A 50-year-old man consulted a local doctor because of epigastric pain and intermittent fever. Enhanced abdominal CT showed inflammatory changes of the pancreas, as well as portal vein obstruction. After hospitalization for conservative medical treatment, his symptoms improved. However, follow-up at the outpatient department showed an increase of chronic inflammatory parameters and CT revealed a new intraabdominal cystic lesion. Infection of the cyst was suspected. We performed percutaneous cyst puncture and drainage, but a new cyst and pancreatitis developed subsequently, and improvement was not achieved. The amylase level in the cyst fluid was high (69606 IU/l) . In addition, the portal system was visualized by cystography via the cyst drain tube, revealing a connection between the portal system and pancreatic duct. ERP was performed for evaluation of the pancreatic c duct, revealing that the pancreatic duct was obstructed in the head of the pancreas, but the guidewire could be inserted through the cyst intraportally beyond the duct and there was contrast enhancement of the portal vein. The portal vein contained organized thrombus. We placed a transpapillary drain tube in the cyst. Because a new cyst did not develop and there was no relapse of pancreatitis.
