Polyarteritis Nodosa (PAN)
Epidemiology and
Etiology:
Common sites:
- Small or
medium-sized muscular arteries
- Not arterioles,
capillaries, or venules
- Predilection
for
- Kidney
- Heart
- Liver
- GI
- Other viscera
- NOT lung
Gross features:
- Ulcerations
- Infarcts
- Ischemic
atrophy
-
- Aneurysmal dilation of vessels
maybe
- Rupture
of vessels maybe
Histologic
features:
- Segmental
(involving only a portion of vessels circumference)
- Transmural necrotizing
inflammation
- Neutrophils
- Eosinophils
- Mononuclear
cells
- Fibrinoid necrosis
- Thrombosis
in lumen maybe
- Fibrous
thickening of vessel walls
- Characteristic
varying age of lesions from acute to fibrotic in the same biopsy
- Small vessel
involvement is absent
- No glomerulonephritis
Immunophenotype:
Marker:
|
Sensitivity:
|
Specificity:
|
|
|
|
Molecular features:
Other features:
- Frequently
remittent and episodic course
- Renal involvement
often prominent and is a major cause of death
- Serum Hep B Ag (30%)
- Remission
or cure with corticosteroids and cyclophosphamide
(90%)
References:
·
Kumar V, Fausto N, Abbas
A. Robbins & Cotran Pathologic Basis of Disease,
Seventh Edition. 7th ed. Saunders; 2004.