Hemosuccus Pancreaticus from Large Inferior Pancreaticoduodenal Artery Pseudoaneurysm Complicating Chronic Pancreatitis.

Hemosuccus pancreaticus is an uncommon cause of upper gastrointestinal bleeding characterized by hemorrhage entering the pancreatic duct and draining into the duodenum. Although pseudoaneurysms may arise from several peripancreatic vessels in the setting of chronic pancreatitis, involvement of the inferior pancreaticoduodenal artery (IPDA) is particularly uncommon and carries a high risk of rupture. A man in his late 30s with a known history of chronic calcific pancreatitis presented with melena, severe anemia, and hemodynamic instability. Side-viewing duodenoscopy revealed intermittent bleeding from the ampulla of Vater, raising suspicion for hemosuccus pancreaticus. Computed tomography angiography identified a 6.4 cm IPDA pseudoaneurysm causing multi-organ compression. Successful endovascular coil embolization achieved complete occlusion of the pseudoaneurysm. This case demonstrates successful minimally invasive management and diagnostic challenges of a life-threatening vascular complication of chronic pancreatitis. High clinical suspicion, early targeted imaging, and prompt intervention are essential for preventing catastrophic hemorrhage.