoglobulinaemia.

Question 58

Which vasculitis presents with asthma?

Answer 58

EGPA.

Question 59

Which vasculitis presents with ENT and lung disease?

Answer 59

GPA.

Question 60

Which vasculitis presents with neuropathy and livedo reticularis?

Answer 60

PAN.

Question 61

What is the role of aspirin in GCA?

Answer 61

Reduces risk of visual loss and stroke (if no contraindication).

Question 62

When should biopsy be done for GCA?

Answer 62

Within 1–2 weeks after steroids (yield maintained).

Question 63

What is the primary mimic of PAN?

Answer 63

Cholesterol emboli (post-angiogram, eosinophilia, AKI).

Question 64

What histological term describes leukocytoclastic vasculitis?

Answer 64

Fibrinoid necrosis with fragmented neutrophils (leukocytoclasis).

Question 65

What defines the 'Size–Site–Signature–Steroid–Saver' rule?

Answer 65

Large = GCA/Takayasu (Toci); Medium = PAN (CYC); Small = AAV (RTX ± Avacopan).

Question 66

What are exam traps in vasculitis?

Answer 66

GCA biopsy shows granuloma not fibrinoid; endocarditis can be ANCA+; always exclude infection/FMD/drug.