A case of pancreatic pseudocysts accompanied by infection, pseudoaneurysm ruptures, and pseudocystocolonic fistulae.

Pancreatic pseudocysts (PPs) can be accompanied by infection, pseudoaneurysm ruptures, and fistulae to other organs, which can be fatal without appropriate treatment. Herein, we present the case of an 82-year-old man with PPs accompanied by infection, pseudoaneurysm rupture, and pseudocystocolonic fistula that were managed via multidisciplinary treatment. Computed tomography (CT) revealed two inflamed PPs, one each in the pancreatic head and tail. He was, therefore, diagnosed with infectious PPs. The pancreatic head PP shrunk on endoscopic nasopancreatic drainage (ENPD), but the pancreatic tail PP did not. Endoscopic ultrasound (EUS)-guided transluminal drainage was performed to treat the pancreatic tail PP; his symptoms improved. However, he vomited blood at 14 day post-drainage. Angiography revealed pseudoaneurysm rupture in a left gastric artery branch. After successful angioembolization, he developed hematochezia 2 days later. We suspected re-bleeding of the pseudoaneurysm. The bleeding stopped spontaneously, but CT and radiography revealed the presence of a pseudocystocolonic fistula. Careful follow-up was performed, and he has not had any symptoms at 9 month post-discharge. We managed PP-related complications via ENPD, EUS-guided transluminal drainage, angioembolization, and careful follow-up. Infection, pseudoaneurysm rupture, and pseudocystocolonic fistula are rare, but can occur simultaneously. Therefore, clinicians should consider these complications when treating patients with PPs.