Abdominal polyarteritis nodosa: angiographic features

Polyarteritis nodosa (PAN) is a systemic vasculitis of small and medium size arteries. The purpose of this study is to evaluate imaging findings, especially angiographic features, of 17 patients with abdominal involvement from polyarteritis nodosa. We reviewed the medical records and imaging findings of 17 patients with PAN involving the abdomen. All patients underwent digital subtraction angiography of the renal or visceral arteries completed by a post-angiographic KUB. Abdominal CT scan was available in three patients. All patients underwent muscle biopsy. A surgical biopsy of the gallbladder was obtained in one patient. Multiple small aneurysms involving small and medium sized arteries were detected at angiography in 12 patients. CT showed a renal subcapsular hematoma in two patients and acute pancreatitis in one patient. Involvement of gastrointestinal and renal arteries is frequent in polyarteritis nodosa. The diagnosis of PAN should be considered when multiple small-sized aneurysms are present at angiography even if biopsy is negative.