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In medicine, vasculitis (plural: vasculitides) is a group of diseases featuring inflammation of the wall of blood vessels due to leukocyte migration and resultant damage. While most vasculitides are rare, they generally affect several organ systems and can cause severe disability.
Large vessel vasculitis Takayasu arteritis. Primarily affects the aorta and its main branches. At least 3 out of 6 criteria yields sensitivity and specificity of 90.5 and 97.8%: Giant cell (temporal) arteritis. Chronic vasculitis of both large and medium vessels, primarily affecting cranial branches of the arteries arising from the aortic arch. At least 3 out of 5 criteria yields sensitivity and specificity of 95 and 91%: Medium vessel vasculitis Polyarteritis nodosa. Systemic necrotizing vasculitis and aneurysm formation affecting both medium and small arteries. If only small vessels are affected, it is called microscopic polyangiitis, although it is more associated with Wegener's granulomatosis than to classic PAN. At least 3 out of 10 criteria yields sensitivity and specificity of 82 and 87%: Wegener's granulomatosis. Systemic vasculitis of medium and small arteries, including venules and arterioles. Produces granulomatous inflammation of the respiratory tracts and necrotizing, pauci-immune glomerulonephritis. Most common cause of saddle nose deformity in USA (nose flattened due to destruction of nasal septum by granulomatous inflammation). Almost all patients with WG has c-ANCA, but not vice versa. Current treatment of choice is cyclophosphamide. At least 2 out of 4 criteria yields sensitivity and specificity of 88 and 92%. Kawasaki disease. Usually in children, it affects large, medium, and small vessels, prominently the coronary arteries. Associated with a mucocutaneous lymph node syndrome. Diagnosis requires fever lasting five days or more with at least 4 out of 5 criteria: Isolated CNS vasculitis. Affects medium and small arteries over a diffuse CNS area, without symptomatic extracranial vessel involvement. Patients have CNS symptoms as well as cerebral vasculitis by angiography and leptomeningeal biopsy. Small vessel vasculitis Churg-Strauss arteritis. Affects medium and small vessels with vascular and extravascular granulomatosis. Classically involves arteries of lungs and skin, but may be generalized. At least 4 criteria yields sensitivity and specificity of 85 and 99.7%. Microscopic polyarteritis/polyangiitis. Affects capillaries, venules, or arterioles. Thought to be part of a group that includes Wegeners since both are associated with ANCA and similar extrapulmonary manifestations. Patients do not usually have symptomatic or histologic respiratory involvement. Hypersensitivity vasculitis. Usually due to a hypersensitivity reaction to a known drug. There is presence of skin vaculitis with palpable petechiae or purpura. Biopsy of these lesions reveal inflammation of the small vessels, termed leukocytoclastic vasculitis, which is most prominent in postcapillary venules. At least 3 out of 5 criteria yields sensitivity and specificity of 71 and 84%: Henoch-Schonlein purpura. Systemic vasculitis due to tissue deposition of IgA-containing immune complexes. Biopsy of lesions shows inflammation of small vessels. It is considered a form of hypersensitivity vasculitis but is distinguished by prominent deposits of IgA. This is the most common vasculitis in children. Presence of 3 or more criteria yielded sensitivity of 87% while less than 2 criteria yielded hypersensitivity vasculitis in 74%: Essential cryoglobulinemic vasculitis. Most often due to hepatitic C infection, immune complexes of cryoglobulins --- proteins that consists of immunoglobulins and complement and precipitate in the cold while dissolving upon rewarming --- are deposited in walls of capillaries, venules, or arterioles. Therefore, complement will be low with histology showing vessel inflammation with immune deposits. Vasculitis secondary to connective tissue disorders. Usually secondary to SLE, RA, relapsing polychondritis, Behce'ts disease, and other connective tissue disorders. Vasculitis secondary to viral infection. Usually due to hepatitis B and C, HIV, cytomegalovirus, Epstein-Barr virus, and Parvo B19 virus. Symptoms and signs Patients usually present with systemic symptoms with single or multiorgan dysfunction. Common (and nonspecific) complaints include fatigue, weakness, fever, arthralgias, abdominal pain, hypertension, renal insufficiency, and neurologic dysfunction. The following symptoms should raise a strong suspicion of a vasculitis: Diagnosis A detailed history is important to elicit any recent medications, any risk of hepatitis infection, or any recent diagnosis with a connective tissue disorder such as SLE. A thorough physical exam is needed as usual. Treatment Treatment is targeted to the underlying cause. However, most vasculitis in general are treated with steroids (e.g. methylprednisolone) because the underlying cause of the vasculitis is due to hyperactive immunological damage. Immunosuppressants such as cyclophosphamide and azathioprine may also be given. Source | ||||||||
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