Isolated intestinal polyarteritis nodosa in an elderly patient.

Polyarteritis nodosa (PAN) is a necrotising systemic vasculitis involving medium-sized and small-sized vessels. PAN limited to a single organ is rare, particularly in the elderly population. Herein, we present a 73-year-old-woman who developed severe abdominal pain. Mesenteric angiography showed multifocal areas of segmental dilation and narrowing of the superior mesenteric, ileocolic and right colonic arteries. Exploratory laparotomy revealed multiple areas of necrosis of the jejunum for which resection was performed. Histopathological exam disclosed mesenteric vasculitis with fibrinoid necrosis of the arterial wall with leucocytic infiltrates and haemorrhages consistent with PAN. She was started on high-dose corticosteroids with an initial good response. However, 6 months later, she developed intestinal pseudo-obstruction for which oral cyclophosphamide was started. After 5 months of cyclophosphamide therapy, she remained stable without further relapses. Our case suggests that PAN should be considered in elderly patients presenting with abdominal pain even in the absence of systemic involvement.