A case of polyarteritis nodosa with lesions of the superior mesenteric artery illustrating the diagnostic usefulness of three-dimensional computed tomographic angiography.

A 40-year-old Japanese man who developed upper abdominal pain, weight loss, and hypertension was diagnosed as suffering with polyarteritis nodosa (PAN) with lesions of the superior mesenteric artery (SMA). Three-dimensional computed tomographic angiography (3D-CTA) and conventional angiography revealed smooth segmental luminal narrowing of the branches of the SMA. In addition, an enhanced abdominal CT scan demonstrated diffuse thickening of the wall of the affected SMA. Treatment with high-dose corticosteroids resulted in immediate improvement of the abdominal manifestations and normalized the serum C-reactive protein levels. Furthermore, the subsequent enhanced CT and 3D-CTA revealed improvement of the wall thickening and luminal narrowing of the SMA and its branches during the treatment period. In addition to possessing the diagnostic usefulness of conventional angiography, 3D-CTA is also less invasive and facilitates the prompt and accurate diagnosis of PAN. Furthermore, thickening of the wall of medium-sized arteries evidenced by enhanced CT scan may also support a diagnosis of PAN.