MV usually presents with bleeding or ischemic symptoms. Upper and lower gastrointestinal bleeding is the most common presentation and is associated with mucosal lesions or rupture of small branch artery aneurysms. Mesenteric ischemia presents with symptoms that are indistinguishable from those of atherosclerotic or embolic origin. The classic symptoms include abdominal pain, postprandial pain, “food fear,” and weight loss. In patients with medium-size vessel vasculitis, such as polyarteritis nodosa (PAN), inflammation may lead to aneurysm formation and vessel rupture with either intra-abdominal or gastrointestinal ­hemorrhage. If the smaller arteries are involved, ulceration, perforation, and stricture formation can occur. In addition to bleeding and ischemic symptoms, patients often manifest other constitutional symptoms such as weight loss, malaise, fever, night sweats, arthralgias, myalgia, peripheral weakness, and headache.

Other less frequent manifestations include hepatitis, gastritis, esophagitis, pancreatitis, cholecystitis, and appendicitis [1, 3–10]. Nausea and vomiting are present in one-third of patients, and 27 % present with diarrhea.

Duplex ultrasound is used to screen test and evaluate patency of the visceral arteries and presence of hemodynamically significant stenoses or occlusions. The criteria to identify a high-grade stenosis include peak systolic velocity >275 cm/s for the superior mesenteric artery (SMA) and >200 cm/s for the celiac axis [11]. Selective mesenteric angiography remains the gold standard for diagnosis of mesenteric vasculitis. The classic finding includes long, tapered, smooth lesions without stigmata of atherosclerosis, such as calcifications or atheromatous plaque (Fig. 24.1). Multiple and small aneurysms are also frequently seem. Barium enema may show thumbprinting due to submucosal edema or hemorrhage. Computed tomography angiography (CTA) is an excellent imaging study to diagnose and plan the intervention. It allows greater spatial resolution and is useful to diagnose other potential causes of abdominal pain and weight loss (e.g., malignancy). Specific findings consistent with mesenteric vasculitis include vessel wall thickening, periarterial edema or stranding, and long, smooth lesions with or without concomitant aneurysms or pseudoaneurysms (Fig. 24.1). This study is useful to plan open surgical reconstruction, allowing selection of a diseased-free site for inflow and outflow of bypass procedures. In addition, evaluation of bowel wall thickening (e.g., the target sign), increased ­attenuation of mesenteric fat, pneumatosis intestinalis, or pneumoperitoneum is consistent with complicated acute ischemia, bowel gangrene, and perforation.

A variant of specific vasculitis can manifest with symptoms of mesenteric ischemia or bleeding complications (Table 24.2).