IMM: Vasculitis

Question 1

What is vasculitis?

Answer 1

Inflammation within blood vessel walls

can be localised or multisystem

classification: large, medium, or small vessels.

Question 2

What are the clinical features of vasculitis?

Answer 2

Rare

Varied presentation

Indolent, non-specific symptoms –> broad ddx

rare + hard to diagnose –> high morbidity and mortality

Answer 3

In general, we suspect the conditions if its multisystem, and if other causes are excluded

Gold standard test = biopsy of involved tissue; difficult in difficult areas (eg) aorta

Answer 4

Esr/crp

which organs? kidney is common so check urine (urea, electrolytes)

biopsy = gold standard (if possible)

in medium/large vessels, angiography can be useful

pet scans can be useful to show the inflammation

anca test is tailored to be diagnostic for anca associated vasculitis

Answer 5

challenges

• timely diagnosis when initial presentation is usually non-specific
• difficult to find sustain safe treatment; but becoming easier

–> mainstay of treatment = immunosuppression

Question 6

8 yo with rash + joint pain

Hx:

• 3 days of non-blanching petechiae on her legs, extending to vasculitis.
• Generalised arthralgia and joint stiffness.
• More recent abdo pain + rectal bleeding.
• Blood + protein in urine.

Answer 6

Henoch-Scholein purpura - one of the milder forms of vasculitis

common in children

Immune complex mediated

Systems/organs: kidneys, abdomen.

Size: petechial –> small vessels of the kidneys

Testing: skin biopsy

• histopathology and immunofluorescence

–> fibrinoid necrosis of small blood vessels

–> ig deposition in walls of small blood vessels (IgA predominant)

Treatment: generally self-limited, symptomatic treatment; NSAIDs for pain

Adults: chronic renal problems

Question 7

Describe the pathology of small vessel vasculitis?

Give examples?

Answer 7

[get pathology from slides]

other small vessel vasculitides

Cryoglobulinaemic vasculitis

SLE/RA

Hypocomplementaemic urticarial vasculitis (c1q antibodies, urticarial like lesions)

Question 9

pathology of cryoglobulinaemic vasculitis

what does it effect?

Answer 9

Associated with serum proteins (cryoglobulins) that precipitate in the cold and re-solubilise when heated

can also precipitate in blood vessel walls and activate complement, leading to vasculitis

Skin, peripheral nerves, kidney

associated with hep c

ix: complement low, hep c serology, detection of cryoglobulins
tx: treat underlying disease, sometimes need immunosuppresion; plasmapheresis occasionally.

Question 10

36 yo woman

Hx: 3 weeks of flu-like illness

• Anorexia
• Haemoptysis
• Sino-nasal pain and epistaxis
• Right foot drop
• Blood and protein in urine

necrotising scleritis of the eye

Answer 10

Diagnosis: Necrotising, crescentic glomerulonephritis

Small/medium/large: small to medium

tests: Biopsy the nerves, antineutrophil cytoplasmic antibody (ANCA) test, renal biopsy.

immunofluorescence negative –> “pauci-immune” –> characteristic of anca associated vasculitis

Systems/organs: upper resp (sinus pain and epistaxis), nerve, renal (blood and urine), lung involvement

Question 11

ANCA

Answer 11

• Antineutrophil cytoplasmic antibody.
• Looking for antibodies against the enzymes in the granules in neutrophils.
• Immunofluorescence.
• Two patterns
  
  • Cytoplasm pattern (cANCA) (spares nuclei)
  • Perinuclear pattern (pANCA) (outlines rim of nuclei)
• Can be diagnostic if present.
• Antibodies against enzymes are anti-PR-3 (cANCA) and anti-MPO (pANCA)
  
  • Anti-PR-3 = granulomatous polyangiitis
  • Anti-MPO = microscopic polyangiitis
• 3 ANCA vasculitides
  
  • WG
  • MPA
  • CSS
• VERY SPECIFIC TEST
• Tx: immunosuppression: pred, cyclo, rituximab, plasmapheresis

Question 12

76 yo man, non smoker

Hx: 2 month of fever, weight loss, anorexia, hypertension. Abdo pain after he eats. Foot drop.

Answer 12

Diagnosis: polyarteritis nodosa

Epidemiology: all ages, mean age = 45. Infant small child form = kawasaki disease

Rash: erythema nodosum; nodular, deep tissue rash

System/organs: Skin, nerves, GI. Kidney and MSK involvement common.

Blood vessels: Medium –> not the small vessels causing petechial rash. DEEPER RASH. Testicular involvement in men.

Diagnostic tests: Skin biopsy. Take a deeper biopsy to see larger vessels.

Diagnostic criteria = 10 points from the slides

Other tests: Angiography (putting dye in and lighting up the blood vessels), shows vessel inflammation.

Angiography of the mesenteric arteries. Related to pain in the guy post-eating

Question 13

70 yo man

Hx: 4 months of fevers, anorexia, aching shoulder, scalp tenderness, jaw claudication (due to insufficient blood supply when eating), intense headache, sudden blindness

Temporal arteries enlarged and tender

Answer 13

Diagnosis: Giant cell arteritis (GCA)/temporal arteritis

Vessels: Large

Aetiology: Dysregulation of innate and adaptive immune responses in the walls of the blood vessels.

Systems:

Tests: biopsy of temporal arteries, ESR isn’t elevated, NO WAY you can have this condition

Pathology: multinucleated giant cells; thickening of the blood vessels causing occlusion caused by inflammatory inflitrate. Intense systemic inflammation.

Panarteritis (all layers of the vessel wall are affected)

DDX: Polymyalgia rheumatica (can occur with or without GCA), Takayasu arteritis (biopsies rare, do angiography) (doesn’t generally involve temporal arteries, no jaw problems, asymmetrical pulse and BP readings). All have intense systemic inflammatory response.

(T/M)x: Steroids as soon as you can to prevent complications. Start steroids based off the high ESR, DON’T WAIT FOR BIOPSY. Steroids are long-term, tapered over 2 years.

Answer 14

rare

broad ddx, non-specific symptoms

diversity in pathogenic mechanisms

variable sx based on organs involved

blood tests can be specific eg ANCA