Vasculitis Flashcards
What are the 4 vessel size classifications of vasculitis?
Small, mixed small and medium vessel, medium vessel and large vessel
What are the primary clinical features of small vessel vasculitis?
Palpable purpura, petechiae, vesicles, pustules
What are the hallmark clinical features of mixed medium and small-vessel vasculitis?
Mixture of features from small/medium vasculitis
-palpable purpura, petechiae, vesicles, pustules, livido reticularis, retiform purpura, ulcers, subcutaneous nodules
What are the hallmark clinical features of medium vessel vasculitis?
Livido reticularis, Subcutaneous nodules, retiform purpura, ulcers
What are the hallmark clinical features of large vessel vasculitis?
Specific to dz
Temporal arteritis: erythematous tender nodules or ulceration on the frontotemporal scalp
Takayasu’s arteritis: erythematous, subcutaneous nodules, PG-like lesions on the lower extremity (more so than upper)
What are the 6 main groups of small vessel vasculitis?
Henoch-schonlein purpura, Acute hemorrhagic edema of infancy, urticarial vasculitis, erythema elevatum diutinum, granuloma faciale, secondary vasculitis (drug, infection, malignancy, autoimmune)
What are the main groups of mixed small and medium-sized vessel vasculitis?
Mixed cryoglobulinemia types II and III, ANCA-associated vasculitis: Microscopic polyangitis, Wegener’s granulomatosis, Chrug-Strauss syndrome
What are the hallmark dz’s of medium vessel vasculitis?
Polyarteritis nodosa and Kawasaki dz
What are the two main large-vessel vasculitides?
Temporal arteritis, Takayasu’s arteritis
What are the 5 main triggers of small vessel vasculitis?
infection (15-20%), inflammatory disorders (15-20%), Drug (10-15%), Neoplasm (<5%), other (thrombotic, embolic, cryoglobulinemia
Who gets cutaneous small vessel vasculitis most commonly?
Adults> children
What is the pathophysiology of cutaneous small vessel vasculitis?
Immune complex deposition in post-capillary venules which activates complement leading to a neutrophilic inflammatory response
- This causes vessel damage, hemorrhage, and tissue ischemia
- Fibrinoid necrosis of blood vessels arises via lysosomal enzymes (collagenases and elastases) and reactive oxidative species
This is why lower extremity is the most common, these deposits follow gravity, settle into lower extremity vessels
What are the most common infections associated with small-vessel vasculitis?
Bacterial: group A β-hemolytic Streptococci, Staphylococcus aureus, Chlamydia, Neisseria, Mycobacterium
Viral: hepatitis C > B ≫ A, HIV Fungal/yeast: Candida
What are the most common connective tissue diseases to cause small vessel vasculitis?
SLE, Sjogren’s, RA >>DM, scleroderma, polychondritis
IBD
Behcet’s
What are the most common drugs to cause small-vessel vasculitis?
Antibiotics: β-lactams (penicillin, cephalosporins), sulfonamides, minocycline, quinolones
Antiinflammatory: NSAIDS, COX-2 inhibitors
Most common neoplasms to be a/w small vessel vasculitis?
Hematologic malignancy (MM, monoclonal gammopathies) T-cell leukemia, MF, AML, CML, diffuse large cell leukemia, hairy cell leukemia
Solid-organ ca are much less commonly associated
What is the presentation of small vessel vasculitis?
Crops of partially blanchable, symmetric, palpable purpura on the lower extremities, dependent areas, and under tight clothing
Other manifestations: erythematous papules, urticaria,
vesicles, pustules, and livedo reticularis
Rarely happens on the face, palms, soles, or mucous membranes
What is the timing usually from exposure to onset of small vessel vasculitis lesions?
7-10 days
How long does small vessel vasculitis usually take to resolve?
3-4 weeks w/ some hyperpigmentation or atrophy
What kind of symptoms may be a/w small vessel vasculitis?
Skin: Asymptomatic, pruritus, or burning/pain
Systemic: fever, malaise, arthralgias, myalgias, and GI/GU sx’s.
If you note systemic sx’s need to consider a systemic vasculitis
In what percentage of patients is the small vessel vasculitis chronic and follows a relapsing course?
10%
What is the timing of the DIF and H&E biopsies to maximize diagnostic yield?
H&E: within 18-48 hrs
DIF: 8-24 hrs
What will be the DIF findings in small vessel vasculitis?
80% w/ perivascular C3 and IgM
What is the histology of small vessel vasculitis?
Perivascular neutrophilic infiltrate (w/ leukocytoclasis) centered around post-capillary venules w/ fibrinoid necrosis of vessel walls and endothelial swelling, and RBC extravasation
Concomitant involvement of the deeper larger vessels would suggests systemic vasculitis