Pancreatic mass as an initial manifestation of polyarteritis nodosa: A case report and review of the literature

Figure 1 Preoperative images. A: An ultrasonogram showing a slightly ill-defined hypoechoic mass at the pancreatic head; B-E Abdominal CT scans: The pancreatic mass is slightly hypodense on simple CT; C: Enhanced CT shows a non-enhancing mass (arrow) located adjacent to the bile duct (arrowhead) at the arterial phase. Note that the walls of the gallbladder (asterisk) and bile duct are thickened; D and E; The mass has sporadic enhancement at the later phase; F: A Cholangiogram showing a tapered distal biliary stricture consistent with extrinsic compression by the pancreatic mass. CT: Computed tomography.

Figure 2 Histological findings of the pancreas, gallbladder and kidney. A: Pancreatic fibrotic changes adjacent to the bile duct (asterisk) are evident. An obliterated medium-sized artery (arrow) is accompanied by cellular infiltration and destruction of the wall. The bile duct mucosa is intact (hematoxylin-eosin stain; original magnification, × 40); B: The affected small-sized artery in the pancreatic fibrosis is characterized by necrotizing arteritis with subintimal fibrinoid necrosis and inflammatory cell infiltration (hematoxylin-eosin stain; original magnification, × 100); C: The arteries of the gallbladder are also involved: the mucosa is preserved (hematoxylin-eosin stain; original magnification, × 40); D and E: Renal biopsy showed segmental sclerosis and collapse with a fibrocellular crescent (D: Periodic acid-Shiff’s stain, original magnification, × 200) and vasculitis of a small-sized artery (E: Periodic acid-Shiff’s stain, original magnification, × 100 ).