RESUMO
The pancreaticoduodenal arteries are rare sites for true aneurysm formation, but these may develop in association with occlusion of the coeliac circulation, degenerative conditions or inflammatory vascular disorders. These have a high risk of rupture regardless of size or other factors. One identified cause is polyarteritis nodosa (PAN), which is an autoimmune necrotising vascular condition that affects small-sized and medium-sized arteries. We report a case of a 40-year-old man with massive gastrointestinal tract bleeding from a ruptured pancreaticoduodenal artery aneurysm secondary to PAN. This was managed with emergent open aneurysm ligation followed by high-dose corticosteroids and cyclophosphamide pulse therapy. Only three other cases of PAN-associated pancreaticoduodenal artery aneurysms have been reported in the literature.