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Systemic necrotizing vasculitis affecting medium-sized
arteries. The cutaneous form of PAN is associated with streptococcal
infection and seems to be a little more frequent in children.
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Periarteritis Nodosa; Kussmaul's Disease; Necrotizing Arteritis
Syndrome.
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First described in 1866 by Kussmaul and Meier. They identified a
condition that consisted of “focal, inflammatory, artery nodules”.
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Onset is generally between the ages of 40 and 50 but may also
occur at any age. The male-to-female ratio is 3:1. The cause and the true incidence
remain unknown.
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The cause remains unknown; however, the variety of
pathologic features suggests multiple pathogenic mechanisms. Spontaneously occurring
polyarteritis nodosa occurs in hyperimmunized human volunteers, in animals with
experimental serum sickness, and in patients developing hypersensitivity reactions.
Drugs (e.g., sulfonamides, penicillin, iodide, thiouracil, bismuth, thiazides,
guanethidine, methamphetamine), vaccines, bacterial infections (e.g., streptococcal,
staphylococcal), and viral infections (e.g., serum hepatitis, influenza, HIV) have been
associated with disease onset. Segmental, necrotizing inflammation of media and
adventitia characterizes the lesion. The pathologic process most commonly occurs at
points of vessel bifurcation, beginning in the media and extending into the intima and
adventitia of medium-sized arteries, often disrupting the internal elastic lamellae.
Early endothelial lesions contain polymorphonuclears and occasionally eosinophils; later
lymphocytes and plasma cells can be seen. Immunoglobulin, complement components, and
fibrinogen are deposited in the lesions, but their significance is unclear. Intimal
proliferation with secondary thrombosis and occlusion leads to organ and tissue
infarction. Weakening of the muscular vessel wall may cause small aneurysms and arterial
dissection. Healing can result in nodular fibrosis of the adventitia.
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Histologically, it is a necrotizing angiitis of small
and medium-size vessels whose manifestations are weight loss, fever,
asthenia, peripheral neuropathy, renal involvement, musculoskeletal and
cutaneous manifestations, hypertension, gastrointestinal (GI) tract involvement, cardiac
failure, and cerebral infarcts.
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Attacks of fever and cutaneous rash that
occasionally progress to gangrene and amputation of distal portions of toes
and fingers. The cutaneous PAN is usually restricted to the musculoskeletal
system and skin. Clinical findings can range from isolated cutaneous
findings to widespread multisystemic involvement (kidney, heart, liver). The
illness may present as ischemic colitis. Cardiac failure may be caused by
pericardial thickening or by histological changes of the myocardium and
atrioventricular valves, or by myocardial infarction. Cardiac involvement
may lead to cerebral infarction coming from the lesions of the endocardium
or the valves. Often associated with hypertension and eosinophilia. The
unique coexistence of polyarteritis nodosa, antiphospholipid antibodies
(aPL), and perinuclear antineutrophil cytoplasmic antibodies (p-ANCA) is
described. Disseminated intravascular coagulation may complicate the
illness. Treatment includes high-dose corticosteroids, often in combination
with cytotoxic or immunosuppressive agents such as cyclophosphamide or
azathioprine.
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In acute phase, check carefully the
cardiac and renal function. ...