Vasculitis

VASCULITIS

DR IMRANA TANVIR

Vasculitis Vasculitis is a general term for vessel wall

inflammation. Vessels of any type in virtually any organ

can be affected,but most vasculitides affect small vessels ranging in size from arterioles to capillaries to venules.

The two common pathogenic mechanisms of vasculitis are immune-mediated inflammation and direct invasion of vascular walls by infectious pathogens.

Vasculitis: Definition Pathologist Inflammatory destruction of

blood vessels Infiltration of vessel wall with

inflammatory cells Leukocytoclasis Elastic membrane disruption Fibrinoid necrosis of the

vessel wall Ischemia, occlusion,

thrombosis Aneurysm formation Rupture, hemorrhage

Rheumatologist A clinicopathologic process

characterized by inflammatory destruction of blood vessels that results in occlusion or destruction of the vessel and ischemia of the tissues supplied by that vessel.

“Systemic vasculitides”

Vacuities: Classification Large-vessel vasculitis Giant cell arteritis, Takayasu’s arteritis Behcet’s disease, Cogan’s syndrome Medium-vessel vasculitis Polyarteritis nodosa Buerger’s disease, Central nervous system vasculitis,

Kawasaki’s disease, Rheumatoid vasculitis Small-vessel vasculitis Wegener’s, microscopic polyangiitis, Churg-Strauss Cryoglobulinemic vasculitis, Henoch-Schönlein

purpura,

Vasculitis: Classification Large-vessel vasculitisAorta and the great vessels (subclavian, carotid)Claudication, blindness, stroke Medium-vessel vasculitisArteries with muscular wallMononeuritis multiplex (wrist/foot drop),

mesenteric ischemia, cutaneous ulcers Small-vessel vasculitisCapillaries, arterioles, venulesPalpable purpura, glomerulonephritis, pulmonary

hemorrhage

Giant Cell (Temporal) Arteritis It is a chronic inflammatory disorder of

large to small-sized arteries that principally affects arteries in the head—especially the temporal arteries—but also the vertebral and ophthalmic arteries. Ophthalmic arterial involvement can lead abruptly to permanent blindness; consequently, giant cell arteritis is a medical emergency requiring prompt recognition and treatment.

T-cell–mediated immune response against one of handful of vessel wall antigens that drives

subsequent proinflammatory cytokine production (particularlyTNF).

Anti-endothelial cell and anti-smooth musclecell antibodies can also be demonstrated in

roughly two thirds of patients, although it is unclear whether these are causal or a consequence of other immune injury.

A cellular immune etiology is supported by the characteristic granulomatous response, a correlation with certain MHC class II haplotypes, and a prompt therapeutic response to steroids.

MORPHOLOGY Intimal thickening (with occasional thromboses)

that reduces the luminal diameter. Classic lesions exhibit medial granulomatous

inflammation centered on the internal elastic lamina that produce elastic lamina fragmentation;

There is an infiltrate of T cells (CD4+ CD8+) and macrophages. Although multinucleated giant cells are seen in approximately 75% of adequately biopsied specimens

Granulomas and giant cells can be rare or absent.

Inflammatory lesions are only focally distributed along the vessel and long segments of relatively normal artery may be

interposed. The healed stage is marked by medial

attenuation and scarring with intimal thickening, typically with residual elastic tissue fragmentation and adventitial fibrosis.

Clinical Features. Rare before age 50 Symptoms may be only vague and

constitutional—fever,fatigue, weight loss—or there may be facial pain or headache, most intense along the course of the superficial temporal artery, which can be painful to palpation.

Ocular symptoms (associated with involvement of the ophthalmic artery) appear abruptly in about 50% of patients;

ELASTIN STAIN

Doctor, Doctor, my teenage son coughed up blood

15 y/o male with hx of chronic sinusitis and congestion, here with complaints of hemoptysis and dyspnea but stable now.

Granulomatosis with Polyangiitis Previously called Wegeners granulomatosis Differential diagnosis

sarcoid TB Churg Strauss

Epidemiology of WGN mostly kidney and lung with granuolomas adults (4th and 5th decades) >>>kids caucasians >>>noncaucasian initially with respiratory symptoms and then renal

insufficiency

Granulomatosis with Polyangiitis Diagnosis: Clinical findings of sinusitis and pulm

finding, order high resolution CT. Check ANCA: (90% of WGN have the marker) with 70% sensitivity

Bx: lung: granulomas with geographic patterns of

central necrosis and accompanying vasculitis renal: 10% with granulomas, segmental necrotizing

GN RX: rapid therapy needed

Steroids cyclophosphamide

Showing features characteristic of granulomatosis with polyangiitis - a vasculitis and granulomas with multi-nucleated giant cells.

Churg-Strauss Syndrome Churg-Strauss syndrome is a small-vessel

necrotizing vasculitis classically associated with asthma, allergic rhinitis,lung infiltrates, peripheral hypereosinophilia, and extravascular necrotizing granulomata.

Multisystem diseases with cutaneous involvement (palpable purpura)gastrointestinal tract bleeding, and renal disease (primarily as focal and segmental glomerulosclerosis). Myocardial involvement may give rise to cardiomyopathy

Lung and extrapulmonary sites (skin, heart, nervous system, GI) have prominent eosinophilic infiltrate, granulomatous reaction around necrotic foci with radially arranged histiocytes and pallisading giant cells near small arteries or arterioles, eosinophilic vasculitis

● May have fibrin-rich edema, lymphocytes, sarcoid-like granulomas, focal fibrosis and eosinophilic microabscesses

Behçet Disease Behçet disease is a small- to medium-

vessel neutrophilic vasculitis that classically presents as a clinical triad of recurrent oral aphthous ulcers, genital ulcers, and uveitis.

Thromboangiitis obliterans Buerger’s Disease Thromboangiitis obliterans or Buerger's disease is

a segmental occlusive inflammatory condition of arteries and veins, characterized by thrombosis and recanalization of the affected vessels.

It is a non-atherosclerotic inflammatory disease affecting small and medium sized arteries and veins of upper and lower extremities.

The etiology of thromboangiitis obliterans is unknown, but use or exposure to tobacco is central to the initiation and progression of the disease.

MORPHOLOGY focal acute and chronic vasculitis of

small- and medium-sized arteries,predominantly of the extremities.

Acute and chronic inflammation, accompanied by luminal thrombosis. The thrombus can contain small microabscesses composed of neutrophils surrounded by granulomatous inflammation

Clinical Features Early manifestations include cold induced Raynaud

phenomenon (see later), leg pain induced by exercise that is relieved on rest (intermittent claudication), instep foot pain induced by exercise (instep claudication), and a superficial nodular phlebitis.

Chronic extremity ulcerations develop, progressing over time to frank gangrene. Smoking abstinence in the early stages of the disease can often ameliorate further attacks; however, once established, the vascular lesions typically do not respond to smoking abstinence.

Infectious Vasculitis Arteritis can be caused by the direct

invasion of infectious agents, usually bacteria (Pseudomonas being the classic example) or fungi, in particular Aspergillus and Mucor

species. Vascular invasion can be part of a

localized tissue infection (e.g., bacterial pneumonia or adjacent to abscesses).

Vascular infections can weaken arterial walls and culminate in mycotic aneurysms (see earlier), or can induce thrombosis and infarction.

References: Nelson’s Pediatrics Harrison’s Internal Medicine Google search for pictures AAP Board PREP CMDT 2004