(IV) Vasculitides Flashcards
- What is the definition of vasculitis? What are the vascular consequences?
Inflammation and necrosis of a blood vessel with subsequent impairment of blood flow. Vessel
wall destruction ->perforation and hemorrhage into adjacent tissues. Thrombosis -> impairment of blood flow -> ischemia/infarction of dependent tissues. Complx: accelerated 2/2 ATH of the involved vessel, which contributes to
morbidity and mortality.
Histologic features of vasculitis?
Infiltration of the vessel wall by neutrophils, mononuclear cells, and/or giant cells
• Fibrinoid necrosis (panmural destruction of the vessel wall)
• Leukocytoclasis (dissolution of leukocytes, yielding “nuclear dust”)
Perivascular infiltration is a nonspecific histologic finding & not diagnostic of vasculitis,
immune mechanism does vasculitis occur?
Cell-mediated vasculitis:
GCA
Takayasu arteritis,
Primary CNS vasculitis
IC mediated vasculitis: PAN HSP cryoglobulinemic vasculitis, cut leukocytoclastic angiitis.
ANCA-assoc vasculitides: (+/- cellular & humoral) GPA MPA EGPA
Cell-mediated vasculitis
Cell-mediated vasculitis:
GCA
Takayasu arteritis,
Primary CNS vasculitis
IC med vasculitis
IC mediated vasculitis: PAN HSP Cryoglobulinemic vasculitis, Cut leukocytoclastic angiitis.
AAV
ANCA-assoc vasculitides: (+/- cellular & humoral) GPA MPA EGPA
Abbrev?
GCA
PAN
HSP
GPA
MPA
EGPA
GCA
PAN
HSP
GPA
MPA
EGPA
Microscopic polyangiitis (MPA) Eosinophilic granulomatosis with polyangiitis (EGPA) (Churg-Strauss)
Chapel Hill
Large Med Small Variable Single organ Assoc with sys dz Assoc with probably cause
Large vessel
Takayasu & GCA
Medium vessel
PAN & Kawasaki
Small vessel
- IC-mediated*
- Anti-GBM
- Cryoglobulinemic vasculitis
- IgA vasculitis(HSP
- Hypocomplementemic urticarial (HUVS, anti-Clq vasculitis)
- ANCA(pauci-immune)*
- GPA
- MPA
- EPA
Variable vessel
Bechet & Cogan
Single Organ vasc
Cutaneous leukocytoclastic vasculitis Cutaneous arteritis Primary CNS Isolated aortitis Others
vasc with sys dz
SLE
RA
Sarcoid & others
Vasc with probable eitology
Hep C cryoglobulinemic vasculitis Hep B vasculitis Syphilis vasculitis Drug-assoc IC vasculitis (HSR) Drug-assoc ANCA vasculitis Cancer vasculitis Others
Presentations
Large-:
limb claudication,
bruits, asymmetric BP, absence of pulses
• Medium:-: cutaneous nodules, ulcers, livedo reticularis, digital gangrene, mononeuritis multiplex, renovascular HTN
• Small: palpable purpura, urticaria, glomerulonephritis, alveolar hemorrhage, scleritis
PEARL
MCC Presentation for vasc
PEARL:
Headache or visual loss in the elderly->GCA
asymmetric pulses + bruits + <30 y/o ->Takayasu
mononeuritis multiplex->PAN
rapidly prog pulm–renal syn->AAV
palpable purpura->IC mediated vasculitis
When to suspect vasc mimics??
Vasculitis mimics should be suspected when there is:
1. A new heart murmur (subacute bacterial endocarditis, SBE)
- Necrosis of lower-extremity digits (cholesterol emboli)
- Splinter hemorrhages (SBE)
- Prominent liver dysfunction (hepatitis C)
- Drug abuse (human immunodeficiency virus, HIV; hepatitis B/C; cocaine, etc.)
- Prior diagnosis of neoplastic disease
- Unusually high fever (SBE)
- History of high-risk sexual activity (HIV)
What disorders can mimic Large arteries?
Fibromuscular dysplasia, radiation fibrosis, neurofibromatosis type I, congenital coarctation of
aorta, genetic diseases (Marfan syndrome, Loeys–Dietz syndrome), syphilitic aortitis, IgG4 disease
What disorders can mimic Medium arteries ?
Cholesterol emboli syndrome, atrial myxoma, fibromuscular dysplasia, lymphomatoid granulomatosis,
angioblastic T-cell lymphoma, thromboembolic disease, ergotism, type IV Ehlers–Danlos syndrome,
segmental arterial mediolysis, Grange syndrome, pseudoxanthoma elasticum
What disorders can mimic Cerebral arteries ?
Reversible cerebral vasoconstrictive syndrome, reversible posterior encephalopathy syndrome,
cerebral amyloid angioapthy, CADASIL syndrome, Susac syndrome, progressive multifocal leukoencephalopathy,
Moyamoya disease, intravascular lymphoma, infections
What disorders can mimic Small arteries ?
Infectious endocarditis, mycotic aneurysm with emboli, cholesterol microemboli syndrome, antiphospholipid antibody syndrome, sepsis (gonococcal, meningococcal), ecthyma gangrenosum (Pseudomonas), thrombotic thrombocytopenia purpura, cocaine, amphetamines, minocycline, hydralazine, HIV, hepatitis C, amyloidosis, systemic rheumatic diseases (systemic lupus erythematosus, SLE; Sjögren’s syndrome), bacteremias (SBE, Rickettsia), other systemic viral infections, common variable immunodeficiency, calciphylaxis, livedoid vasculopathy (atrophie blanche), malignant atrophic papulosis (Degos disease)
To rule out vasculitis mimics:,
consider blood cultures, viral hepatitis studies, HIV testing, urinary toxicology
screening, echocardiography, antinuclear antibody (ANA), rheumatoid factor (RF), antiphospholipid antibodies,
and/or angiography/magnetic resonance angiography, depending on the clinical situation
Jaw claudication, visual loss, palpable, thickened,
tender temporal artery, or
Diminished temporal artery pulsation
Giant cell arteritis (GCA)
Absent radial pulses, difficulty obtaining a blood pressure
in one arm
Takayasu arteritis or large artery involvement in GCA
Sinus involvement, otitis media, scleritis
GPA (Wegener) or EGPA (Churg–Strauss syndrome)
Hypertension, renal vascular involvement
Polyarteritis nodosa or Takayasu arteritis
Asthma
EGPA (Churg–Strauss syndrome)
Pulmonary–renal syndromes (hemoptysis and glomerulonephritis)
GPA (Wegener) and microscopic polyangiitis
Testicular tenderness
Polyarteritis nodosa
subcutaneous nodules, “punched-out” skin ulcers, livedo reticularis, digital
gangrene
Medium-vessel vasculitis:
palpable purpura, splinter hemorrhages, hemorrhagic macules, vesiculobullous
lesions,
and urticaria lasting >24 hours
Small-vessel vasculitis
Primary systemic vasculitis never causes pancytopenia (must rule out SLE, B cell lymphoma, myeloma,
leukemia)
Westergren ESR and CRP. ESR >100 mm/h and CRP >10 mg/dL in the absence of bacterial infection and
widespread cancer should suggest vasculitis.
c-ANCA
if against serine proteinase 3, usually GPA; sometimes MPA
highly specific for GPA with widespread systemic involvement
>90%
p-ANCA
if against myeloperoxidase, consider MPA and EGPA; sometimes GPA.
If the p-ANCA is not against myeloperoxidase, inflammatory diseases
other than vasculitis should be considered (inflammatory bowel disease, infections). In some patients, ANCAs
may have predictive value for relapses and ongoing disease activity. ANCAs may be pathogenic as part of
several simultaneous or sequential events.
When are hepatitis serologies helpful when vasculitis is suspected?
The presence of hepatitis B surface antigen may be found in some patients (10% to 25%, depending on risk
factors) with PAN. Hepatitis C antibodies are often found in patients with essential mixed cryoglobulinemic
vasculitis and rarely in PAN.
What is the role of tissue biopsy in the diagnosis of vasculitis and in what type of vasculitis might
tissue biopsy be helpful?
Tissue biopsy is unquestionably the procedure of choice in the diagnosis of vasculitis. Some frequently
approached biopsy sites are as follows:
• Common sites: Skin, sural nerve (PAN, EGPA; only biopsy if abnormal electromyogram [EMG]/nerve
conduction velocity [NCV]), temporal artery (GCA), muscle (PAN), kidney (GPA, MPA; rare to see
vasculitis, usually see focal necrotizing glomerulonephritis with or without crescents), lung (GPA, MPA)
• Less common sites: Testicle (PAN), rectum/gut, liver, heart, brain (primary CNS vasculitis), sinus (GPA)
- If tissue biopsy is not feasible, what alternative procedures can yield a diagnosis?
Angiography at the following sites may be helpful for diagnosis of certain types of vasculitis:
• Abdomen (celiac trunk, superior mesenteric, and renal arteries) for diagnosis of PAN
• Aortic arch for diagnosis of Takayasu arteritis and GCA with large-vessel involvement.
• Extremities for diagnosis of Buerger disease
• Cerebral sites for diagnosis of primary CNS vasculitis
List two characteristic (but not diagnostic) angiographic features of vasculitis
Irregular tapering and narrowing & Aneurysms (“beading”)
noninvasive tests can be used to determine vessel involvement in patients with vasculitis?
Doppler ultrasound of temporal arteries can localize the area of narrowing in GCA and help determine
biopsy sites.
• Magnetic resonance angiography of the aorta can reveal aortic wall thickening (enhancement with
gadolinium indicates inflammation) and areas of stenosis in patients with Takayasu arteritis or GCA with
large-artery involvement.
• Positron emission tomography can reveal enhancement of the aortic and subclavian vessel wall if active
inflammation occurs in patients with Takayasu arteritis and GCA
